Merge fix/830

Bumps the actions group with 1 update in the / directory: [actions/checkout](https://github.com/actions/checkout).


Updates `actions/checkout` from 4 to 7
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v4...v7)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: actions
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/dependabot.yml

@@ -0,0 +1,32 @@
+version: 2
+updates:
+  # Maintain Rust / Cargo dependencies
+  - package-ecosystem: "cargo"
+    directories:
+      - "/"
+      - "/plugins"
+    schedule:
+      interval: "daily"
+      time: "06:00"
+      timezone: "America/New_York"
+    # Consolidate updates into a single PR rather than one PR per crate
+    groups:
+      cargo-dependencies:
+        patterns:
+          - "*"
+    commit-message:
+      prefix: "chore(deps)"
+
+  # Maintain GitHub Actions workflows
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "daily"
+      time: "06:00"
+      timezone: "America/New_York"
+    groups:
+      actions:
+        patterns:
+          - "*"
+    commit-message:
+      prefix: "ci(deps)"

.github/workflows/ci.yml

@@ -33,7 +33,7 @@ jobs:
     name: test (ubuntu-latest)
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
 
       - name: Install Linux system dependencies (egui/winit/rfd)
         run: |
@@ -74,7 +74,7 @@ jobs:
     name: wasm32 check
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@stable
         with:
           targets: wasm32-unknown-unknown

.github/workflows/nix.yml

@@ -18,16 +18,6 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
-  eval:
-    runs-on: ubuntu-latest
-    timeout-minutes: 15
-    steps:
-      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
-      - uses: cachix/install-nix-action@13d8dd58da0234aa297dedd986986ccb8e7f3e24 # v31.11.1
-      - name: nix flake check --no-build
-        run: |
-          if [ -f flake.nix ]; then
-            nix flake check --no-build --all-systems
-          else
-            echo "No flake.nix present in this repository; skipping check."
-          fi
+  nix:
+    # Intentionally tracked at @main (not SHA-pinned) so org-wide CI improvements, security fixes, and build optimizations propagate without PR churn across all craftapp repos.
+    uses: storytold/craft-common-actions/.github/workflows/nix.yml@main

Cargo.lock

@@ -856,6 +856,11 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "craft-docpath"
+version = "0.1.0"
+source = "git+https://github.com/storytold/craft-libs?rev=82a24b006eefa036b43c09a67fb9a3fbd17ffe63#82a24b006eefa036b43c09a67fb9a3fbd17ffe63"
+
 [[package]]
 name = "crc32fast"
 version = "1.5.2"
@@ -1408,7 +1413,7 @@ checksum = "b97b65636e5b9ef369943878ac74335ba1c55c1cb6adbf1e2c293c624248d693"
 
 [[package]]
 name = "figcraft"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "arboard",
  "eframe",
@@ -1422,17 +1427,20 @@ dependencies = [
  "fmv-macos-events",
  "image",
  "log",
+ "raw-window-handle",
  "rfd",
  "serde_json",
  "wat",
+ "wayland-client",
  "webbrowser",
  "windows",
+ "winit",
  "winresource",
 ]
 
 [[package]]
 name = "figcraft-cli"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "figcraft-doc",
  "figcraft-engine",
@@ -1446,7 +1454,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-collab"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "base64 0.22.1",
  "figcraft-color",
@@ -1461,7 +1469,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-collab-net"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "base64 0.22.1",
  "figcraft-collab",
@@ -1484,7 +1492,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-color"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "kurbo",
  "serde",
@@ -1493,7 +1501,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-doc"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "figcraft-color",
  "figcraft-geom",
@@ -1505,9 +1513,10 @@ dependencies = [
 
 [[package]]
 name = "figcraft-engine"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "base64 0.22.1",
+ "craft-docpath",
  "figcraft-collab",
  "figcraft-color",
  "figcraft-doc",
@@ -1532,7 +1541,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-format"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "figcraft-doc",
  "figcraft-pathops",
@@ -1547,7 +1556,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-geom"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "kurbo",
  "serde",
@@ -1555,7 +1564,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-layout"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "figcraft-doc",
  "figcraft-geom",
@@ -1563,7 +1572,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-mcp"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "base64 0.22.1",
  "figcraft-collab-net",
@@ -1579,7 +1588,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-pathops"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "figcraft-doc",
  "figcraft-geom",
@@ -1588,7 +1597,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-pdf"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "figcraft-color",
  "figcraft-doc",
@@ -1600,12 +1609,12 @@ dependencies = [
  "krilla",
  "log",
  "thiserror 2.0.21",
- "tiny-skia",
+ "tiny-skia 0.12.0",
 ]
 
 [[package]]
 name = "figcraft-plugin"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "figcraft-color",
  "serde",
@@ -1618,7 +1627,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-render"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "crc32fast",
  "figcraft-color",
@@ -1631,12 +1640,12 @@ dependencies = [
  "moxcms",
  "png",
  "rayon",
- "tiny-skia",
+ "tiny-skia 0.12.0",
 ]
 
 [[package]]
 name = "figcraft-server"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "crc32fast",
  "ctrlc",
@@ -1660,7 +1669,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-svg"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "base64 0.22.1",
  "figcraft-color",
@@ -1676,7 +1685,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-text"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "figcraft-doc",
  "figcraft-geom",
@@ -1690,7 +1699,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-ui-egui"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "base64 0.22.1",
  "egui",
@@ -1715,7 +1724,7 @@ dependencies = [
 
 [[package]]
 name = "figcraft-web"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "eframe",
  "egui",
@@ -2570,7 +2579,7 @@ dependencies = [
  "skrifa 0.42.1",
  "smallvec",
  "subsetter",
- "tiny-skia-path",
+ "tiny-skia-path 0.12.0",
  "xmp-writer",
  "yoke",
  "zune-jpeg",
@@ -4018,6 +4027,17 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
+[[package]]
+name = "sctk-adwaita"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6277f0217056f77f1d8f49f2950ac6c278c0d607c45f5ee99328d792ede24ec"
+dependencies = [
+ "log",
+ "smithay-client-toolkit 0.19.2",
+ "tiny-skia 0.11.4",
+]
+
 [[package]]
 name = "self_cell"
 version = "1.3.0"
@@ -4477,6 +4497,20 @@ dependencies = [
  "zune-jpeg",
 ]
 
+[[package]]
+name = "tiny-skia"
+version = "0.11.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "83d13394d44dae3207b52a326c0c85a8bf87f1541f23b0d143811088497b09ab"
+dependencies = [
+ "arrayref",
+ "arrayvec",
+ "bytemuck",
+ "cfg-if",
+ "log",
+ "tiny-skia-path 0.11.4",
+]
+
 [[package]]
 name = "tiny-skia"
 version = "0.12.0"
@@ -4489,7 +4523,18 @@ dependencies = [
  "cfg-if",
  "log",
  "png",
- "tiny-skia-path",
+ "tiny-skia-path 0.12.0",
+]
+
+[[package]]
+name = "tiny-skia-path"
+version = "0.11.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c9e7fc0c2e86a30b117d0462aa261b72b7a99b7ebd7deb3a14ceda95c5bdc93"
+dependencies = [
+ "arrayref",
+ "bytemuck",
+ "strict-num",
 ]
 
 [[package]]
@@ -4778,7 +4823,7 @@ dependencies = [
  "skrifa 0.44.0",
  "strict-num",
  "svgtypes",
- "tiny-skia-path",
+ "tiny-skia-path 0.12.0",
  "unicode-bidi",
  "unicode-script",
  "unicode-vo",
@@ -5731,6 +5776,7 @@ dependencies = [
  "raw-window-handle",
  "redox_syscall 0.4.1",
  "rustix 0.38.44",
+ "sctk-adwaita",
  "smithay-client-toolkit 0.19.2",
  "smol_str",
  "tracing",
@@ -5888,7 +5934,7 @@ checksum = "9440ea3e5aeabb0ac63af70daf835274065238cdd0cec83418f417eae38bacee"
 
 [[package]]
 name = "xtask"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "figcraft-engine",
  "serde_json",

Cargo.toml

@@ -6,7 +6,7 @@ exclude = ["plugins"]
 # default-members = ["crates/*", "apps/figcraft", "apps/figcraft-cli", "xtask"]
 
 [workspace.package]
-version = "0.6.0"
+version = "0.7.0"
 edition = "2024"
 license = "MIT OR Apache-2.0"
 rust-version = "1.95"
@@ -32,6 +32,9 @@ figcraft-mcp = { path = "crates/mcp" }
 figcraft-collab-net = { path = "crates/collab-net" }
 figcraft-plugin = { path = "crates/plugin" }
 
+# Which paths stored in a document may be followed (craft-libs).
+craft-docpath = { version = "0.1.0", git = "https://github.com/storytold/craft-libs", rev = "82a24b006eefa036b43c09a67fb9a3fbd17ffe63" }
+
 # foundation
 kurbo = { version = "0.13", features = ["serde"] }
 thiserror = "2"

NOTICE

@@ -20,3 +20,34 @@ licence texts.
 Rust crate dependencies keep their own licenses (MIT, Apache-2.0, BSD, ISC, Zlib, OFL for egui's
 default fonts, CDLA-Permissive-2.0 for the root certificate list webpki-roots compiles in, and
 similar permissive licenses); see each crate's metadata.
+
+Linux Wayland window decorations
+-------------------------------
+sctk-adwaita 0.10.1 (https://github.com/PolyMeilex/sctk-adwaita,
+commit d5f343c45c04d4a026db57f76760819b7325db00) is used by winit on Linux
+for vector window controls. Its title-font features are disabled: no Cantarell
+font is embedded by this dependency and no font file is added to this repo.
+
+sctk-adwaita's MIT licence:
+
+MIT License
+
+Copyright (c) 2022 Bartłomiej Maryńczak
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -10,7 +10,7 @@
 <h1 align="center">FigCraft</h1>
 
 <p align="center">
-  <b>Interface design; an open-source, clean-room reimplementation of Figma, rebuilt in pure Rust.</b><br>
+  <b>Interface design and prototyping: open source, collaborative and built in pure Rust.</b><br>
   Frames, auto layout, components and variants, vector networks, styles, variables and prototypes,<br>
   in a native app that opens instantly and works offline. Open source, and yours.
 </p>
@@ -62,7 +62,7 @@
   <tr>
     <td width="25%" valign="top">
       <h3>🎛️ Familiar by design</h3>
-      The toolbar, layers panel, Design panel, menus and shortcuts sit where your hands expect them. If you know Figma, you already know FigCraft.
+      The toolbar, layers panel, Design panel, menus and shortcuts sit right where your hands expect them.
     </td>
     <td width="25%" valign="top">
       <h3>⚡ Native and fast</h3>
@@ -228,7 +228,7 @@ The desktop app also offers a loopback-only control channel (`figcraft --control
 - **Runs in the browser:** the whole engine and UI compile to WebAssembly.
 - **Accessible:** screen readers get names, roles, values and states for the tools, layer rows, fields, dropdowns, tabs and menus (AccessKit on desktop), F6 moves the keyboard between the toolbar, layers, canvas and properties (Tab within them, Escape back to the canvas), the system's reduce-motion setting is honoured, and panel text meets WCAG AA contrast in both themes.
 - **Languages:** English, Russian and Turkish (reviewed by native speakers), and Spanish, French, German, Brazilian Portuguese, Japanese, Korean, Simplified Chinese, Czech and Indonesian drafts, picked in Preferences or taken from the system or browser and switched live; adding a language is one catalog file ([`docs/translating.md`](docs/translating.md)).
-- **Plugins:** sandboxed WebAssembly plugins (a metered, pure-Rust interpreter with a memory cap and no file or network access, in the browser too) that act through the same commands, each run one undo step, within the permissions their manifest asks for. A Rust SDK and two example plugins are in [`plugins/`](plugins); see [`docs/plugins.md`](docs/plugins.md).
+- **Plugins:** sandboxed WebAssembly plugins (a metered, pure-Rust interpreter with a memory cap and no file or network access, in the browser too) that act through the same commands, each run one undo step, within the permissions their manifest asks for. A Rust SDK and three example plugins are in [`plugins/`](plugins); see [`docs/plugins.md`](docs/plugins.md).
 - **Live sessions (preview):** share the open file from the app (Share ▸ Start sharing: online through a server, or on your local network), give the others the short join code it shows (or the invite link), and edit it together: everyone's changes sync live, with cursors, selections, avatars and follow, and undo takes back only your own changes. Others join from the desktop app (invite links open it) or from the browser build. See [`docs/collab-protocol.md`](docs/collab-protocol.md).
 - **A server of your own (preview):** `figcraft-server` keeps a team's files, publishes them from the app (File ▸ Publish to server…, or Share ▸ Online with your server in Preferences) and hands out share links and join codes that let people edit or only view; files survive restarts and apps reconnect where they were. No accounts yet: links are the access. Releases ship it for Linux, and the desktop app joins over `wss://`; [hosting it on a rented Linux server](docs/server.md#deploy-on-a-linux-server) takes a systemd unit and Caddy or nginx (or Docker). See [`docs/server.md`](docs/server.md).
 - **Never crashes:** no `unwrap`, `expect` or `panic` in shipped code, enforced by clippy; commands run behind a guard so a bug fails one action, not your session.
@@ -262,7 +262,7 @@ New contributors and AI agents: start with [`AGENTS.md`](AGENTS.md), then [`docs
 Installers for macOS (universal, signed and notarized), Windows (x64, x86 and arm64), Linux (AppImage, `.deb`, `.rpm`, Flatpak and tarball), FreeBSD and the web are attached to each [GitHub release](https://github.com/storytold/figcraft/releases). Maintainers: [`docs/releasing.md`](docs/releasing.md) explains how releases are built, signed and published.
 
 > [!IMPORTANT]
-> **Status:** FigCraft is in **alpha**: about 49% of the way to replacing Figma for real work, by our own estimate. Nearly all of Figma's main menu is wired ([`docs/parity-checklist.md`](docs/parity-checklist.md)) and the core editor works end to end, but FigCraft opens `.fig` files only best effort, has only a first preview of multiplayer (live sessions hosted from the app or a self-hosted server, with per-person undo and share links to edit or to view; no accounts, teams or cloud yet), runs its own WebAssembly plugins rather than Figma's, and hasn't been checked against real Figma documents. The honest, area-by-area picture is in the [roadmap](ROADMAP.md) and [`docs/target-app-parity.md`](docs/target-app-parity.md). Expect rough edges and please file issues, or tell us what broke on [Discord](https://discord.gg/artcraft).
+> **Status:** FigCraft is in **alpha**: about 49% of the way to replacing proprietary tools for real work, by our own estimate. Nearly all tracked interface design actions in the menu checklist are wired ([`docs/parity-checklist.md`](docs/parity-checklist.md)) and the core editor works end to end, but FigCraft opens `.fig` files only best effort, has only a first preview of multiplayer (live sessions hosted from the app or a self-hosted server, with per-person undo and share links to edit or to view; no accounts, teams or cloud yet), runs its own WebAssembly plugins, and hasn't been checked against real design documents. The honest, area-by-area picture is in the [roadmap](ROADMAP.md) and [`docs/target-app-parity.md`](docs/target-app-parity.md). Expect rough edges and please file issues, or tell us what broke on [Discord](https://discord.gg/artcraft).
 
 ## Privacy and online sharing
 
@@ -348,8 +348,6 @@ ArtCraft Team and are not covered by this license. They may be used only unmodif
 part of this repository and FigCraft, under [`docs/brand/LICENSE-brand.txt`](docs/brand/LICENSE-brand.txt).
 Forks and modified versions must remove them.
 
-<sub>Figma is a trademark of Figma, Inc. FigCraft is an independent, open-source project and is not affiliated with, sponsored by or endorsed by Figma, Inc.; the name is used only to describe the workflows FigCraft is compatible with.</sub>
-
 <p align="center">
   <a href="https://getartcraft.com/"><img alt="ArtCraft" src="https://raw.githubusercontent.com/storytold/vectorcraft/main/docs/brand/artcraft-mark.png" width="28"></a><br>
   <sub>Made by the <a href="https://getartcraft.com/">ArtCraft</a> team and community.</sub>

ROADMAP.md

@@ -2,7 +2,7 @@
 
 **Stage: alpha** · next: beta, ~26 points and ~162–292 h away (one Opus 5.5 agent; ~33–67 h wall-clock with 5 agents)
 
-> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-17 · **Change:** minor (number variables in the text content picker (#629); frames and sections convert into each other (#719); bounded canvas pan overscan; community fixes from #478 up and a control-channel fix (#589); bounded canvas pan overscan; Typography spacing icons support scrubbing (#373); font scans skip named pipes; system theme on first run; recent files as cards with thumbnails on the home screen; community fixes: lost images reported on loading (#207), SVG import budgets (#190), Leptos code (#223), full screen (#227), server snapshots readable again (#188), owner-only preferences (#200), ruzstd 0.9.1 (#182), layer cycle repair (#205), batch rollback, Direct3D 12 on Windows, plugin metering (#192); vector edit mode regions: hover hatch, selection and drag; SVG/PDF exports refuse over-depth documents (#208); bounded MCP/control framing, connections and queues (#201); plugin log limits (#191); live-session revert guard (#198); attached MCP no longer replays after a lost reply (#194); repeat command recursion fix; the Layout panel's constrain-proportions link scales the other side, #220; core editor leftovers: component playground, auto gap handles, variables inside styles, inner shadows and background blur on groups, command-made text readable on dark pages, a one-step frame/group convert, delays on mouse triggers and manual overlay offsets, wrapped-line alignment; `.fig` export: instance sizes, variables with modes, shared styles, variable-width strokes; starter templates, a Templates tab and Getting started tips on the home screen; your online files; everyday editing partials: number fields, outline options, Hide when publishing, cursors, panel widths, dark pages; sharing with a join code; text box sizes measured against documents re-saved by other software; live sessions per document; .fig export checked by opening written files in other software; a public figcraft-server: open hosting, owner tokens, per-address limits, idle expiry, moderation, install.sh; experimental .fig export; keyboard shortcut parity suite and bindings; Simplified Chinese draft catalog; Latin American Spanish overlay; prototyping tail: gamepad triggers, widgets in prototypes, mode lookups; plugin directory on figcraft-server; Japanese and Korean draft catalogs and CJK UI fonts; plugin widgets and the plugin panel tail; French, German and Brazilian Portuguese draft catalogs; cursor chat and spotlight in live sessions; layers and assets panels behaviour suite and fixes; vector multi-edit and edit tail; dev resources links; extended collections tail; branch version history and finer list merges; headline percentages recomputed from the area table: feature breadth ~84%, core ~94%, mainstream ~50%; text lists, hanging punctuation and decoration styles; comments and version history behaviour suite and fixes; canvas navigation, guides and grids behaviour suite and fixes; export and inspect behaviour suite and fixes; .fig import: editable vector networks and more layer kinds; shapes and vector behaviour suite and fixes; paint and effects behaviour suite and fixes; frames, groups, sections and masks behaviour suite and fixes; styles and variables behaviour suite and fixes; prototyping behaviour suite and fixes; components behaviour suite and fixes; embedded image colour profiles; layers panel keyboard: F2 rename, Shift+F10 context menu, keyboard box selection, 10k-layer QA; per-side stroke weight variables; text behaviour suite: CJK line breaking, metrics, vertical trim; selection and transform behaviour suite and fixes; `.fig` import, best effort; Windows QA pass with eight fixes; auto layout behaviour suite and fixes; Display P3: gamut warning and soft-proof (true P3 blocked upstream); several windows; localization layer with a draft Spanish catalog; hosting figcraft-server: wss in the desktop app, server releases, deployment guide; plugin panels and settings; canvas fixes: boolean hit testing on the result, group drags, frame outlines and slices; code connect; stretch and scatter brushes, pen pressure; text on a path and pattern fills; team libraries on the server and swap library; branches: create, update from main, review and merge; animated GIF fills and TIFF images; Open recent, outlines for the selection and mask outlines: menu breadth 100%; extended collections, variables import/export, gradient stop and variant bindings; feature breadth ~80%; ready ~49%) · **Target:** Figma Design (desktop app 126.10.7)
+> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-17 · **Change:** minor (community batch #753: Selection colors, smart-selection spacing, a Present tab; language table re-measured from the catalogs; community fixes from #524 up (55 PRs: `.fig` import fidelity, paste from other apps, the Actions palette, editor fixes, server limits) and a boolean-op crash guard; number variables in the text content picker (#629); frames and sections convert into each other (#719); bounded canvas pan overscan; community fixes from #478 up and a control-channel fix (#589); bounded canvas pan overscan; Typography spacing icons support scrubbing (#373); font scans skip named pipes; system theme on first run; recent files as cards with thumbnails on the home screen; community fixes: lost images reported on loading (#207), SVG import budgets (#190), Leptos code (#223), full screen (#227), server snapshots readable again (#188), owner-only preferences (#200), ruzstd 0.9.1 (#182), layer cycle repair (#205), batch rollback, Direct3D 12 on Windows, plugin metering (#192); vector edit mode regions: hover hatch, selection and drag; SVG/PDF exports refuse over-depth documents (#208); bounded MCP/control framing, connections and queues (#201); plugin log limits (#191); live-session revert guard (#198); attached MCP no longer replays after a lost reply (#194); repeat command recursion fix; the Layout panel's constrain-proportions link scales the other side, #220; core editor leftovers: component playground, auto gap handles, variables inside styles, inner shadows and background blur on groups, command-made text readable on dark pages, a one-step frame/group convert, delays on mouse triggers and manual overlay offsets, wrapped-line alignment; `.fig` export: instance sizes, variables with modes, shared styles, variable-width strokes; starter templates, a Templates tab and Getting started tips on the home screen; your online files; everyday editing partials: number fields, outline options, Hide when publishing, cursors, panel widths, dark pages; sharing with a join code; text box sizes measured against documents re-saved by other software; live sessions per document; .fig export checked by opening written files in other software; a public figcraft-server: open hosting, owner tokens, per-address limits, idle expiry, moderation, install.sh; experimental .fig export; keyboard shortcut parity suite and bindings; Simplified Chinese draft catalog; Latin American Spanish overlay; prototyping tail: gamepad triggers, widgets in prototypes, mode lookups; plugin directory on figcraft-server; Japanese and Korean draft catalogs and CJK UI fonts; plugin widgets and the plugin panel tail; French, German and Brazilian Portuguese draft catalogs; cursor chat and spotlight in live sessions; layers and assets panels behaviour suite and fixes; vector multi-edit and edit tail; dev resources links; extended collections tail; branch version history and finer list merges; headline percentages recomputed from the area table: feature breadth ~84%, core ~94%, mainstream ~50%; text lists, hanging punctuation and decoration styles; comments and version history behaviour suite and fixes; canvas navigation, guides and grids behaviour suite and fixes; export and inspect behaviour suite and fixes; .fig import: editable vector networks and more layer kinds; shapes and vector behaviour suite and fixes; paint and effects behaviour suite and fixes; frames, groups, sections and masks behaviour suite and fixes; styles and variables behaviour suite and fixes; prototyping behaviour suite and fixes; components behaviour suite and fixes; embedded image colour profiles; layers panel keyboard: F2 rename, Shift+F10 context menu, keyboard box selection, 10k-layer QA; per-side stroke weight variables; text behaviour suite: CJK line breaking, metrics, vertical trim; selection and transform behaviour suite and fixes; `.fig` import, best effort; Windows QA pass with eight fixes; auto layout behaviour suite and fixes; Display P3: gamut warning and soft-proof (true P3 blocked upstream); several windows; localization layer with a draft Spanish catalog; hosting figcraft-server: wss in the desktop app, server releases, deployment guide; plugin panels and settings; canvas fixes: boolean hit testing on the result, group drags, frame outlines and slices; code connect; stretch and scatter brushes, pen pressure; text on a path and pattern fills; team libraries on the server and swap library; branches: create, update from main, review and merge; animated GIF fills and TIFF images; Open recent, outlines for the selection and mask outlines: menu breadth 100%; extended collections, variables import/export, gradient stop and variant bindings; feature breadth ~80%; ready ~49%) · **Target:** Figma Design (desktop app 126.10.7)
 
 FigCraft is a clean-room, open-source, pure-Rust reimplementation of the Figma design workflow,
 native on macOS, Windows, Linux and FreeBSD and in the browser, fully drivable by agents through
@@ -13,7 +13,7 @@ start with [`docs/gaps.md`](docs/gaps.md).
 
 | | Value | Kind |
 |---|---|---|
-| Menu/command breadth | **100%** (211 / 211) | measured, [`docs/parity-checklist.md`](docs/parity-checklist.md) (`cargo xtask parity`) |
+| Menu/command breadth | **100%** (212 / 212) | measured, [`docs/parity-checklist.md`](docs/parity-checklist.md) (`cargo xtask parity`) |
 | Feature breadth | **~85%** (core editor ~94%) | estimated, [`docs/target-app-parity.md`](docs/target-app-parity.md) |
 | Ready for real work | **~53%** | estimated, same doc (written dimension weights and scores) |
 | Essentials user | **~59%** | estimated: core features 77.8% × 0.92 launch/stability × 0.94 discoverability × 0.88 opening files people send ([method](docs/target-app-parity.md#essentials-user)) |
@@ -99,25 +99,25 @@ native speakers' reviews of the six language drafts need people.
 | Language | Code | Strings | Status |
 |---|---|---|---|
 | English | en | 100% | full |
-| Simplified Chinese | zh-Hans | 100% | draft (needs native review) |
-| Spanish | es, es-419 | 100% (es-419: an overlay of 98 entries) | draft (needs native review) |
+| Simplified Chinese | zh-Hans | 95% | draft (needs native review) |
+| Spanish | es, es-419 | 100% (es-419: an overlay of 101 entries) | draft (needs native review) |
 | Hindi | hi | 0% | none |
 | Arabic | ar | 0% | none |
-| French | fr | 100% | draft (needs native review) |
-| Portuguese (Brazil) | pt-BR | 100% | draft (needs native review) |
-| Indonesian | id | 0% | none |
-| Japanese | ja | 100% | draft (needs native review) |
-| German | de | 100% | draft (needs native review) |
-| Korean | ko | 100% | draft (needs native review) |
+| French | fr | 95% | draft (needs native review) |
+| Portuguese (Brazil) | pt-BR | 95% | draft (needs native review) |
+| Indonesian | id | 99% | draft (needs native review) |
+| Japanese | ja | 99% | draft (needs native review) |
+| German | de | 96% | draft (needs native review) |
+| Korean | ko | 95% | draft (needs native review) |
 | Vietnamese | vi | 0% | none |
 
-Also shipped: Swedish (`sv`: every UI string, 120 of 588 command labels and menu wordings; native review welcome). Figma ships English, Japanese, Korean, French, German, Spanish and Portuguese
+Percentages measured 2026-10-17 over 2,272 entries (strings added since a draft show English). Also shipped: Russian (`ru`, 99%, reviewed by VanTan), Swedish (`sv`, 99.6%, command labels since 2026-10-17; native review welcome), Turkish (`tr`, 99%) and Czech (`cs`, 99%, draft). Figma ships English, Japanese, Korean, French, German, Spanish and Portuguese
 (Brazil); FigCraft has the localization layer, English and Spanish (Spain and Latin America),
-French, German, Brazilian Portuguese, Japanese, Korean and Simplified Chinese drafts (Preferences ▸
+French, German, Brazilian Portuguese, Japanese, Korean, Simplified Chinese and Indonesian drafts (Preferences ▸
 Language; Traditional Chinese has no catalog; CJK UI
 text uses an installed CJK font, loaded only when needed; adding a language:
 [`docs/translating.md`](docs/translating.md)). Document text in any script (bidi, Arabic shaping,
-IME) already works. Detail: [`docs/localization-parity.md`](docs/localization-parity.md).
+IME) already works (macOS IME composition fixed for #747, not yet checked on a Mac). Detail: [`docs/localization-parity.md`](docs/localization-parity.md).
 
 ## Upcoming
 
@@ -131,6 +131,7 @@ Ranked; detail and milestones in [`docs/roadmap.md`](docs/roadmap.md).
 
 ## Progress log
 
+- **2026-10-17** · Control channel while the window is minimised (M8, #720): a minimised or covered window answers every request that acts on the app's state (edits, `ui.inspect`, `ui.pointer`, `ui.key`, `ui.type`, `ui.set`, `app.quit`…) without drawing, and what needs a drawn frame (`ui.screenshot`, `ui.input`, `window.new`) is an error at once; before, those waited up to 60 s and held up every later request on the connection (an attached agent's `inspect_ui` or window screenshot stalled until the window came back). Measured on Windows 11, minimised: requests ~100 ms each (eframe wakes a minimised window at most ten times a second; ~2 ms on screen), a window screenshot fails in ~100 ms instead of 60 s, idle CPU 0. Numbers unchanged.
 - **2026-10-17** · Number variables on text content (M3, #629): the Typography section's variable picker also lists number variables for a text layer's content, as the engine already accepted (the text shows the number, e.g. 42.5, and follows the variable). Other text fields keep their own types. Numbers unchanged.
 - **2026-10-17** · Frames and sections convert into each other (M1, #719): `object.convertToSection` turns a frame on the page or in a section into a section in place (same box, name, fill and layers, which stay where they are; what only a frame has goes: auto layout, clipping, layout grids, guides, scrolling), and `object.convertToFrame` now also turns a section into a frame that keeps its fill and doesn't clip, so the look stays. Nested frames, instances, main components and sections holding sections are refused with the reason; one undo step each. Both are in the canvas context menu (Convert to section / Convert to frame) and in Spanish. Numbers unchanged.
 - **2026-10-14** · Corner handles win over the corner-radius handles (M1, #292): a press on the inner half of a corner handle's square picked the radius handle 10 px in, so the drag neither resized nor (dragging outward) rounded anything. Inside the drawn square the corner now resizes both sides (in ratio with Shift or the link); further in the radius handle still answers. Regression test in the transform behaviour suite. Numbers unchanged.
@@ -315,6 +316,9 @@ Ranked; detail and milestones in [`docs/roadmap.md`](docs/roadmap.md).
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-17 | minor | Community batch #753 (10 PRs): Selection colors for mixed selections (#403); smart-selection spacing fields and canvas handles (#402); a Present tab with device and scale controls (#537); adding auto layout to an empty frame keeps its size (#369); `node.set` applies auto layout keys to frames only and warns about font styles a family lacks (#603); canvas images on whole device pixels (#359); Adwaita window controls on Wayland without server decorations (#592, not run on GNOME or KDE by the maintainers); the keyboard shortcuts panel closes on the home screen (#548); macOS paste modifiers in tests (#750); credits column tests (#347). `cargo xtask parity` re-run: 212 / 212 menu items (100%; the catalog gained View ▸ Full screen with #227 on 2026-10-14), 561 commands. Language table re-measured from the catalogs (2,272 entries): the drafts read 95–99% (strings added since 2026-10-12 show English), Indonesian has a draft (99%; it read none), and Russian, Swedish (its command labels from #599), Turkish and Czech are listed with their counts. Per-area parity rows for the day's landings in `docs/gaps.md`, `target-app-parity.md` and the area docs. Numbers unchanged |
+| 2026-10-17 | minor | Control channel while the window is minimised (M8, #720): a minimised or covered window answers every request that acts on the app's state (edits, `ui.inspect`, `ui.pointer`, `ui.key`, `ui.type`, `ui.set`, `app.quit`…) without drawing, and what needs a drawn frame (`ui.screenshot`, `ui.input`, `window.new`) is an error at once; before, those waited up to 60 s and held up every later request on the connection (an attached agent's `inspect_ui` or window screenshot stalled until the window came back). Measured on Windows 11, minimised: requests ~100 ms each (eframe wakes a minimised window at most ten times a second; ~2 ms on screen), a window screenshot fails in ~100 ms instead of 60 s, idle CPU 0. Numbers unchanged. |
+| 2026-10-17 | minor | Community fixes from #524 up (batches #727, #728, #733, #735, #736 and #729; 55 PRs) and a crash guard. `.fig` import: explicit instance identity, overrides by key, text style precedence, grid track sizes, slot content, connector labels, skip ink, paragraph options and hanging lists, list start numbers, vertical trim, per-point stroke joins, text on a path, image adjustments and embedded images; large files open within budgets from the file's own size; an import report after opening; imported bytes stay out of the command journal. Files and paste: save a copy as `.fig`; Cmd/Ctrl+V pastes images copied in other apps and layers copied from another design app (`edit.pasteDesignLayers`); paste over and paste properties; clipboard reads on Linux and the BSDs time out after 2 s. Editor: live font preview on hover; Shift+I and Resources open Assets; Shift-drag moves the selection; thin strokes take a nearby double-click; dropped points merge; Flatten keeps open paths; the Actions palette gets tabs, ranked search, a keyboard highlight and recents; the colour picker opens on a new fill or stroke; text strokes follow their alignment; selection highlights after line breaks; a draggable pages/layers divider; variant properties reorder by drag; submenus keep their hover with a safe triangle; menu actions that need a value ask for it; File ▸ Rename edits the name in place. Engine: bad paint indexes, non-finite geometry and pages in copy/cut are refused; a param naming a layer says so when it isn't one; a CLI script is one undo step and resolves `$step`. Server and collaboration: message limits follow `max_file_mb` (client capped at 1 GiB); a damaged generation field no longer drops flushed edits; the web build joins a session from a `#join=` link. Also Swedish command labels, Nix CI through the shared workflow, paint bounds once per render, and a guard that turns a panic inside the boolean-op library into bad input (the stroke draws unclipped). Numbers unchanged. |
 | 2026-10-17 | minor | Number variables on text content (M3, #629): the Typography section's variable picker also lists number variables for a text layer's content, as the engine already accepted (the text shows the number, e.g. 42.5, and follows the variable). Other text fields keep their own types. Numbers unchanged. |
 | 2026-10-17 | minor | Frames and sections convert into each other (M1, #719): `object.convertToSection` turns a frame on the page or in a section into a section in place (same box, name, fill and layers, which stay where they are; what only a frame has goes: auto layout, clipping, layout grids, guides, scrolling), and `object.convertToFrame` now also turns a section into a frame that keeps its fill and doesn't clip, so the look stays. Nested frames, instances, main components and sections holding sections are refused with the reason; one undo step each. Both are in the canvas context menu (Convert to section / Convert to frame) and in Spanish. Numbers unchanged. |
 | 2026-10-16 | minor | Community fixes from #478 up (batches #591, #598, #602; 69 PRs) and a control-channel fix: a line that isn't JSON now ends a `--control` connection, so a web page can't drive the app through a browser request (#589). Highlights: page copies keep navigation, flows, prototype settings and guides; Find and Replace keeps line endings and case-insensitive matches; text hyperlinks survive import and export; recent colours record only what was picked; MCP screenshots respect `maxSize`; Swedish catalog (UI strings), Czech plurals; bounded canvas overscan while panning; Korean fallback at the run's weight; many vector-edit, guide, page and .fig round-trip fixes. Numbers unchanged |

apps/figcraft-cli/src/args.rs

@@ -1,5 +1,6 @@
 //! Minimal std-only argument parsing: positionals, `--key value` / `--key=value` / `-o value`
-//! options, and boolean `--flag`s. Unknown options are usage errors.
+//! options (given again: the last counts, or all with [`Args::values`]), and boolean `--flag`s.
+//! Unknown options are usage errors.
 
 use std::collections::BTreeMap;
 
@@ -8,7 +9,7 @@ use crate::{CliError, CliResult};
 #[derive(Debug, Default)]
 pub struct Args {
     pub positional: Vec<String>,
-    values: BTreeMap<String, String>,
+    values: BTreeMap<String, Vec<String>>,
     flags: Vec<String>,
 }
 
@@ -34,7 +35,7 @@ impl Args {
                     Some(v) => v,
                     None => it.next().cloned().ok_or_else(|| CliError::Usage(format!("`{arg}` needs a value")))?,
                 };
-                a.values.insert(name.to_string(), v);
+                a.values.entry(name.to_string()).or_default().push(v);
             } else if flags.contains(&name) && inline.is_none() {
                 a.flags.push(name.to_string());
             } else {
@@ -45,7 +46,12 @@ impl Args {
     }
 
     pub fn value(&self, k: &str) -> Option<String> {
-        self.values.get(k).cloned()
+        self.values.get(k).and_then(|v| v.last()).cloned()
+    }
+
+    /// Every value of an option that may be given more than once, in order.
+    pub fn values(&self, k: &str) -> &[String] {
+        self.values.get(k).map_or(&[], Vec::as_slice)
     }
 
     pub fn flag(&self, k: &str) -> bool {
@@ -62,9 +68,9 @@ impl Args {
     /// PDF print options: `--bleed LENGTH` (points, or "3mm", "0.125in"), `--crop-marks`,
     /// `--bleed-marks`, `--cmyk`.
     pub fn print(&self) -> CliResult<figcraft_doc::PrintSettings> {
-        let bleed = match self.values.get("bleed") {
+        let bleed = match self.value("bleed") {
             None => 0.0,
-            Some(s) => figcraft_doc::PrintSettings::parse_length(s)
+            Some(s) => figcraft_doc::PrintSettings::parse_length(&s)
                 .filter(|b| *b <= figcraft_doc::PrintSettings::MAX_BLEED)
                 .ok_or_else(|| CliError::Usage(format!("--bleed takes points or a length like 3mm or 0.125in (up to 2in), got `{s}`")))?,
         };
@@ -72,7 +78,7 @@ impl Args {
     }
 
     pub fn scale(&self) -> CliResult<f64> {
-        match self.values.get("scale") {
+        match self.value("scale") {
             None => Ok(1.0),
             Some(s) => s
                 .trim_end_matches('x')
@@ -85,7 +91,7 @@ impl Args {
 
     /// A comma-separated list of whole numbers (`--layers 1000,10_000`).
     pub fn usizes(&self, k: &str, default: &[usize]) -> CliResult<Vec<usize>> {
-        match self.values.get(k) {
+        match self.value(k) {
             None => Ok(default.to_vec()),
             Some(s) => s
                 .split(',')
@@ -110,6 +116,10 @@ mod tests {
         assert_eq!(a.value("o").as_deref(), Some("out"));
         assert_eq!(a.scale().unwrap(), 2.0);
         assert!(a.flag("json"));
+        let a = Args::parse(&v(&["--root", "a", "--root=b"]), &["root"], &[]).unwrap();
+        assert_eq!(a.values("root"), ["a", "b"]);
+        assert_eq!(a.value("root").as_deref(), Some("b"));
+        assert!(a.values("none").is_empty());
     }
 
     #[test]

apps/figcraft-cli/src/files.rs

@@ -29,9 +29,20 @@ fn image_format(e: &str) -> Option<ExportFormat> {
     }
 }
 
+/// Writes through [`figcraft_engine::file_access`] when automation roots are in force, so a
+/// confined run can only write inside a write root (#833).
+///
+/// Unconfined it writes with `std::fs::write`, as it always did. `file_access::write` stages the
+/// bytes and renames them into place, which **replaces** a symbolic link at `path` instead of
+/// writing through it to its target -- a change of behaviour for anyone whose output path is a
+/// link, and nothing to do with confinement. Inside a root the staged write is the right one:
+/// `Roots::check` has already refused a link that leads out of the root.
 fn write(path: &str, bytes: &[u8]) -> CliResult<()> {
     if let Some(dir) = Path::new(path).parent().filter(|d| !d.as_os_str().is_empty()) {
-        std::fs::create_dir_all(dir).map_err(|e| CliError::Failed(format!("{}: {e}", dir.display())))?;
+        figcraft_engine::file_access::create_dir_all(dir).map_err(|e| CliError::Failed(e.to_string()))?;
+    }
+    if figcraft_engine::file_access::current().is_some() {
+        return figcraft_engine::file_access::write(path, bytes).map_err(|e| CliError::Failed(e.to_string()));
     }
     std::fs::write(path, bytes).map_err(|e| CliError::Failed(format!("{path}: {e}")))
 }
@@ -155,6 +166,7 @@ pub fn info(path: &str, as_json: bool) -> CliResult<ExitCode> {
             Some(json!({"id": p, "name": pn.name, "nodes": nodes, "topLevel": pn.children.len(), "frames": frames}))
         })
         .collect();
+    let missing = figcraft_engine::fonts::missing(&doc);
     let v = json!({
         "file": path,
         "name": doc.name,
@@ -164,6 +176,7 @@ pub fn info(path: &str, as_json: bool) -> CliResult<ExitCode> {
         "variables": doc.variables.variables.len(),
         "images": doc.images.len(),
         "notes": notes,
+        "missingFonts": missing.iter().map(|m| json!({"family": m.family, "layers": m.layers})).collect::<Vec<_>>(),
     });
     if as_json {
         println!("{}", serde_json::to_string_pretty(&v).unwrap_or_default());
@@ -187,6 +200,10 @@ pub fn info(path: &str, as_json: bool) -> CliResult<ExitCode> {
             println!("  {} {} \"{}\" {}×{}", f["id"], f["type"].as_str().unwrap_or(""), f["name"].as_str().unwrap_or(""), f["width"], f["height"]);
         }
     }
+    for m in &missing {
+        let layers = if m.layers == 1 { "text layer" } else { "text layers" };
+        println!("missing font \"{}\": {} {layers} (drawn in a fallback font)", m.family, m.layers);
+    }
     Ok(ExitCode::SUCCESS)
 }
 
@@ -238,7 +255,7 @@ pub fn export(file: &str, out: &str, t: &Target) -> CliResult<ExitCode> {
         println!("{out}");
         return Ok(ExitCode::SUCCESS);
     }
-    std::fs::create_dir_all(out).map_err(|e| CliError::Failed(format!("{out}: {e}")))?;
+    figcraft_engine::file_access::create_dir_all(out).map_err(|e| CliError::Failed(e.to_string()))?;
     let ids = match target {
         Some(t) => vec![t],
         None => {
@@ -323,7 +340,8 @@ pub fn parse_script(text: &str) -> Result<Vec<(String, Value)>, String> {
 }
 
 pub fn run_script(script: &str, input: Option<&str>, out: Option<&str>) -> CliResult<ExitCode> {
-    let text = std::fs::read_to_string(script).map_err(|e| CliError::Failed(format!("{script}: {e}")))?;
+    let bytes = figcraft_engine::file_access::read(script).map_err(|e| CliError::Failed(e.to_string()))?;
+    let text = String::from_utf8(bytes).map_err(|_| CliError::Failed(format!("{script}: not UTF-8")))?;
     let steps = parse_script(&text).map_err(|e| CliError::Failed(format!("{script}: {e}")))?;
     let mut s = match input {
         Some(path) => {
@@ -333,17 +351,32 @@ pub fn run_script(script: &str, input: Option<&str>, out: Option<&str>) -> CliRe
         }
         None => Session::new(),
     };
-    for (i, (cmd, params)) in steps.iter().enumerate() {
-        let r = s.execute(cmd, params);
-        s.ui_requests.clear();
-        match r {
-            Ok(v) => println!("{}", json!({"step": i, "command": cmd, "ok": true, "result": v})),
-            Err(e) => {
-                println!("{}", json!({"step": i, "command": cmd, "ok": false, "error": e.to_string()}));
-                eprintln!("error: step {i} ({cmd}) failed: {e}");
-                return Ok(ExitCode::from(1));
-            }
+    // One undo step and all-or-nothing, the way the same commands behave through `command.batch`
+    // (MCP, the control channel, plugins): `{"$step": n}` resolves against the steps before it, and
+    // a step that fails takes the whole script back instead of leaving the earlier steps applied.
+    // The result lines are held back until the script is through, so none of them reports work that
+    // was rolled back.
+    let mut results: Vec<Value> = Vec::with_capacity(steps.len());
+    let mut failed_at = 0;
+    let outcome = s.grouped(&format!("run {script}"), |s| {
+        for (i, (cmd, params)) in steps.iter().enumerate() {
+            failed_at = i;
+            let v = s.batch_step(&results, i, cmd, params)?;
+            s.ui_requests.clear();
+            results.push(v);
         }
+        Ok(())
+    });
+    if let Err(e) = outcome {
+        let cmd = steps.get(failed_at).map_or("", |(cmd, _)| cmd.as_str());
+        let i = failed_at;
+        println!("{}", json!({"step": i, "command": cmd, "ok": false, "error": e.to_string(), "rolledBack": true}));
+        eprintln!("error: step {i} ({cmd}) failed: {e}");
+        eprintln!("the script's document changes were rolled back");
+        return Ok(ExitCode::from(1));
+    }
+    for (i, ((cmd, _), v)) in steps.iter().zip(&results).enumerate() {
+        println!("{}", json!({"step": i, "command": cmd, "ok": true, "result": v}));
     }
     if let Some(out) = out {
         let ds = s.ds().map_err(|e| CliError::Failed(e.to_string()))?;
@@ -422,4 +455,62 @@ mod tests {
         assert_eq!(std::fs::read_dir(&dir).unwrap().count(), 2);
         std::fs::remove_dir_all(dir).unwrap();
     }
+
+    fn temp_dir(tag: &str) -> std::path::PathBuf {
+        let stamp = std::time::SystemTime::now().duration_since(std::time::UNIX_EPOCH).unwrap().as_nanos();
+        let dir = std::env::temp_dir().join(format!("figcraft-cli-{tag}-{}-{stamp}", std::process::id()));
+        std::fs::create_dir(&dir).unwrap();
+        dir
+    }
+
+    /// A script resolves `{"$step": n}` like the same commands through `command.batch`. Each step
+    /// used to run on its own, so the reference reached `parent` unresolved, `node.create` read it
+    /// as "no parent" and the layer landed on the page — with every step reporting success.
+    #[test]
+    fn a_script_puts_a_layer_in_a_layer_an_earlier_step_made() {
+        let dir = temp_dir("run-step");
+        let script = dir.join("script.json");
+        std::fs::write(
+            &script,
+            r#"[
+                {"command": "node.create", "params": {"type": "frame", "name": "Card", "x": 0, "y": 0, "width": 200, "height": 100}},
+                {"command": "node.create", "params": {"type": "rectangle", "name": "child", "parent": {"$step": 0}, "x": 10, "y": 10, "width": 20, "height": 20}}
+            ]"#,
+        )
+        .unwrap();
+        let out = dir.join("out.figcraft");
+        run_script(script.to_str().unwrap(), None, Some(out.to_str().unwrap())).unwrap();
+
+        let mut s = Session::empty();
+        s.execute("file.open", &json!({"path": out.to_str().unwrap()})).unwrap();
+        let doc = s.doc().unwrap();
+        let page = s.page().unwrap();
+        let top = doc.node(page).unwrap().children.clone();
+        assert_eq!(top.len(), 1, "only the frame is top level, not the rectangle too");
+        assert_eq!(doc.node(top[0]).unwrap().name, "Card");
+        let inner = doc.node(top[0]).unwrap().children.clone();
+        assert_eq!(inner.len(), 1, "the rectangle went inside the frame");
+        assert_eq!(doc.node(inner[0]).unwrap().name, "child");
+        std::fs::remove_dir_all(dir).unwrap();
+    }
+
+    /// A step that fails takes the whole script back: nothing is written, and the failure says so.
+    #[test]
+    fn a_failed_step_leaves_no_output() {
+        let dir = temp_dir("run-rollback");
+        let script = dir.join("script.json");
+        std::fs::write(
+            &script,
+            r#"[
+                {"command": "node.create", "params": {"type": "frame", "name": "Card", "x": 0, "y": 0, "width": 200, "height": 100}},
+                {"command": "node.set", "params": {"ids": [99999], "props": {"name": "nope"}}}
+            ]"#,
+        )
+        .unwrap();
+        let out = dir.join("out.figcraft");
+        // The failure is the script's, not the call's: the CLI reports it and exits non-zero.
+        run_script(script.to_str().unwrap(), None, Some(out.to_str().unwrap())).unwrap();
+        assert!(!out.exists(), "a script that failed writes nothing");
+        std::fs::remove_dir_all(dir).unwrap();
+    }
 }

apps/figcraft-cli/src/main.rs

@@ -22,8 +22,9 @@ USAGE:
   figcraft-cli convert <in> <out>
   figcraft-cli render <file> -o <out.png> [--scale N] [--page NAME]
   figcraft-cli run <script.json|script.jsonl> [--in <file>] [--out <file>]
+  (info, export, convert, render and run also take --automation-read-root DIR / --automation-write-root DIR)
   figcraft-cli commands [--json] [--filter TEXT]
-  figcraft-cli mcp [--attach PORT]
+  figcraft-cli mcp [--attach PORT] [--automation-read-root DIR]... [--automation-write-root DIR]...
   figcraft-cli plugin publish <folder> --server ws://host:port/[?key=KEY]
   figcraft-cli perf [--layers N[,N...]] [--instances N[,N...]]
   figcraft-cli help | --help | --version
@@ -42,8 +43,33 @@ crop and bleed marks, CMYK colour). `run` executes a JSON array (or JSON lines)
 `plugin publish` sends a plugin folder (figcraft-plugin.json, its module, an optional assets/ folder)
 to a figcraft-server's plugin directory as a new version; the server's key comes from the address or
 the FIGCRAFT_SERVER_KEY environment variable (which keeps it out of the shell history).
+`--automation-read-root DIR` / `--automation-write-root DIR` (each may be repeated; the folders
+must exist) confine the files a subcommand touches: reads only inside a read or write root, writes
+only inside a write root, everything else refused -- so giving no write root denies writing
+altogether. They are taken by `mcp`, to confine the agent's commands, and by `info`, `export`,
+`convert`, `render` and `run`, to confine that one run; without them a subcommand reads and writes
+as the user who started it, as before. A running app confines itself: start it with
+`figcraft --control PORT` and the same flags (`--attach` refuses them).
 See docs/cli.md and docs/mcp.md.";
 
+/// The automation roots a file subcommand was given, if any. Omitting both leaves the run
+/// unconfined, as before; giving either confines every file the subcommand touches (#833).
+const ROOT_FLAGS: [&str; 2] = ["automation-read-root", "automation-write-root"];
+
+fn roots_of(a: &Args) -> CliResult<Option<figcraft_engine::file_access::Roots>> {
+    let (read, write) = (a.values("automation-read-root"), a.values("automation-write-root"));
+    if read.is_empty() && write.is_empty() {
+        return Ok(None);
+    }
+    Ok(Some(figcraft_engine::file_access::Roots::new(read, write).map_err(CliError::Failed)?))
+}
+
+/// Runs `f` confined to the roots `a` carries.
+fn confined<R>(a: &Args, f: impl FnOnce() -> CliResult<R>) -> CliResult<R> {
+    let roots = roots_of(a)?.map(std::sync::Arc::new);
+    figcraft_engine::file_access::confined(roots.as_ref(), f)
+}
+
 fn main() -> ExitCode {
     let argv: Vec<String> = std::env::args().skip(1).collect();
     match run(&argv) {
@@ -94,35 +120,38 @@ fn run(argv: &[String]) -> CliResult<ExitCode> {
             Ok(ExitCode::SUCCESS)
         }
         "info" => {
-            let a = Args::parse(rest, &[], &["json"])?;
+            let a = Args::parse(rest, &ROOT_FLAGS, &["json"])?;
             let file = a.one_positional("info <file>")?;
-            files::info(&file, a.flag("json"))
+            confined(&a, || files::info(&file, a.flag("json")))
         }
         "export" => {
-            let a = Args::parse(rest, &["format", "scale", "page", "node", "o", "out", "bleed"], &["crop-marks", "bleed-marks", "cmyk"])?;
+            let valued = [&["format", "scale", "page", "node", "o", "out", "bleed"][..], &ROOT_FLAGS[..]].concat();
+            let a = Args::parse(rest, &valued, &["crop-marks", "bleed-marks", "cmyk"])?;
             let file = a.one_positional("export <file> -o <out>")?;
             let out = a.value("o").or_else(|| a.value("out")).ok_or_else(|| CliError::Usage("export needs -o <out>".into()))?;
             let target =
                 files::Target { format: a.value("format"), scale: a.scale()?, page: a.value("page"), node: a.value("node"), print: a.print()? };
-            files::export(&file, &out, &target)
+            confined(&a, || files::export(&file, &out, &target))
         }
         "convert" => {
-            let a = Args::parse(rest, &[], &[])?;
+            let a = Args::parse(rest, &ROOT_FLAGS, &[])?;
             match a.positional.as_slice() {
-                [i, o] => files::convert(i, o),
+                [i, o] => confined(&a, || files::convert(i, o)),
                 _ => Err(CliError::Usage("convert <in> <out>".into())),
             }
         }
         "render" => {
-            let a = Args::parse(rest, &["o", "out", "scale", "page"], &[])?;
+            let valued = [&["o", "out", "scale", "page"][..], &ROOT_FLAGS[..]].concat();
+            let a = Args::parse(rest, &valued, &[])?;
             let file = a.one_positional("render <file> -o <out.png>")?;
             let out = a.value("o").or_else(|| a.value("out")).ok_or_else(|| CliError::Usage("render needs -o <out.png>".into()))?;
-            files::render(&file, &out, a.scale()?, a.value("page").as_deref())
+            confined(&a, || files::render(&file, &out, a.scale()?, a.value("page").as_deref()))
         }
         "run" => {
-            let a = Args::parse(rest, &["in", "out"], &[])?;
+            let valued = [&["in", "out"][..], &ROOT_FLAGS[..]].concat();
+            let a = Args::parse(rest, &valued, &[])?;
             let script = a.one_positional("run <script.json|.jsonl>")?;
-            files::run_script(&script, a.value("in").as_deref(), a.value("out").as_deref())
+            confined(&a, || files::run_script(&script, a.value("in").as_deref(), a.value("out").as_deref()))
         }
         "commands" => {
             let a = Args::parse(rest, &["filter"], &["json"])?;
@@ -133,11 +162,20 @@ fn run(argv: &[String]) -> CliResult<ExitCode> {
             Ok(ExitCode::SUCCESS)
         }
         "mcp" => {
-            let a = Args::parse(rest, &["attach"], &[])?;
+            let valued = [&["attach"][..], &ROOT_FLAGS[..]].concat();
+            let a = Args::parse(rest, &valued, &[])?;
             if !a.positional.is_empty() {
                 return Err(CliError::Usage("mcp takes no positional arguments".into()));
             }
-            mcp(a.value("attach").as_deref())
+            let attach = a.value("attach");
+            // The app runs the commands: only its own roots can confine them.
+            if attach.is_some() && ROOT_FLAGS.iter().any(|f| !a.values(f).is_empty()) {
+                return Err(CliError::Usage(
+                    "--attach can't take automation roots: start the app with them instead (`figcraft --control PORT --automation-read-root DIR ...`)"
+                        .into(),
+                ));
+            }
+            mcp(attach.as_deref(), roots_of(&a)?)
         }
         "plugin" => {
             let a = Args::parse(rest, &["server"], &[])?;
@@ -205,7 +243,7 @@ fn publish_plugin(folder: &str, server: &str) -> CliResult<ExitCode> {
     Ok(ExitCode::SUCCESS)
 }
 
-fn mcp(attach: Option<&str>) -> CliResult<ExitCode> {
+fn mcp(attach: Option<&str>, roots: Option<figcraft_engine::file_access::Roots>) -> CliResult<ExitCode> {
     let backend: Box<dyn figcraft_mcp::Backend> = match attach {
         Some(p) => {
             let addr = if p.contains(':') {
@@ -220,7 +258,10 @@ fn mcp(attach: Option<&str>) -> CliResult<ExitCode> {
         None => Box::new(figcraft_mcp::Headless::new()),
     };
     eprintln!("figcraft MCP server ({}) on stdio", backend.describe());
-    let mut server = figcraft_mcp::Server::new(backend);
+    if let Some(r) = &roots {
+        eprintln!("file access confined to {}", r.to_json());
+    }
+    let mut server = figcraft_mcp::Server::new(backend).with_roots(roots);
     let stdin = std::io::stdin();
     let stdout = std::io::stdout();
     server.serve(stdin.lock(), stdout.lock()).map_err(|e| format!("stdio: {e}"))?;

apps/figcraft-cli/tests/cli.rs

@@ -25,6 +25,9 @@ fn bad_arguments_exit_2_without_panicking() {
         &["render", "a", "-o"],
         &["perf", "--shapes", "lots"],
         &["mcp", "--attach", "notaport"],
+        // An attached app confines itself: roots go to `figcraft --control`.
+        &["mcp", "--attach", "7979", "--automation-read-root", "."],
+        &["mcp", "--automation-write-root"],
         &["convert", "a"],
     ] {
         let out = bin().args(args).output().unwrap();
@@ -120,9 +123,147 @@ fn mcp_over_stdio() {
     assert_eq!(lines[2]["result"]["isError"], false);
 }
 
+#[test]
+fn mcp_over_stdio_confined_to_automation_roots() {
+    let d = tmp("roots");
+    for sub in ["in", "out", "outside"] {
+        std::fs::create_dir_all(d.join(sub)).unwrap();
+    }
+    let p = |rel: &str| d.join(rel).to_string_lossy().into_owned();
+    // A root that isn't a folder stops the server before it serves.
+    let out = bin().args(["mcp", "--automation-read-root", &p("missing")]).output().unwrap();
+    assert_eq!(out.status.code(), Some(1));
+    assert!(String::from_utf8_lossy(&out.stderr).contains("--automation-read-root"));
+    let mut child = bin()
+        .args(["mcp", "--automation-read-root", &p("in"), "--automation-write-root", &p("out")])
+        .stdin(Stdio::piped())
+        .stdout(Stdio::piped())
+        .stderr(Stdio::null())
+        .spawn()
+        .unwrap();
+    {
+        let stdin = child.stdin.as_mut().unwrap();
+        let call = |id: u32, tool: &str, args: serde_json::Value| {
+            serde_json::json!({"jsonrpc": "2.0", "id": id, "method": "tools/call", "params": {"name": tool, "arguments": args}}).to_string()
+        };
+        writeln!(stdin, r#"{{"jsonrpc":"2.0","id":1,"method":"initialize","params":{{"protocolVersion":"2025-06-18"}}}}"#).unwrap();
+        writeln!(stdin, "{}", call(2, "create_node", serde_json::json!({"type": "ellipse"}))).unwrap();
+        writeln!(stdin, "{}", call(3, "save_file", serde_json::json!({"path": p("outside/a.figcraft")}))).unwrap();
+        writeln!(stdin, "{}", call(4, "save_file", serde_json::json!({"path": p("out/a.figcraft")}))).unwrap();
+        writeln!(stdin, "{}", call(5, "open_file", serde_json::json!({"path": p("outside/a.figcraft")}))).unwrap();
+        writeln!(stdin, "{}", call(6, "open_file", serde_json::json!({"path": p("out/a.figcraft")}))).unwrap();
+    }
+    drop(child.stdin.take());
+    let out = child.wait_with_output().unwrap();
+    assert!(out.status.success());
+    let lines: Vec<serde_json::Value> = String::from_utf8_lossy(&out.stdout).lines().map(|l| serde_json::from_str(l).unwrap()).collect();
+    assert_eq!(lines.len(), 6);
+    assert!(lines[0]["result"]["instructions"].as_str().unwrap().contains("only these folders may be read"));
+    let error = |i: usize| lines[i]["result"]["isError"] == true;
+    assert!(!error(1) && error(2) && !error(3) && error(4) && !error(5), "{lines:?}");
+    assert!(lines[2]["result"]["content"][0]["text"].as_str().unwrap().contains("automation path rejected"));
+    assert!(d.join("out/a.figcraft").is_file() && !d.join("outside/a.figcraft").exists());
+    let _ = std::fs::remove_dir_all(&d);
+}
+
 #[test]
 fn commands_json_lists_everything() {
     let out = bin().args(["commands", "--json"]).output().unwrap();
     let v: serde_json::Value = serde_json::from_slice(&out.stdout).unwrap();
     assert!(v.as_array().unwrap().len() > 200);
 }
+
+/// The automation roots confine the file subcommands too, not just `mcp` (#833): a read outside a
+/// root, and a write outside a write root, are refused and leave no file behind. Without the flags
+/// the same commands behave as they always did.
+#[test]
+fn file_subcommands_are_confined_to_automation_roots() {
+    let d = tmp("file-roots");
+    let _ = std::fs::remove_dir_all(&d);
+    for sub in ["in", "out"] {
+        std::fs::create_dir_all(d.join(sub)).unwrap();
+    }
+    let p = |rel: &str| d.join(rel).to_string_lossy().into_owned();
+    let out_of = |o: &std::process::Output| String::from_utf8_lossy(&o.stderr).into_owned();
+
+    // A document to work on, made unconfined.
+    std::fs::write(d.join("in/make.json"), br#"[{"command":"shape.rectangle","params":{"x":0,"y":0,"width":40,"height":20}}]"#).unwrap();
+    let made = bin().args(["run", &p("in/make.json"), "--out", &p("in/doc.figcraft")]).output().unwrap();
+    assert!(made.status.success(), "{}", out_of(&made));
+
+    // Inside the roots: renders as usual.
+    let ok = bin()
+        .args(["render", &p("in/doc.figcraft"), "-o", &p("out/ok.png"), "--automation-read-root", &p("in"), "--automation-write-root", &p("out")])
+        .output()
+        .unwrap();
+    assert!(ok.status.success(), "{}", out_of(&ok));
+    assert!(d.join("out/ok.png").is_file());
+
+    // A write outside the write root is refused, and nothing is written.
+    let escaped = d.join("escaped.png");
+    let refused = bin()
+        .args([
+            "render",
+            &p("in/doc.figcraft"),
+            "-o",
+            &escaped.to_string_lossy(),
+            "--automation-read-root",
+            &p("in"),
+            "--automation-write-root",
+            &p("out"),
+        ])
+        .output()
+        .unwrap();
+    assert!(!refused.status.success());
+    assert!(out_of(&refused).contains("may be written"), "{}", out_of(&refused));
+    assert!(!escaped.exists(), "the refused render wrote a file anyway");
+
+    // No write root at all: writing is refused outright, reading still works.
+    let no_write = bin().args(["render", &p("in/doc.figcraft"), "-o", &p("out/no.png"), "--automation-read-root", &p("in")]).output().unwrap();
+    assert!(!no_write.status.success());
+    assert!(out_of(&no_write).contains("no folder may be written"), "{}", out_of(&no_write));
+
+    // A read outside every root is refused: `info` on the document with only `out` readable.
+    let read_refused = bin().args(["info", &p("in/doc.figcraft"), "--automation-read-root", &p("out")]).output().unwrap();
+    assert!(!read_refused.status.success());
+    assert!(out_of(&read_refused).contains("may be read"), "{}", out_of(&read_refused));
+
+    // `convert` and `run` take them as well, and a root that is not a folder is refused.
+    let missing = bin().args(["convert", &p("in/doc.figcraft"), &p("out/c.svg"), "--automation-read-root", &p("missing")]).output().unwrap();
+    assert!(!missing.status.success());
+    assert!(out_of(&missing).contains("automation-read-root"), "{}", out_of(&missing));
+
+    // Unconfined, the same render still writes wherever it is told.
+    let plain = bin().args(["render", &p("in/doc.figcraft"), "-o", &escaped.to_string_lossy()]).output().unwrap();
+    assert!(plain.status.success(), "{}", out_of(&plain));
+    assert!(escaped.is_file());
+    let _ = std::fs::remove_dir_all(&d);
+}
+
+/// An output path that is a symbolic link is written through, to its target, as `std::fs::write`
+/// always did. Routing the CLI's writes through `file_access` for #833 would otherwise have
+/// replaced the link with a regular file, because that write stages the bytes and renames them
+/// into place.
+#[cfg(unix)]
+#[test]
+fn an_unconfined_write_follows_a_symbolic_link() {
+    let d = tmp("symlink-out");
+    let _ = std::fs::remove_dir_all(&d);
+    std::fs::create_dir_all(d.join("real")).unwrap();
+    let p = |rel: &str| d.join(rel).to_string_lossy().into_owned();
+    std::fs::write(d.join("in.json"), br#"[{"command":"shape.rectangle","params":{"x":0,"y":0,"width":40,"height":20}}]"#).unwrap();
+    let made = bin().args(["run", &p("in.json"), "--out", &p("doc.figcraft")]).output().unwrap();
+    assert!(made.status.success(), "{}", String::from_utf8_lossy(&made.stderr));
+
+    let target = d.join("real/target.png");
+    std::fs::write(&target, b"placeholder").unwrap();
+    let link = d.join("link.png");
+    std::os::unix::fs::symlink(&target, &link).unwrap();
+
+    let out = bin().args(["render", &p("doc.figcraft"), "-o", &link.to_string_lossy()]).output().unwrap();
+    assert!(out.status.success(), "{}", String::from_utf8_lossy(&out.stderr));
+    assert!(std::fs::symlink_metadata(&link).unwrap().file_type().is_symlink(), "the link is still a link");
+    let written = std::fs::read(&target).unwrap();
+    assert!(written.starts_with(b"\x89PNG"), "the target holds the render, not the placeholder");
+    let _ = std::fs::remove_dir_all(&d);
+}

apps/figcraft-cli/tests/fonts.rs

@@ -45,3 +45,25 @@ fn headless_runs_resolve_installed_families_unless_opted_out() {
     assert_eq!(run_one("face", face.clone(), &[], false)["family"], json!(installed), "text uses the installed family");
     assert_ne!(run_one("face", face, &["--no-system-fonts"], false)["family"], json!(installed), "opted out, it falls back");
 }
+
+#[test]
+fn info_lists_the_fonts_a_file_uses_that_are_missing() {
+    let d = std::env::temp_dir().join(format!("figcraft-cli-missing-{}", std::process::id()));
+    std::fs::create_dir_all(&d).unwrap();
+    let (script, file) = (d.join("make.json"), d.join("doc.figcraft"));
+    let text =
+        |family: &str| json!({"command": "text.create", "params": {"text": "Hamburgefonstiv", "x": 0, "y": 0, "props": {"fontFamily": family}}});
+    std::fs::write(&script, json!([text("FigCraft Missing CLI"), text("FigCraft Missing CLI")]).to_string()).unwrap();
+    let cli = || Command::new(env!("CARGO_BIN_EXE_figcraft-cli"));
+    let made = cli().arg("run").arg(&script).arg("--out").arg(&file).output().unwrap();
+    assert!(made.status.success(), "{}", String::from_utf8_lossy(&made.stderr));
+
+    let out = cli().arg("info").arg(&file).arg("--json").output().unwrap();
+    assert!(out.status.success(), "{}", String::from_utf8_lossy(&out.stderr));
+    let v: Value = serde_json::from_slice(&out.stdout).unwrap();
+    assert_eq!(v["missingFonts"], json!([{"family": "FigCraft Missing CLI", "layers": 2}]));
+
+    let out = cli().arg("info").arg(&file).output().unwrap();
+    let shown = String::from_utf8_lossy(&out.stdout);
+    assert!(shown.contains("missing font \"FigCraft Missing CLI\": 2 text layers"), "{shown}");
+}

apps/figcraft-server/src/config.rs

@@ -135,9 +135,23 @@ impl Config {
     /// abuse contact, or one whose clients would all count as its proxy).
     pub fn warnings(&self) -> Vec<String> {
         let mut out = Vec::new();
+        let client_max = NetLimits::default().max_server_message >> 20;
+        if usize::try_from(self.file_mb()).is_ok_and(|mb| mb >= client_max) {
+            out.push(format!(
+                "max_file_mb is {}: the app opens files of up to {} MiB, so a file that large can't be opened",
+                self.file_mb(),
+                client_max - 1
+            ));
+        }
         if !self.open_publish {
             return out;
         }
+        if self.file_mb() > 64 {
+            out.push(format!(
+                "open_publish is on with max_file_mb = {}: anyone may send messages that large, and the memory set aside for reading and queueing them grows to eight times it; keep it at 64 or less on a public server",
+                self.file_mb()
+            ));
+        }
         if self.operator_contact.trim().is_empty() {
             out.push("open_publish is on but operator_contact is empty: people can't reach you about abuse; set it (and terms_url)".into());
         }
@@ -168,7 +182,7 @@ impl Config {
             return Err("`idle_days` must be from 0 to 3650".into());
         }
         let terms = self.terms_url.trim();
-        if !terms.is_empty() && !(terms.starts_with("https://") || terms.starts_with("http://")) || terms.contains(char::is_whitespace) {
+        if !(terms.is_empty() || terms.starts_with("https://") || terms.starts_with("http://")) || terms.contains(char::is_whitespace) {
             return Err("`terms_url` must be a web address (https://…)".into());
         }
         if self.operator_contact.chars().count() > 120 || self.operator_contact.chars().any(char::is_control) || terms.len() > 500 {
@@ -253,8 +267,9 @@ impl Config {
         }
     }
 
-    /// Largest message a client may send when open to the public: a whole file (or plugin bundle)
-    /// and a margin, not the core's 64 MiB.
+    /// Largest message a client may send: a whole file (or plugin bundle) and a margin. Open to the
+    /// public this is also the cap (strangers' files stay small); a private server never goes below
+    /// the core's 64 MiB, and a `max_file_mb` above it raises the cap with it.
     fn open_message(&self) -> usize {
         usize::try_from(self.file_mb().max(self.max_plugin_mb).saturating_add(1).saturating_mul(1 << 20)).unwrap_or(usize::MAX)
     }
@@ -265,9 +280,9 @@ impl Config {
     fn core(&self) -> figcraft_collab::Limits {
         let base = figcraft_collab::Limits { max_peers: self.max_people, ..figcraft_collab::Limits::default() };
         if !self.open_publish {
-            return base;
+            return figcraft_collab::Limits { max_message_bytes: base.max_message_bytes.max(self.open_message()), ..base };
         }
-        let max = self.open_message().min(base.max_message_bytes);
+        let max = self.open_message();
         let file = usize::try_from(self.file_mb().saturating_mul(1 << 20)).unwrap_or(usize::MAX);
         figcraft_collab::Limits { max_message_bytes: max, max_log_bytes: (file / 4).max(256 << 10), ..base }
     }
@@ -279,21 +294,24 @@ impl Config {
     pub fn net(&self) -> NetLimits {
         let base = NetLimits { max_connections: self.max_connections, trusted_proxy: self.proxy().ok().flatten(), ..NetLimits::default() };
         if !self.open_publish {
-            return base;
+            let max = base.max_client_message.max(self.open_message());
+            return NetLimits { max_client_message: max, max_queued_bytes: base.max_queued_bytes.max(max.saturating_add(1 << 20)), ..base };
         }
-        let max = self.open_message().min(base.max_client_message);
+        let max = self.open_message();
         // Shared budgets: one block of addresses (an IPv4 address, an IPv6 /48) gets at most an
-        // eighth of each, and its biggest consumers are dropped first.
-        let (queued, reading) = (256usize << 20, 192usize << 20);
+        // eighth of each, and its biggest consumers are dropped first. Each still fits one whole
+        // message, or a file as large as `max_file_mb` could never arrive.
+        let one = max.saturating_add(1 << 20);
+        let (queued, reading) = ((256usize << 20).max(one.saturating_mul(8)), (192usize << 20).max(one.saturating_mul(8)));
         NetLimits {
             max_per_address: self.max_connections_per_ip,
             max_client_message: max,
-            max_queued_bytes: max.saturating_add(1 << 20),
+            max_queued_bytes: one,
             max_queued_block: queued / 8,
             max_queued_total: queued,
-            max_reading_block: max.saturating_add(1 << 20).min(reading / 8),
+            max_reading_block: one.min(reading / 8),
             max_reading_total: reading,
-            max_in_flight: 128 << 20,
+            max_in_flight: (128usize << 20).max(one),
             reserve_for_sessions: self.max_connections / 8,
             request_idle: std::time::Duration::from_secs(20),
             ..base

apps/figcraft-server/src/disk.rs

@@ -8,8 +8,10 @@
 //!   length (u32 LE), CRC-32 (u32 LE), one [`Journal`] entry in the wire encoding.
 //!
 //! Compaction writes the next generation's snapshot, then an empty log of that generation. A log
-//! whose generation isn't the snapshot's is from before a compaction that was cut short: what it
-//! holds is in the snapshot already. A log ends at its first damaged record (a write cut short).
+//! whose generation isn't the snapshot's is usually from before a compaction that was cut short
+//! (what it holds is in the snapshot already), but no checksum covers either generation, so the
+//! store replays such a log anyway and reports any change the snapshot lacked. A log ends at its
+//! first damaged record (a write cut short).
 
 use std::fs::{self, File};
 use std::io::{self, Read, Write};

apps/figcraft-server/src/public_tests.rs

@@ -413,7 +413,7 @@ fn open_mode_has_safe_defaults_and_warns_the_operator() {
     assert_eq!(open.net().request_idle, Duration::from_secs(20), "idle one-shot requests go quickly");
     assert_eq!(open.net().reserve_for_sessions, 512 / 8);
     assert_eq!(open.net().max_client_message, 17 << 20);
-    assert_eq!(private.net().max_client_message, NetLimits::default().max_client_message, "unchanged when private");
+    assert_eq!(private.net().max_client_message, 65 << 20, "private: a 64 MiB file and a margin");
     let w = open.warnings().join("\n");
     assert!(w.contains("operator_contact is empty") && w.contains("trusted_proxy"), "{w}");
     let set = Config { operator_contact: "[email protected]".into(), trusted_proxy: Some("127.0.0.1".into()), max_file_mb: Some(8), ..open };
@@ -493,3 +493,34 @@ fn open_connections_never_reach_what_needs_the_key() {
     assert!(!format!("{info:?}").contains(&k));
     server.stop();
 }
+
+#[test]
+fn files_above_64_mib_fit_every_limit() {
+    // `max_file_mb` may go up to 4096: every cap a whole file's message meets on its way in must
+    // follow it, or the upload is dropped by the transport before the server can say why.
+    for open_publish in [false, true] {
+        let cfg = Config { open_publish, max_file_mb: Some(256), public_url: Some("wss://figcraft.example.com/".into()), ..Config::default() };
+        let (net, core, file) = (cfg.net(), cfg.store().core, 256usize << 20);
+        assert!(net.max_client_message > file, "open={open_publish}: {}", net.max_client_message);
+        assert!(net.max_queued_bytes > file && net.max_reading_block > file && net.max_in_flight > file, "open={open_publish}: {net:?}");
+        assert!(net.max_reading_total >= net.max_reading_block && net.max_queued_total >= net.max_queued_block);
+        assert!(core.max_message_bytes > file, "open={open_publish}: {}", core.max_message_bytes);
+    }
+    // A client takes such a file too, but caps what any server may make it buffer at 1 GiB.
+    assert_eq!(NetLimits::default().max_server_message, 1 << 30);
+}
+
+#[test]
+fn large_files_warn_the_operator() {
+    let public_url = Some("wss://figcraft.example.com/".into());
+    let warns = |open_publish, mb| {
+        Config { open_publish, max_file_mb: Some(mb), public_url: public_url.clone(), ..Config::default() }.warnings().join(
+            "
+",
+        )
+    };
+    assert!(!warns(true, 64).contains("max_file_mb"), "{}", warns(true, 64));
+    assert!(warns(true, 65).contains("open_publish is on with max_file_mb = 65"), "{}", warns(true, 65));
+    assert!(!warns(false, 1023).contains("max_file_mb"), "{}", warns(false, 1023));
+    assert!(warns(false, 1024).contains("can't be opened"), "{}", warns(false, 1024));
+}

apps/figcraft-server/src/store.rs

@@ -440,7 +440,7 @@ impl Store {
             && let Ok(log) = disk::read_log(&bytes)
             && log.generation != generation
         {
-            log::info!("file at {}: its log predates the last compaction; it is ignored", path.display());
+            log::info!("file at {}: its log isn't of its snapshot's generation; it is replayed over it when the file opens", path.display());
         }
         let bytes = [SNAPSHOT, LOG].iter().filter_map(|n| fs::metadata(path.join(n)).ok()).map(|m| m.len()).sum();
         Ok(Entry { meta, links, log: None, bytes, forced: 0 })
@@ -1126,8 +1126,32 @@ impl Store {
                     fresh_log = true;
                 }
             }
-            // From before a compaction that was cut short: the snapshot has it all.
-            Ok(_) => {}
+            // From before a compaction that was cut short, the snapshot has it all; or a generation
+            // field damaged, which no checksum covers. Replaying tells them apart without trusting
+            // it: entries the snapshot holds are skipped, so only edits it lacks change anything.
+            Ok(log) => {
+                let before = server.seq();
+                let mut stopped = None;
+                for entry in log.entries {
+                    if let Err(e) = server.replay(entry) {
+                        stopped = Some(e);
+                        break;
+                    }
+                }
+                let (snap, found, recovered) = (generation, log.generation, server.seq().saturating_sub(before));
+                if recovered > 0 {
+                    issues.push(format!(
+                        "file {file}: its log's generation ({found}) doesn't match its snapshot's ({snap}), but it held \
+                         {recovered} changes the snapshot didn't; they were recovered"
+                    ));
+                }
+                if let Some(e) = stopped {
+                    issues.push(format!(
+                        "file {file}: its log's generation ({found}) doesn't match its snapshot's ({snap}) and it stops \
+                         making sense after {recovered} newer changes ({e}); the rest was dropped"
+                    ));
+                }
+            }
             Err(why) => issues.push(format!("file {file}: {why}; starting a new log")),
         }
         for i in issues {

apps/figcraft-server/tests/header_recovery.rs

@@ -0,0 +1,139 @@
+//! A generation field damaged after an abrupt stop must not make the server drop a log that still
+//! holds confirmed edits (#408): the log is replayed over the snapshot, which only the changes the
+//! snapshot lacks survive, and the damage is reported. A genuine leftover of a compaction cut short
+//! still restores silently.
+#![allow(clippy::unwrap_used, clippy::expect_used, clippy::panic)]
+
+use figcraft_collab::message::{Access, ClientMsg};
+use figcraft_collab::{Client, Outgoing, Replica, Server};
+use figcraft_collab_net::hub::Backend;
+use figcraft_doc::Document;
+use figcraft_server::config::Config;
+use figcraft_server::disk::{self, LOG, SNAPSHOT};
+use figcraft_server::store::{FILES, Store};
+use std::fs;
+use std::path::{Path, PathBuf};
+
+struct Fixture(PathBuf);
+
+impl Fixture {
+    fn new() -> Self {
+        let path = std::env::temp_dir().join(format!("figcraft-header-recovery-{}", figcraft_collab_net::token::file_id().unwrap()));
+        fs::create_dir(&path).unwrap();
+        Self(path)
+    }
+}
+
+impl Drop for Fixture {
+    fn drop(&mut self) {
+        let _ = fs::remove_dir_all(&self.0);
+    }
+}
+
+fn page_name(server: &Server) -> String {
+    let doc = server.document();
+    doc.node(doc.first_page().unwrap()).unwrap().name.clone()
+}
+
+/// A published file whose first page was renamed "Kept", flushed to its log (not compacted), then
+/// the store dropped without stopping (an abrupt stop). Returns the file id and the final state.
+fn renamed_and_stopped(data: &Path) -> (String, Server) {
+    let mut store = Store::open(data, Config::default().store()).unwrap();
+    let snapshot = Replica::new(Document::new("Fixture")).snapshot().unwrap();
+    let (info, _, _) = store.publish("Fixture", &snapshot).unwrap();
+    let id = info.id;
+    let mut server = store.open(&id).unwrap();
+    let ClientMsg::Hello(hello) = Client::hello("f", "", "Editor", "#FF8800") else { panic!("not a hello") };
+    let (_, messages) = server.join_as(hello, Access::Edit).unwrap();
+    let Some(Outgoing::To(_, welcome)) = messages.into_iter().next() else { panic!("no welcome") };
+    let mut client = Client::join(welcome).unwrap();
+    store.changed(&id, &mut server);
+    let mut edited = client.document().clone();
+    let page = edited.first_page().unwrap();
+    edited.node_mut(page).unwrap().name = "Kept".into();
+    let change = client.edit(&edited).unwrap().unwrap();
+    assert!(!server.receive(client.id(), change).is_empty());
+    store.changed(&id, &mut server);
+    assert!(store.flush().is_empty(), "the edit must reach disk");
+    assert_eq!(page_name(&server), "Kept");
+    let dir = data.join(FILES).join(&id);
+    assert!(!disk::read_log(&fs::read(dir.join(LOG)).unwrap()).unwrap().entries.is_empty());
+    assert_eq!(disk::decode_snapshot(&fs::read(dir.join(SNAPSHOT)).unwrap()).unwrap().1.seq, 0, "the rename is only in the log");
+    drop(store);
+    (id, server)
+}
+
+/// Reopen the data directory: the file's first page name and the problems reported.
+fn reopen(data: &Path, id: &str) -> (String, Vec<String>) {
+    let mut store = Store::open(data, Config::default().store()).unwrap();
+    let server = store.open(id).unwrap();
+    (page_name(&server), store.problems().to_vec())
+}
+
+fn flip(path: &Path, at: usize) {
+    let mut bytes = fs::read(path).unwrap();
+    bytes[at] ^= 1;
+    fs::write(path, bytes).unwrap();
+}
+
+/// The generation field's first byte in both headers (after the magic and the format byte).
+const GENERATION_AT: usize = 5;
+
+#[test]
+fn an_intact_log_restores_its_edits_without_a_report() {
+    let fixture = Fixture::new();
+    let (id, _) = renamed_and_stopped(&fixture.0);
+    let (name, problems) = reopen(&fixture.0, &id);
+    assert_eq!(name, "Kept");
+    assert!(problems.is_empty(), "{problems:?}");
+}
+
+#[test]
+fn a_damaged_log_generation_keeps_the_edits_and_is_reported() {
+    let fixture = Fixture::new();
+    let (id, _) = renamed_and_stopped(&fixture.0);
+    let log = fixture.0.join(FILES).join(&id).join(LOG);
+    flip(&log, GENERATION_AT);
+    // The records themselves still read: only the header's generation changed.
+    let read = disk::read_log(&fs::read(&log).unwrap()).unwrap();
+    assert!(read.damaged.is_none() && !read.entries.is_empty());
+    let (name, problems) = reopen(&fixture.0, &id);
+    assert_eq!(name, "Kept", "the flushed rename must survive");
+    assert!(problems.iter().any(|p| p.contains(&id) && p.contains("generation")), "{problems:?}");
+    // And it stays: the recovered edit is now in the file's snapshot.
+    assert_eq!(reopen(&fixture.0, &id).0, "Kept");
+}
+
+#[test]
+fn a_damaged_snapshot_generation_keeps_the_edits_and_is_reported() {
+    let fixture = Fixture::new();
+    let (id, _) = renamed_and_stopped(&fixture.0);
+    let snapshot = fixture.0.join(FILES).join(&id).join(SNAPSHOT);
+    flip(&snapshot, GENERATION_AT);
+    assert!(disk::check_snapshot(&fs::read(&snapshot).unwrap()).is_ok(), "the generation is outside the checksum");
+    let (name, problems) = reopen(&fixture.0, &id);
+    assert_eq!(name, "Kept", "the flushed rename must survive");
+    assert!(problems.iter().any(|p| p.contains(&id) && p.contains("generation")), "{problems:?}");
+    assert_eq!(reopen(&fixture.0, &id).0, "Kept");
+}
+
+#[test]
+fn a_damaged_log_format_is_still_reported() {
+    let fixture = Fixture::new();
+    let (id, _) = renamed_and_stopped(&fixture.0);
+    flip(&fixture.0.join(FILES).join(&id).join(LOG), 4);
+    let (_, problems) = reopen(&fixture.0, &id);
+    assert!(problems.iter().any(|p| p.contains(&id) && p.contains("format")), "{problems:?}");
+}
+
+#[test]
+fn a_log_left_by_a_compaction_cut_short_restores_without_a_report() {
+    let fixture = Fixture::new();
+    let (id, server) = renamed_and_stopped(&fixture.0);
+    // The next snapshot was written (it holds the rename); the old log wasn't replaced yet.
+    let bytes = disk::encode_snapshot(2, &server.state().unwrap()).unwrap();
+    fs::write(fixture.0.join(FILES).join(&id).join(SNAPSHOT), bytes).unwrap();
+    let (name, problems) = reopen(&fixture.0, &id);
+    assert_eq!(name, "Kept");
+    assert!(problems.is_empty(), "a leftover log is expected, not damage: {problems:?}");
+}

apps/figcraft-web/Cargo.toml

@@ -26,4 +26,4 @@ eframe = { workspace = true, features = ["default_fonts", "wgpu", "accesskit"] }
 wasm-bindgen = "0.2"
 js-sys = "0.3"
 wasm-bindgen-futures = "0.4"
-web-sys = { version = "0.3", features = ["Window", "Document", "Element", "HtmlCanvasElement", "HtmlElement", "HtmlAnchorElement", "Node", "Blob", "BlobPropertyBag", "Url", "Location", "MediaQueryList", "Navigator", "Gamepad", "GamepadButton", "GamepadMappingType"] }
+web-sys = { version = "0.3", features = ["Window", "Document", "Element", "HtmlCanvasElement", "HtmlElement", "HtmlAnchorElement", "Node", "Blob", "BlobPropertyBag", "File", "FileList", "HtmlInputElement", "EventTarget", "Url", "Location", "MediaQueryList", "Navigator", "Gamepad", "GamepadButton", "GamepadMappingType"] }

apps/figcraft-web/src/main.rs

@@ -14,7 +14,16 @@
 //!   join from other machines.
 //!
 //! URL query flag: `?webgl` forces the WebGL2 backend instead of WebGPU.
+//!
+//! URL fragment: `#join=<invite link or join code>` joins that live session once the page has
+//! loaded, so a bookmark opens a shared file. `join` takes the rest of the fragment: put it last.
+//! The link carries the session's secret; a fragment is never sent to the web host, but the address
+//! bar and the browser history keep it, so the URL is as private as the link itself.
 
+#[cfg(any(target_arch = "wasm32", test))]
+mod query;
+#[cfg(test)]
+mod query_tests;
 #[cfg(target_arch = "wasm32")]
 mod web;
 

apps/figcraft-web/src/query.rs

@@ -0,0 +1,15 @@
+//! The page's URL: the invite link its fragment names.
+
+/// The invite link in `#join=<link>` (`fragment` is `location.hash`, with or without its `#`), still
+/// escaped. The fragment, unlike the query, never leaves the browser, so the link's secret stays out
+/// of the web host's logs and `Referer` headers. `join` takes the rest of the fragment, so a pasted
+/// `figcraft://join?host=…&file=…&token=…` keeps its own `&`s. Anything longer than an escaped invite
+/// link can be is ignored; what is left is checked by `collab.join` like a link the desktop app is
+/// opened with.
+pub fn join_link(fragment: &str) -> Option<&str> {
+    // An invite link is at most 2 KiB; every byte of it escaped is three.
+    const MAX: usize = 3 * 2048;
+    let fragment = fragment.strip_prefix('#').unwrap_or(fragment);
+    let start = if fragment.starts_with("join=") { 0 } else { fragment.find("&join=")? + 1 };
+    fragment.get(start + "join=".len()..).filter(|link| !link.is_empty() && link.len() <= MAX)
+}

apps/figcraft-web/src/query_tests.rs

@@ -0,0 +1,29 @@
+//! `#join=` in the page's URL.
+
+use crate::query::join_link;
+
+#[test]
+fn join_takes_the_rest_of_the_fragment() {
+    let link = "figcraft://join?host=192.168.1.20:47900&file=abc&token=AbCdEfGhIjKlMnOpQrStUv";
+    assert_eq!(join_link(&format!("#join={link}")), Some(link), "a pasted link keeps its own &s");
+    assert_eq!(join_link(&format!("#x=1&join={link}")), Some(link), "after other entries");
+    assert_eq!(join_link("#join=figcraft%3A%2F%2Fjoin%3Fhost%3Dh"), Some("figcraft%3A%2F%2Fjoin%3Fhost%3Dh"), "escaped, decoded later");
+    assert_eq!(join_link("join=K7M-2QX-9TD"), Some("K7M-2QX-9TD"), "a join code, no leading #");
+}
+
+#[test]
+fn no_join_without_the_entry() {
+    assert_eq!(join_link(""), None);
+    assert_eq!(join_link("#"), None);
+    assert_eq!(join_link("#join="), None);
+    assert_eq!(join_link("#rejoin=x"), None, "only the whole entry name");
+    assert_eq!(join_link("#xjoin=x&a=1"), None);
+    assert_eq!(join_link("?join=x"), None, "the query isn't read: it goes to the web host");
+}
+
+#[test]
+fn an_overlong_link_is_ignored() {
+    let long = format!("#join=figcraft://join?host=h&file=f&token={}", "a".repeat(7000));
+    assert_eq!(join_link(&long), None);
+    assert_eq!(join_link(&format!("#join={}", "é".repeat(4000))), None, "length counts bytes");
+}

apps/figcraft-web/src/web.rs

@@ -1,7 +1,7 @@
 //! The browser shell: web `Services` and the eframe web runner.
 
 use figcraft_engine::Session;
-use figcraft_ui_egui::{FigApp, Services};
+use figcraft_ui_egui::{ContentsFuture, FigApp, Services};
 use wasm_bindgen::JsCast as _;
 
 const CANVAS_ID: &str = "figcraft_canvas";
@@ -40,7 +40,13 @@ pub fn start() {
                     // on the socket wakes the page for a frame.
                     let ctx = cc.egui_ctx.clone();
                     session.live.install(Box::new(figcraft_collab_net::NetLink::new(std::sync::Arc::new(move || ctx.request_repaint()))));
-                    let fig = FigApp::new(session, Box::new(WebServices { reduce_motion, ctx: cc.egui_ctx.clone() }));
+                    let mut fig = FigApp::new(session, Box::new(WebServices { reduce_motion, ctx: cc.egui_ctx.clone() }));
+                    // `#join=<link>`: join that session, as opening an invite link does on the desktop.
+                    let hash = web_sys::window().and_then(|w| w.location().hash().ok()).unwrap_or_default();
+                    if let Some(link) = crate::query::join_link(&hash) {
+                        let link = js_sys::decode_uri_component(link).ok().and_then(|s| s.as_string()).unwrap_or_else(|| link.to_string());
+                        figcraft_ui_egui::live::open_invite(&mut fig, &link);
+                    }
                     Ok(Box::new(WebShell { fig }))
                 }),
             )
@@ -69,9 +75,10 @@ impl eframe::App for WebShell {
     }
 }
 
-/// Browser services. Open dialogs return nothing for now (the trait's defaults); files are saved
-/// as downloads. Copies go to the system clipboard through egui's output; pastes arrive as paste
-/// events with their text (a page can't read the clipboard when it likes).
+/// Browser services. Files are opened and imported through the browser's file picker, which hands
+/// over their contents (pickers that need a path return nothing, the trait's defaults); files are
+/// saved as downloads. Copies go to the system clipboard through egui's output; pastes arrive as
+/// paste events with their text (a page can't read the clipboard when it likes).
 struct WebServices {
     /// `prefers-reduced-motion: reduce` (it follows the setting while the page is open).
     reduce_motion: Option<web_sys::MediaQueryList>,
@@ -79,6 +86,16 @@ struct WebServices {
 }
 
 impl Services for WebServices {
+    /// An `<input type="file">` taking `exts`, clicked; its file is read once picked.
+    fn pick_open_contents(&mut self, _title: &str, exts: &[&str]) -> Option<ContentsFuture> {
+        let accept = exts.iter().map(|e| format!(".{e}")).collect::<Vec<_>>().join(",");
+        Some(Box::pin(async move {
+            pick_file(&accept).await.unwrap_or_else(|e| {
+                log::error!("couldn't open a file: {e:?}");
+                None
+            })
+        }))
+    }
     fn downloads(&self) -> bool {
         true
     }
@@ -130,6 +147,90 @@ impl Services for WebServices {
     }
 }
 
+/// The file picked in the browser's file picker (`accept`: the extensions it offers), with its
+/// name; `None` when the picker is cancelled, `Some(Err)` with what to tell the user when the file
+/// can't be read.
+async fn pick_file(accept: &str) -> Result<Option<Result<(String, Vec<u8>), String>>, wasm_bindgen::JsValue> {
+    let window = web_sys::window().ok_or("no window")?;
+    let document = window.document().ok_or("no document")?;
+    let body = document.body().ok_or("no body")?;
+    let input: web_sys::HtmlInputElement = document.create_element("input")?.dyn_into()?;
+    input.set_type("file");
+    input.set_accept(accept);
+    input.set_hidden(true);
+    // Some browsers (older Safari) open the picker only for an input in the page.
+    body.append_child(&input)?;
+    let (closed, picker) = PickerClosed::new(&window, input.clone());
+    input.click();
+    let result = wasm_bindgen_futures::JsFuture::from(closed).await;
+    let file = input.files().and_then(|files| files.get(0));
+    drop(picker);
+    result?;
+    let Some(file) = file else { return Ok(None) };
+    let name = file.name();
+    if let Err(why) = figcraft_ui_egui::browser_can_read(&name, file.size()) {
+        return Ok(Some(Err(why)));
+    }
+    Ok(Some(match wasm_bindgen_futures::JsFuture::from(file.array_buffer()).await {
+        Ok(buffer) => Ok((name, js_sys::Uint8Array::new(&buffer).to_vec())),
+        Err(e) => {
+            log::error!("couldn't read {name}: {e:?}");
+            Err(figcraft_ui_egui::unreadable(&name))
+        }
+    }))
+}
+
+/// How long after the page gets focus back the file picker counts as closed (milliseconds): a
+/// picked file's `change` can come just after the focus, and must win. A `change` later than this
+/// (a slow cloud-backed file in a browser that never sends `cancel`) counts as a cancel.
+const PICKER_FOCUS_SETTLE_MS: i32 = 1_000;
+
+/// Settles a file picker's promise once: on `change` (a file was picked), on `cancel` (closed
+/// without one) or shortly after the page gets focus back, for browsers that never send `cancel`
+/// (Safari before 16.4), where the pick would otherwise stay pending and block every later one.
+/// Dropping it (also when the pick is abandoned) removes the input, the focus listener and its timer.
+struct PickerClosed {
+    window: web_sys::Window,
+    input: web_sys::HtmlInputElement,
+    _settle: wasm_bindgen::closure::Closure<dyn FnMut()>,
+    on_focus: wasm_bindgen::closure::Closure<dyn FnMut()>,
+    timer: std::rc::Rc<std::cell::Cell<Option<i32>>>,
+}
+
+impl PickerClosed {
+    fn new(window: &web_sys::Window, input: web_sys::HtmlInputElement) -> (js_sys::Promise, Self) {
+        let resolve = std::rc::Rc::new(std::cell::RefCell::new(None::<js_sys::Function>));
+        let slot = resolve.clone();
+        let closed = js_sys::Promise::new(&mut |res, _rej| *slot.borrow_mut() = Some(res));
+        let settle = wasm_bindgen::closure::Closure::<dyn FnMut()>::new(move || {
+            if let Some(res) = resolve.borrow_mut().take() {
+                let _ = res.call0(&wasm_bindgen::JsValue::NULL);
+            }
+        });
+        let _ = input.add_event_listener_with_callback("change", settle.as_ref().unchecked_ref());
+        let _ = input.add_event_listener_with_callback("cancel", settle.as_ref().unchecked_ref());
+        let timer = std::rc::Rc::new(std::cell::Cell::new(None));
+        let (w, t, f) = (window.clone(), timer.clone(), settle.as_ref().unchecked_ref::<js_sys::Function>().clone());
+        let on_focus = wasm_bindgen::closure::Closure::<dyn FnMut()>::new(move || {
+            if t.get().is_none() {
+                t.set(w.set_timeout_with_callback_and_timeout_and_arguments_0(&f, PICKER_FOCUS_SETTLE_MS).ok());
+            }
+        });
+        let _ = window.add_event_listener_with_callback("focus", on_focus.as_ref().unchecked_ref());
+        (closed, Self { window: window.clone(), input, _settle: settle, on_focus, timer })
+    }
+}
+
+impl Drop for PickerClosed {
+    fn drop(&mut self) {
+        if let Some(t) = self.timer.take() {
+            self.window.clear_timeout_with_handle(t);
+        }
+        let _ = self.window.remove_event_listener_with_callback("focus", self.on_focus.as_ref().unchecked_ref());
+        self.input.remove();
+    }
+}
+
 fn download(name: &str, bytes: &[u8]) -> Result<(), wasm_bindgen::JsValue> {
     let window = web_sys::window().ok_or("no window")?;
     let document = window.document().ok_or("no document")?;

apps/figcraft/Cargo.toml

@@ -43,3 +43,9 @@ wat = { workspace = true }
 
 [build-dependencies]
 winresource = "0.1"
+
+[target.'cfg(target_os = "linux")'.dependencies]
+# Use vector window controls without a title-font renderer or embedded Cantarell.
+winit = { version = "0.30", default-features = false, features = ["wayland-csd-adwaita-notitle"] }
+raw-window-handle = "0.6"
+wayland-client = "0.31"

apps/figcraft/src/args.rs

@@ -1,7 +1,10 @@
-//! The command line: `figcraft [--control <port>] [files…] [figcraft://join?…]`. An invite link
+//! The command line: `figcraft [--control <port>] [--automation-read-root <dir>]…
+//! [--automation-write-root <dir>]… [files…] [figcraft://join?…]`. An invite link
 //! (what the system passes when a `figcraft://` link is opened) joins that session once the window
 //! is up; everything else that isn't a flag is a file to open, as a path or a `file://` URL (the
-//! Linux desktop entry passes URLs, `%U`, so that it can also hand over invite links).
+//! Linux desktop entry passes URLs, `%U`, so that it can also hand over invite links). Any other
+//! `--flag` is unknown and stops the app at startup (#836): a mistyped root flag must never leave
+//! the app running unconfined. After a bare `--`, every argument is a file.
 
 /// What the app was started with.
 #[derive(Debug, Default, PartialEq, Eq)]
@@ -11,6 +14,13 @@ pub struct Args {
     pub files: Vec<String>,
     /// The last invite link given.
     pub join: Option<String>,
+    /// `--automation-read-root <dir>` / `--automation-write-root <dir>` (each repeatable; `=` works
+    /// too): the folders the app's file access is confined to. A flag without a value gives `""`,
+    /// which is refused at startup.
+    pub read_roots: Vec<String>,
+    pub write_roots: Vec<String>,
+    /// `--flags` the app doesn't know, as given.
+    pub unknown: Vec<String>,
 }
 
 /// An invite link rather than a file (`figcraft:` links, in any case).
@@ -49,13 +59,27 @@ pub fn parse(args: &[String]) -> Args {
     let mut out = Args::default();
     let mut it = args.iter();
     while let Some(a) = it.next() {
-        if a == "--control" {
+        if a == "--" {
+            out.files.extend(it.by_ref().cloned());
+            break;
+        }
+        let (flag, inline) = a.split_once('=').map_or((a.as_str(), None), |(f, v)| (f, Some(v.to_string())));
+        let roots = match flag {
+            "--automation-read-root" => Some(&mut out.read_roots),
+            "--automation-write-root" => Some(&mut out.write_roots),
+            _ => None,
+        };
+        if let Some(roots) = roots {
+            roots.push(inline.or_else(|| it.next().cloned()).unwrap_or_default());
+        } else if a == "--control" {
             out.control = it.next().and_then(|p| p.parse().ok());
         } else if is_invite(a) {
             out.join = Some(a.clone());
         } else if let Some(path) = file_url_path(a) {
             out.files.push(path);
-        } else if !a.starts_with("--") {
+        } else if a.starts_with("--") {
+            out.unknown.push(a.clone());
+        } else {
             out.files.push(a.clone());
         }
     }

apps/figcraft/src/args_tests.rs

@@ -9,13 +9,36 @@ fn args(a: &[&str]) -> Vec<String> {
 #[test]
 fn files_and_the_control_port() {
     assert_eq!(parse(&args(&[])), Args::default());
-    let a = parse(&args(&["--control", "4242", "a.figcraft", "--verbose", "b.svg"]));
-    assert_eq!(a, Args { control: Some(4242), files: args(&["a.figcraft", "b.svg"]), join: None });
+    let a = parse(&args(&["--control", "4242", "a.figcraft", "b.svg"]));
+    assert_eq!(a, Args { control: Some(4242), files: args(&["a.figcraft", "b.svg"]), ..Args::default() });
     // A missing or bad port is ignored, not taken as a file.
     assert_eq!(parse(&args(&["--control"])), Args::default());
     assert_eq!(parse(&args(&["--control", "nope"])).control, None);
 }
 
+#[test]
+fn automation_roots_repeat_and_are_never_files() {
+    let a = parse(&args(&["--automation-read-root", "in", "--automation-write-root=out", "--automation-read-root=more", "a.figcraft"]));
+    assert_eq!(a.read_roots, args(&["in", "more"]));
+    assert_eq!(a.write_roots, args(&["out"]));
+    assert_eq!(a.files, args(&["a.figcraft"]));
+    // A flag without its folder is kept as an empty one, which startup refuses.
+    assert_eq!(parse(&args(&["--automation-write-root"])).write_roots, args(&[""]));
+}
+
+#[test]
+fn unknown_flags_are_refused_never_ignored() {
+    // #836: a mistyped root flag (or one an older release lacks) must stop the app, not start it
+    // unconfined. Both forms, with and without `=`.
+    let a = parse(&args(&["--automation-write-roots", "out", "--automation-write-dir=out", "--verbose", "a.figcraft"]));
+    assert_eq!(a.unknown, args(&["--automation-write-roots", "--automation-write-dir=out", "--verbose"]));
+    assert!(a.write_roots.is_empty());
+    // Single-dash arguments are left as they were (files); after `--` everything is a file.
+    let a = parse(&args(&["--control", "1", "--", "--odd.figcraft", "--automation-write-root=x"]));
+    assert_eq!(a.files, args(&["--odd.figcraft", "--automation-write-root=x"]));
+    assert!(a.unknown.is_empty() && a.write_roots.is_empty());
+}
+
 #[test]
 fn invite_links_join_instead_of_opening() {
     let link = "figcraft://join?host=192.168.1.20:47900&file=abc&token=AbCdEfGhIjKlMnOpQrStUv";

apps/figcraft/src/control_server_tests.rs

@@ -160,7 +160,11 @@ fn connection_limit_rejects_excess_clients_and_reuses_finished_slots() {
     assert_eq!(workers.len(), 1);
     client.write_all(b"invalid\n").unwrap();
     assert_eq!(reply(&mut BufReader::new(client.try_clone().unwrap()))["ok"], false);
-    client.shutdown(Shutdown::Both).unwrap();
+    // The server closes this connection after answering an invalid request, and shutting down
+    // a socket whose peer has already closed is ENOTCONN on macOS and the BSDs where Linux
+    // returns Ok. Closing the client is what the worker is waiting for, so the result is moot:
+    // the other shutdowns in this file run while the peer is still open and stay checked.
+    let _ = client.shutdown(Shutdown::Both);
     workers.pop().unwrap().join().unwrap();
 }
 

apps/figcraft/src/linux_window.rs

@@ -0,0 +1,112 @@
+//! Request winit's frame only on Wayland compositors without xdg-decoration.
+//! Desktop/session names cannot identify the backend of an individual window.
+
+use std::os::unix::net::UnixStream;
+use std::path::PathBuf;
+use std::sync::mpsc;
+use std::time::Duration;
+
+use raw_window_handle::{HasDisplayHandle, RawDisplayHandle};
+use wayland_client::globals::{GlobalListContents, registry_queue_init};
+use wayland_client::protocol::wl_registry;
+use wayland_client::{Connection, Dispatch, QueueHandle};
+
+/// Capture the socket path before winit consumes an inherited WAYLAND_SOCKET.
+/// Never consume, duplicate or query that inherited connection: there may be no
+/// independently addressable display, or WAYLAND_DISPLAY may name another server.
+pub fn display_socket() -> Option<PathBuf> {
+    if std::env::var_os("WAYLAND_SOCKET").is_some_and(|s| !s.is_empty()) {
+        return None;
+    }
+    let display = std::env::var_os("WAYLAND_DISPLAY").filter(|s| !s.is_empty())?;
+    let path = PathBuf::from(display);
+    if path.is_absolute() {
+        Some(path)
+    } else {
+        std::env::var_os("XDG_RUNTIME_DIR").filter(|s| !s.is_empty()).map(|dir| PathBuf::from(dir).join(path))
+    }
+}
+
+pub fn needs_native_frame(cc: &eframe::CreationContext<'_>, socket: Option<PathBuf>) -> bool {
+    let wayland = cc.display_handle().is_ok_and(|h| matches!(h.as_raw(), RawDisplayHandle::Wayland(_)));
+    if !wayland {
+        log::debug!("window controls: non-Wayland window, retaining custom controls");
+        return false;
+    }
+    let server_decorations = socket.and_then(probe);
+    log::debug!("window controls: Wayland xdg-decoration available: {server_decorations:?}");
+    native_frame(wayland, server_decorations)
+}
+
+fn native_frame(wayland: bool, server_decorations: Option<bool>) -> bool {
+    wayland && server_decorations == Some(false)
+}
+
+fn probe(socket: PathBuf) -> Option<bool> {
+    // The compositor must not be able to block startup on a registry roundtrip.
+    // On failure/timeout retain FigCraft's own working title bar and buttons.
+    let (send, receive) = mpsc::sync_channel(1);
+    std::thread::Builder::new()
+        .name("wayland-decorations".into())
+        .spawn(move || {
+            let _ = send.send(registry_has_decorations(socket));
+        })
+        .ok()?;
+    receive.recv_timeout(Duration::from_millis(500)).ok().flatten()
+}
+
+fn registry_has_decorations(socket: PathBuf) -> Option<bool> {
+    // A fresh connection leaves winit's event queue and inherited descriptors alone.
+    let stream = UnixStream::connect(socket).ok()?;
+    let connection = Connection::from_socket(stream).ok()?;
+    let (globals, _queue) = registry_queue_init::<Registry>(&connection).ok()?;
+    Some(globals.contents().with_list(|list| list.iter().any(|g| g.interface == "zxdg_decoration_manager_v1")))
+}
+
+struct Registry;
+
+impl Dispatch<wl_registry::WlRegistry, GlobalListContents> for Registry {
+    fn event(
+        _state: &mut Self,
+        _registry: &wl_registry::WlRegistry,
+        _event: wl_registry::Event,
+        _data: &GlobalListContents,
+        _connection: &Connection,
+        _queue: &QueueHandle<Self>,
+    ) {
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn only_wayland_without_server_decorations_uses_the_frame() {
+        for (wayland, server_decorations, expected) in [
+            (false, None, false),
+            (false, Some(false), false),
+            (false, Some(true), false),
+            (true, Some(true), false),
+            (true, Some(false), true),
+            (true, None, false),
+        ] {
+            assert_eq!(super::native_frame(wayland, server_decorations), expected);
+        }
+    }
+
+    #[test]
+    fn an_unavailable_display_keeps_the_custom_controls() {
+        assert_eq!(super::probe("/nonexistent/figcraft-wayland-test".into()), None);
+    }
+
+    #[test]
+    fn an_unresponsive_display_cannot_block_window_startup() -> std::io::Result<()> {
+        let socket = std::env::temp_dir().join(format!("figcraft-decoration-timeout-{}", std::process::id()));
+        let listener = std::os::unix::net::UnixListener::bind(&socket)?;
+        let start = std::time::Instant::now();
+        assert_eq!(super::probe(socket.clone()), None);
+        assert!(start.elapsed() < std::time::Duration::from_secs(2));
+        drop(listener);
+        let _ = std::fs::remove_file(socket);
+        Ok(())
+    }
+}

apps/figcraft/src/main.rs

@@ -6,6 +6,12 @@
 //! `--control <port>` (or `FIGCRAFT_CONTROL_PORT`) starts a localhost JSON-lines control server:
 //! `{"id":1,"method":"engine.execute","params":{"command":"shape.rectangle","params":{"x":0,"y":0,"width":100,"height":100}}}`
 //! → `{"id":1,"ok":true,"result":{…}}`. Methods: `figcraft_ui_egui::control`.
+//!
+//! `--automation-read-root <dir>` / `--automation-write-root <dir>` (each repeatable) confine the
+//! files the window and the control channel read and write (`figcraft_engine::file_access`); the
+//! app's own folders (settings, recovery copies, installed plugins) and opening the files given on
+//! the command line are not. A root that isn't an existing folder stops the app at startup, and so
+//! does any flag the app doesn't know (a mistyped root flag must not start the app unconfined).
 #![deny(clippy::unwrap_used, clippy::expect_used, clippy::panic, clippy::unimplemented, clippy::todo, clippy::unreachable)]
 #![cfg_attr(all(target_os = "windows", not(debug_assertions)), windows_subsystem = "windows")]
 
@@ -15,6 +21,8 @@ mod args;
 mod control_server;
 mod gamepad;
 mod graphics;
+#[cfg(target_os = "linux")]
+mod linux_window;
 mod recovery;
 mod services;
 mod startup;
@@ -100,10 +108,13 @@ impl eframe::App for App {
     }
 
     fn on_exit(&mut self) {
-        with_app(|fig| services::save_state(fig));
-        if let Some(r) = recovery::lock(&self.recovery).take() {
-            r.finish();
-        }
+        // With the app out of reach (busy), its recovery copies stay for the next start.
+        let copies = recovery::lock(&self.recovery).take();
+        with_app(|fig| services::shutdown(fig, services::config_dir().as_deref(), copies));
+        // Everything is kept: end before the windows' teardown, where AppKit's Touch Bar support
+        // throws on the content view AccessKit restores (craft-libs#3, #781).
+        #[cfg(target_os = "macos")]
+        std::process::exit(0);
     }
 }
 
@@ -119,6 +130,23 @@ fn main() -> eframe::Result {
         return Ok(());
     }
     let args = args::parse(&args);
+    if let Some(flag) = args.unknown.first() {
+        eprintln!(
+            "FigCraft: unknown option {flag}\nUsage: figcraft [--control PORT] [--automation-read-root DIR]... [--automation-write-root DIR]... [FILE | figcraft://join?...]..."
+        );
+        std::process::exit(2);
+    }
+    let roots = match (
+        args.read_roots.is_empty() && args.write_roots.is_empty(),
+        figcraft_engine::file_access::Roots::new(&args.read_roots, &args.write_roots),
+    ) {
+        (true, _) => None,
+        (false, Ok(r)) => Some(Arc::new(r)),
+        (false, Err(e)) => {
+            eprintln!("FigCraft: {e}");
+            std::process::exit(2);
+        }
+    };
     let port = args.control.or_else(|| std::env::var("FIGCRAFT_CONTROL_PORT").ok().and_then(|p| p.parse().ok()));
     // System fonts: index them in the background, then wake the UI (an idle window draws no frames)
     // to lay text out again with them.
@@ -143,6 +171,7 @@ fn main() -> eframe::Result {
             log::error!("{f}: {e}");
         }
     }
+    let opened: Vec<u64> = session.docs.iter().map(|d| d.uid).collect();
     // Documents a crashed or killed run left unsaved come back; this run keeps its own copies.
     let recovery_root = services::config_dir().map(|d| d.join("Recovery"));
     // The preferences first: they hold the online files a recovered document may be one of.
@@ -174,7 +203,10 @@ fn main() -> eframe::Result {
     // open (no frame then).
     figcraft_ui_egui::i18n::set(&session.prefs.language, figcraft_ui_egui::Services::system_language(&svc).as_deref());
     let mut fig = FigApp::new(session, Box::new(svc));
+    fig.automation_roots = roots;
     fig.ui.home = false;
+    // Files named on the command line are the user's too: their missing fonts are listed.
+    fig.ui.font_checks = opened;
     fig.note_recovered(recovered.copies);
     if let Some(link) = &args.join {
         figcraft_ui_egui::live::open_invite(&mut fig, link);
@@ -192,21 +224,18 @@ fn main() -> eframe::Result {
         .with_inner_size([1440.0, 900.0])
         .with_min_inner_size([800.0, 500.0])
         .with_drag_and_drop(true);
-    // The tab strip is the title bar: macOS keeps its window buttons inset into it; elsewhere the
-    // window is frameless and FigCraft draws the buttons and resize edges.
-    if cfg!(target_os = "macos") {
-        viewport = viewport.with_fullsize_content_view(true).with_titlebar_shown(false).with_title_shown(false);
-        fig.ui.title_bar = figcraft_ui_egui::TitleBar::Inset;
-    } else {
-        viewport = viewport.with_decorations(false);
-        fig.ui.title_bar = figcraft_ui_egui::TitleBar::Custom;
-    }
+    // Start frameless on Linux; the app creator checks the actual display backend
+    // before enabling a client-side frame. Other windows inherit that decision.
+    fig.ui.title_bar = desktop_title_bar();
+    viewport = window_chrome(viewport, fig.ui.title_bar);
     if let Some(icon) = icon {
         viewport = viewport.with_icon(icon);
     }
     let mut options = eframe::NativeOptions { viewport, renderer: eframe::Renderer::Wgpu, ..Default::default() };
     graphics::configure(&mut options.wgpu_options);
     figcraft_ui_egui::windows::install(fig);
+    #[cfg(target_os = "linux")]
+    let linux_display = linux_window::display_socket();
     // Registered before the event loop starts, so it catches the Finder event that launched the app
     // as well as later ones. Lives until the event loop returns; the app creator only borrows it.
     #[cfg(target_os = "macos")]
@@ -217,6 +246,11 @@ fn main() -> eframe::Result {
         "FigCraft",
         options,
         Box::new(move |_cc| {
+            #[cfg(target_os = "linux")]
+            if linux_window::needs_native_frame(_cc, linux_display) {
+                let _ = with_app(|fig| fig.ui.title_bar = figcraft_ui_egui::TitleBar::Native);
+                _cc.egui_ctx.send_viewport_cmd(egui::ViewportCommand::Decorations(true));
+            }
             Ok(Box::new(App {
                 queue,
                 ctx_slot,
@@ -233,3 +267,28 @@ fn main() -> eframe::Result {
     }
     result
 }
+
+fn desktop_title_bar() -> figcraft_ui_egui::TitleBar {
+    use figcraft_ui_egui::TitleBar;
+    if cfg!(target_os = "macos") { TitleBar::Inset } else { TitleBar::Custom }
+}
+
+fn window_chrome(viewport: egui::ViewportBuilder, title_bar: figcraft_ui_egui::TitleBar) -> egui::ViewportBuilder {
+    use figcraft_ui_egui::TitleBar;
+    match title_bar {
+        TitleBar::Inset => viewport.with_fullsize_content_view(true).with_titlebar_shown(false).with_title_shown(false),
+        TitleBar::Native => viewport.with_decorations(true),
+        TitleBar::Custom => viewport.with_decorations(false),
+    }
+}
+
+#[cfg(all(test, target_os = "linux"))]
+mod linux_window_tests {
+    #[test]
+    fn linux_starts_with_the_existing_frameless_title_bar() {
+        let bar = super::desktop_title_bar();
+        assert_eq!(bar, figcraft_ui_egui::TitleBar::Custom);
+        let viewport = super::window_chrome(egui::ViewportBuilder::default(), bar);
+        assert_eq!(viewport.decorations, Some(false));
+    }
+}

apps/figcraft/src/recovery.rs

@@ -120,8 +120,7 @@ impl Recovery {
         (0..10).find_map(|n| {
             let dir = root.join(if n == 0 { pid.to_string() } else { format!("{pid}-{n}") });
             std::fs::create_dir_all(&dir).ok()?;
-            let lock = File::options().write(true).create(true).truncate(false).open(dir.join(LOCK)).ok()?;
-            lock.try_lock().ok()?;
+            let lock = lock_folder(&dir).ok()?;
             Some(Self { dir, _lock: lock, written: HashMap::new(), next: 0.0, waiting: Vec::new() })
         })
     }
@@ -250,6 +249,17 @@ impl Recovery {
         self.written.insert(uid, Copy { done: None, flight: Some((vec![revision], writer)) });
     }
 
+    /// Quitting: a normal quit ([`finish`](Self::finish)) when the unsaved-changes question was
+    /// `asked` or nothing is unsaved. Otherwise (macOS's Quit menu ends the app without asking) the
+    /// unsaved documents are copied and the copies stay for the next start, as after a crash.
+    pub fn quit(mut self, s: &Session, asked: bool) {
+        if asked || !s.docs.iter().any(|d| needs_copy(s, d)) {
+            return self.finish();
+        }
+        self.write(s, true);
+        self.settle(s);
+    }
+
     /// A normal quit: the documents were saved or their changes discarded on purpose. (Earlier
     /// runs' copies still waiting for their outcome stay for the next start.)
     pub fn finish(self) {
@@ -282,6 +292,17 @@ fn remove_kept(w: Waiting) {
 /// The extension of the note beside the copy of a document that is one of your online files.
 const ONLINE: &str = "online";
 
+/// How long the startup waits, once, for folder locks that may free themselves (#334).
+#[cfg(unix)]
+const LOCK_WAIT: std::time::Duration = std::time::Duration::from_millis(100);
+
+/// Lock the folder `dir` (`WouldBlock` while another process holds it).
+fn lock_folder(dir: &Path) -> Result<File, std::fs::TryLockError> {
+    let lock = File::options().write(true).create(true).truncate(false).open(dir.join(LOCK)).map_err(std::fs::TryLockError::Error)?;
+    lock.try_lock()?;
+    Ok(lock)
+}
+
 /// The copy at `file` is of one of your online files: join that file again as its owner, keeping
 /// the copy to compare with what arrives. The session, or `None` when the copy isn't one (or its
 /// file isn't recorded any more, or is open already): then it opens as any other copy.
@@ -351,6 +372,7 @@ pub fn recover_all(root: &Path, s: &mut Session) -> Recovered {
             }
         }
     };
+    let (mut free, mut held) = (Vec::new(), Vec::new());
     for e in entries.flatten() {
         let path = e.path();
         if !path.is_dir() {
@@ -358,10 +380,22 @@ pub fn recover_all(root: &Path, s: &mut Session) -> Recovered {
             continue;
         }
         // Still running (another window of the app), or not ours to take.
-        let Ok(lock) = File::options().write(true).create(true).truncate(false).open(path.join(LOCK)) else { continue };
-        if lock.try_lock().is_err() {
-            continue;
+        match lock_folder(&path) {
+            Ok(lock) => free.push((path, lock)),
+            Err(std::fs::TryLockError::WouldBlock) => held.push(path),
+            Err(_) => {}
         }
+    }
+    // A child between its `fork` and its `exec` shares the run's open descriptors, and a `flock`
+    // lasts while any of them is open, so an ended run's folder can look held for a moment. Wait
+    // once, however many folders are held, and try those again (#334). Windows doesn't pass the
+    // lock to child processes.
+    #[cfg(unix)]
+    if !held.is_empty() {
+        std::thread::sleep(LOCK_WAIT);
+        free.extend(held.into_iter().filter_map(|path| lock_folder(&path).ok().map(|lock| (path, lock))));
+    }
+    for (path, lock) in free {
         let lock = Arc::new(lock);
         let files: Vec<PathBuf> = std::fs::read_dir(&path).into_iter().flatten().flatten().map(|f| f.path()).collect();
         for f in &files {

apps/figcraft/src/recovery_tests.rs

@@ -167,6 +167,23 @@ fn a_normal_quit_removes_the_recovered_copies_it_took_over() {
     let _ = std::fs::remove_dir_all(&root);
 }
 
+#[test]
+fn quitting_without_the_unsaved_question_keeps_copies_for_the_next_start() {
+    let root = root("quitunasked");
+    // macOS's Quit menu: nothing asked, so the unsaved document comes back next time.
+    let s = edited();
+    Recovery::start(&root).unwrap().quit(&s, false);
+    let mut next = Session::empty();
+    assert_eq!(recover(&root, &mut next), 1);
+    let _ = std::fs::remove_dir_all(&root);
+    // Asked (saved or discarded on purpose), or nothing unsaved: nothing is left.
+    for (s, asked) in [(edited(), true), (Session::new(), false)] {
+        Recovery::start(&root).unwrap().quit(&s, asked);
+        assert!(std::fs::read_dir(&root).unwrap().next().is_none(), "asked: {asked}");
+    }
+    let _ = std::fs::remove_dir_all(&root);
+}
+
 #[test]
 fn a_run_whose_folder_name_is_still_held_takes_another() {
     let root = root("pidreuse");
@@ -186,6 +203,29 @@ fn a_run_whose_folder_name_is_still_held_takes_another() {
     let _ = std::fs::remove_dir_all(&root);
 }
 
+/// #334: a lock that frees itself is not a run that is still going. A child between its `fork` and
+/// its `exec` inherits the run's open descriptors and a `flock` lasts while any descriptor for the
+/// file is open, so a crashed run's copies must still come back once that child has exec'd.
+#[cfg(unix)]
+#[test]
+fn a_lock_freed_a_moment_later_is_not_a_run_that_is_still_going() {
+    let root = root("fork-window");
+    crashed(&edited(), &root);
+    // Hold the crashed run's folder lock on a second descriptor, the way a child forked before its
+    // exec holds it, and free it shortly after.
+    let lock = std::fs::File::options().write(true).create(true).truncate(false).open(root.join("crashed").join("lock")).unwrap();
+    lock.try_lock().unwrap();
+    let freed = std::thread::spawn(move || {
+        std::thread::sleep(std::time::Duration::from_millis(10));
+        drop(lock);
+    });
+    // The next start waits for that lock rather than reading the run as still going.
+    let mut next = Session::empty();
+    assert_eq!(recover(&root, &mut next), 1, "the copies come back once the lock frees itself");
+    freed.join().unwrap();
+    let _ = std::fs::remove_dir_all(&root);
+}
+
 /// The rectangles in `doc`.
 fn rectangles(doc: &figcraft_engine::doc::Document) -> usize {
     doc.nodes().filter(|n| matches!(n.kind, figcraft_engine::doc::NodeKind::Rectangle)).count()

apps/figcraft/src/services.rs

@@ -167,10 +167,18 @@ fn reveal(path: &Path) -> std::io::Result<()> {
 /// The preferences' file in the config folder.
 const STATE: &str = "state.json";
 
-pub fn save_state(app: &FigApp) {
-    if let Some(dir) = config_dir() {
-        write_prefs(&dir, &app.session.prefs);
+/// Everything quitting keeps, all done when it returns (macOS then ends the process): the
+/// preferences in `dir`, this run's recovery copies ([`Recovery::quit`](crate::recovery::Recovery::quit))
+/// and the live sessions' ends (one this app hosts tells everyone and stops; a joined one leaves).
+pub fn shutdown(app: &mut FigApp, dir: Option<&Path>, recovery: Option<crate::recovery::Recovery>) {
+    if let Some(dir) = dir {
+        write_prefs(dir, &app.session.prefs);
     }
+    // Before the sessions end: a recovered online file's copy waits for its session's outcome.
+    if let Some(r) = recovery {
+        r.quit(&app.session, app.ui.quit);
+    }
+    drop(std::mem::take(&mut app.session.live));
 }
 
 /// Write `prefs` to `dir` atomically (a temporary file renamed over the old one: a crash leaves

apps/figcraft/src/services_tests.rs

@@ -82,3 +82,38 @@ fn preferences_are_readable_by_their_owner_only() {
     assert_eq!(mode(&dir.join("state.json")), 0o600);
     let _ = std::fs::remove_dir_all(&dir);
 }
+
+/// A live link that only records the sessions it was told to leave.
+struct Leaves(Arc<Mutex<Vec<u64>>>);
+
+impl figcraft_engine::live::LiveLink for Leaves {
+    fn host(&mut self, _: u64, _: figcraft_engine::live::HostOptions) -> Result<figcraft_engine::live::SessionInfo, String> {
+        Err("not in this test".into())
+    }
+    fn join(&mut self, _: u64, _: &str, _: &str) -> Result<(), String> {
+        Ok(())
+    }
+    fn leave(&mut self, session: u64) {
+        self.0.lock().unwrap().push(session);
+    }
+    fn presence(&mut self, _: u64, _: &figcraft_engine::live::Presence) {}
+    fn send(&mut self, _: u64, _: figcraft_engine::figcraft_collab::message::ClientMsg) {}
+    fn poll(&mut self) -> Vec<(u64, figcraft_engine::live::Event)> {
+        Vec::new()
+    }
+}
+
+#[test]
+fn quitting_keeps_the_preferences_and_ends_the_live_sessions() {
+    let dir = root("shutdown");
+    let mut fig = start(&dir);
+    let left = Arc::new(Mutex::new(Vec::new()));
+    fig.session.live.install(Box::new(Leaves(left.clone())));
+    let joined = fig.run("collab.join", json!({"link": "ws://127.0.0.1:9/?file=f1&token=EditSecretEditSecret00"})).unwrap();
+    fig.session.prefs.user_name = "Ada".into();
+    crate::services::shutdown(&mut fig, Some(&dir), None);
+    assert_eq!(*left.lock().unwrap(), [joined["session"].as_u64().unwrap()], "the session was left");
+    assert!(!fig.session.live.available(), "nothing is left to send on");
+    assert_eq!(start(&dir).session.prefs.user_name, "Ada", "the preferences were kept");
+    let _ = std::fs::remove_dir_all(&dir);
+}

contributors/people.toml

@@ -44,3 +44,15 @@ sync_github_name = true
 
 [people.volkovskey]
 real_name = "Andrii Volkov"
+
+[people.marcoarnulfo]
+real_name = "Marco Arnulfo"
+display_name = "Marco Arnulfo"
+sync_github_name = false
+
+[people.krinry]
+display_name = "krinry"
+sync_github_name = true
+
+[people.pechnikov2026-star]
+sync_github_name = true

crates/collab-net/src/invite.rs

@@ -203,7 +203,7 @@ fn pairs(query: &str) -> Result<Vec<(String, String)>, String> {
 fn with_port(authority: &str, default: u16) -> String {
     let has_port = match authority.rsplit_once(':') {
         // `[v6]` alone has colons inside the brackets only.
-        Some((h, p)) => !(h.starts_with('[') && !h.ends_with(']')) && !p.contains(']'),
+        Some((h, p)) => (!h.starts_with('[') || h.ends_with(']')) && !p.contains(']'),
         None => false,
     };
     if has_port { authority.to_string() } else { format!("{authority}:{default}") }

crates/collab-net/src/limits.rs

@@ -12,7 +12,9 @@ pub struct NetLimits {
     /// before: its hello.
     pub max_client_message: usize,
     pub max_hello: usize,
-    /// Largest message a client accepts from the host (a welcome carries the whole document).
+    /// Largest message a client accepts from the host (a welcome carries the whole document): 1 GiB,
+    /// room for any file up to 1023 MiB and well past the servers' defaults, while a hostile server
+    /// (any link can name one) can't make the app or a browser tab buffer more than that.
     pub max_server_message: usize,
     /// Messages a client may send per second on average, and in a burst; beyond that it is
     /// disconnected.
@@ -61,7 +63,7 @@ impl Default for NetLimits {
             max_connections: 64,
             max_client_message: figcraft_collab::Limits::default().max_message_bytes,
             max_hello: 64 << 10,
-            max_server_message: figcraft_collab::Limits::default().max_message_bytes,
+            max_server_message: 1 << 30,
             rate: 100.0,
             burst: 400.0,
             hello_timeout: Duration::from_secs(10),

crates/collab/src/change.rs

@@ -87,8 +87,9 @@ macro_rules! node_props {
     ($($variant:ident => $field:ident),* $(,)?) => {
         /// A node property: the tree position (`parent`, `position`) or one saved field of
         /// [`Node`]. List-valued fields (fills, text runs, vector networks…) are one property each,
-        /// replaced whole (three-way merges line fills, strokes and effects up item by item, see
-        /// [`merge`](crate::merge)). New properties go at the end (the binary form numbers them).
+        /// replaced whole (three-way merges line the lists whose items stand on their own, such as
+        /// fills, up item by item, see [`merge`](crate::merge)). New properties go at the end (the
+        /// binary form numbers them).
         #[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
         #[serde(rename_all = "camelCase")]
         pub enum Prop {

crates/collab/src/merge.rs

@@ -4,12 +4,13 @@
 //!
 //! A conflict is the same property (or document-level entry) changed on both sides to different
 //! values, or a layer deleted on one side while the other side edited it or something inside it
-//! (including adding layers to it or moving layers into or out of it). Fills, strokes and effects
-//! merge item by item: both sides changing different items of the list (or one adding items at its
-//! end) is no conflict, only the same item changed both ways or the list shortened on a side
-//! while the other changed it. Nothing that conflicts is
-//! merged until it is resolved: each conflict is resolved for one side, and the other side's
-//! changes to it are left out. Everything else from both sides is kept.
+//! (including adding layers to it or moving layers into or out of it). The layer lists whose items
+//! stand on their own (fills, strokes, effects, layout grids, export settings, guides, prototype
+//! interactions, accessibility annotations and Dev Mode resources) merge item by item: both sides
+//! changing different items of the list (or one adding items at its end) is no conflict, only the
+//! same item changed both ways or the list shortened on a side while the other changed it. Nothing
+//! that conflicts is merged until it is resolved: each conflict is resolved for one side, and the
+//! other side's changes to it are left out. Everything else from both sides is kept.
 
 use std::collections::{BTreeMap, BTreeSet};
 use std::fmt;
@@ -159,8 +160,23 @@ fn by_key(changes: &[Change]) -> BTreeMap<Key, Vec<usize>> {
     out
 }
 
-/// List properties whose items merge one by one.
-const PER_ITEM: &[Prop] = &[Prop::Fills, Prop::Strokes, Prop::Effects];
+/// List properties whose items merge one by one: the items stand on their own, so both sides
+/// changing different ones (or one side adding at its end) is no conflict. Sets and keyed maps
+/// (`bound`, `varModes`, `overrides`, `propRefs`, `pluginData`) are not here: their items line up
+/// by key, not by position.
+const PER_ITEM: &[Prop] = &[
+    Prop::Fills,
+    Prop::Strokes,
+    Prop::Effects,
+    Prop::Grids,
+    Prop::Exports,
+    Prop::Guides,
+    Prop::Interactions,
+    Prop::Annotations,
+    // Not `CodeLinks`: there is one per language, and lining them up by position could leave two
+    // for one language (the second hidden), so they merge whole.
+    Prop::DevResources,
+];
 
 /// Both sides' writes `b` and `m` of list property `key` merged item by item against the base
 /// (see [`merge_items`]); `None` when `key` isn't such a list or the writes conflict.

crates/collab/src/merge_list_tests.rs

@@ -1,8 +1,10 @@
-//! Fills, strokes and effects merge item by item: different items changed on each side merge,
-//! the same item changed both ways conflicts.
+//! The layer lists whose items stand on their own (fills, strokes, effects, layout grids, export
+//! settings, guides, prototype interactions, accessibility annotations and Dev Mode resources)
+//! merge item by item: different items changed on each side merge, the same item changed both ways
+//! conflicts.
 
 use figcraft_color::{Color, Paint};
-use figcraft_doc::{Document, Effect, NodeId, NodeKind};
+use figcraft_doc::{Document, Effect, LayoutGrid, NodeId, NodeKind, proto};
 use serde_json::{Value, json};
 
 use crate::merge::{Key, Side, merge_items, plan};
@@ -100,19 +102,113 @@ fn the_same_item_changed_both_ways_conflicts() {
 }
 
 #[test]
-fn other_lists_still_conflict_as_a_whole() {
-    // Docs silent: lists other than fills, strokes and effects (export settings here) still
-    // conflict whole when both sides change them.
+fn the_other_item_lists_merge_one_by_one_too() {
+    // Layout grids, export settings, guides, accessibility annotations and Dev Mode resources are
+    // item lists like fills: both sides changing different items merges.
     let (mut base, _, _, r) = files();
     let export = |suffix: &str| figcraft_doc::ExportSetting { suffix: suffix.into(), ..Default::default() };
-    base.get_mut(r).unwrap().exports = vec![export("@1"), export("@2")];
+    let guide = |vertical: bool, offset: f64| figcraft_doc::Guide { vertical, offset };
+    let annot = |label: &str| figcraft_doc::Annotation { label: label.into(), properties: Vec::new(), category: None };
+    let grid = |size: f64| LayoutGrid { size, ..Default::default() };
+    let res = |url: &str| figcraft_doc::DevResource { url: url.into(), name: String::new() };
+    let n = base.get_mut(r).unwrap();
+    n.exports = vec![export("@1"), export("@2")];
+    n.guides = vec![guide(true, 10.0), guide(false, 20.0)];
+    n.annotations = vec![annot("a1"), annot("a2")];
+    n.grids = vec![grid(10.0), grid(20.0)];
+    n.dev_resources = vec![res("https://a.test"), res("https://b.test")];
     let (mut branch, mut main) = (base.clone(), base.clone());
     branch.set_client_id(base.highest_id_space() + 1);
-    branch.get_mut(r).unwrap().exports[0] = export("@b");
-    main.get_mut(r).unwrap().exports[1] = export("@m");
+    // The branch changes the first item of each list; main the second.
+    let b = branch.get_mut(r).unwrap();
+    (b.exports[0].suffix, b.guides[0].offset, b.annotations[0].label, b.grids[0].size, b.dev_resources[0].url) =
+        ("@b".into(), 11.0, "b1".into(), 12.0, "https://branch.test".into());
+    let m = main.get_mut(r).unwrap();
+    (m.exports[1].suffix, m.guides[1].offset, m.annotations[1].label, m.grids[1].size, m.dev_resources[1].url) =
+        ("@m".into(), 22.0, "m2".into(), 24.0, "https://main.test".into());
+    both_ways(&base, &branch, &main, |doc| {
+        let n = doc.node(r).unwrap();
+        let suffixes: Vec<&str> = n.exports.iter().map(|e| e.suffix.as_str()).collect();
+        assert_eq!(suffixes, ["@b", "@m"], "export settings");
+        let offsets: Vec<f64> = n.guides.iter().map(|g| g.offset).collect();
+        assert_eq!(offsets, [11.0, 22.0], "guides");
+        let labels: Vec<&str> = n.annotations.iter().map(|a| a.label.as_str()).collect();
+        assert_eq!(labels, ["b1", "m2"], "annotations");
+        let sizes: Vec<f64> = n.grids.iter().map(|g| g.size).collect();
+        assert_eq!(sizes, [12.0, 24.0], "layout grids");
+        let urls: Vec<&str> = n.dev_resources.iter().map(|d| d.url.as_str()).collect();
+        assert_eq!(urls, ["https://branch.test", "https://main.test"], "dev resources");
+    });
+}
+
+#[test]
+fn the_same_item_of_another_list_changed_both_ways_conflicts() {
+    let (mut base, _, _, r) = files();
+    let link = |language: &str| figcraft_doc::CodeLink { language: language.into(), ..Default::default() };
+    let n = base.get_mut(r).unwrap();
+    n.exports = vec![
+        figcraft_doc::ExportSetting { suffix: "@1".into(), ..Default::default() },
+        figcraft_doc::ExportSetting { suffix: "@2".into(), ..Default::default() },
+    ];
+    n.code_links = vec![link("react"), link("vue")];
+    let (mut branch, mut main) = (base.clone(), base.clone());
+    branch.set_client_id(base.highest_id_space() + 1);
+    branch.get_mut(r).unwrap().exports[0].suffix = "@b".into();
+    main.get_mut(r).unwrap().exports[0].suffix = "@m".into();
+    // Code links are one per language, not an item list: different links changed still conflict.
+    branch.get_mut(r).unwrap().code_links[0].name = "B".into();
+    main.get_mut(r).unwrap().code_links[1].name = "M".into();
     let p = plan(&base, &branch, &main).unwrap();
-    let keys: Vec<String> = p.conflicts.iter().map(|c| c.key.to_string()).collect();
-    assert_eq!(keys, [format!("{r}/exports")]);
+    let mut keys: Vec<String> = p.conflicts.iter().map(|c| c.key.to_string()).collect();
+    keys.sort();
+    let mut want = [format!("{r}/codeLinks"), format!("{r}/exports")];
+    want.sort();
+    assert_eq!(keys, want);
+}
+
+#[test]
+fn interactions_merge_item_by_item() {
+    let ia = |duration_ms: u32| proto::Interaction {
+        trigger: Default::default(),
+        actions: vec![proto::Action::Back],
+        transition: Default::default(),
+        duration_ms,
+        easing: Default::default(),
+        delay_ms: 0,
+    };
+    let durations = |doc: &Document, r: NodeId| doc.node(r).unwrap().interactions.iter().map(|i| i.duration_ms).collect::<Vec<_>>();
+    let (mut base, _, _, r) = files();
+    base.get_mut(r).unwrap().interactions = vec![ia(100), ia(200)];
+    let fork = || {
+        let (mut branch, main) = (base.clone(), base.clone());
+        branch.set_client_id(base.highest_id_space() + 1);
+        (branch, main)
+    };
+    // The branch changes the first interaction and adds one; main changes the second.
+    let (mut branch, mut main) = fork();
+    branch.get_mut(r).unwrap().interactions[0].duration_ms = 150;
+    branch.get_mut(r).unwrap().interactions.push(ia(300));
+    main.get_mut(r).unwrap().interactions[1].duration_ms = 250;
+    both_ways(&base, &branch, &main, |doc| assert_eq!(durations(doc, r), [150, 250, 300]));
+    // The branch deletes one while main leaves them alone.
+    let (mut branch, mut main) = fork();
+    branch.get_mut(r).unwrap().interactions.remove(0);
+    main.get_mut(r).unwrap().fills[0] = red();
+    both_ways(&base, &branch, &main, |doc| assert_eq!(durations(doc, r), [200]));
+    // The same interaction changed both ways, or one deleted while the other side changed the
+    // list, conflicts.
+    for delete in [false, true] {
+        let (mut branch, mut main) = fork();
+        if delete {
+            branch.get_mut(r).unwrap().interactions.remove(0);
+        } else {
+            branch.get_mut(r).unwrap().interactions[1].duration_ms = 220;
+        }
+        main.get_mut(r).unwrap().interactions[1].duration_ms = 250;
+        let p = plan(&base, &branch, &main).unwrap();
+        let keys: Vec<String> = p.conflicts.iter().map(|c| c.key.to_string()).collect();
+        assert_eq!(keys, [format!("{r}/interactions")], "delete: {delete}");
+    }
 }
 
 #[test]

crates/doc/src/lib.rs

@@ -77,17 +77,19 @@ pub enum DocError {
 
 pub type DocResult<T> = Result<T, DocError>;
 
-/// The set of touched node ids, and whether any layer is a mask (worked out when first asked
-/// after a change: hit testing skips its mask checks without one). Never part of equality or
+/// The set of touched node ids, whether any layer is a mask (hit testing skips its mask checks
+/// without one) and the largest background blur radius (renders keep that much overlap between
+/// their bands), both worked out when first asked after a change. Never part of equality or
 /// serialisation.
 #[derive(Clone, Debug, Default)]
-pub struct Dirty(pub std::collections::BTreeSet<NodeId>, std::sync::OnceLock<bool>);
+pub struct Dirty(pub std::collections::BTreeSet<NodeId>, std::sync::OnceLock<bool>, std::sync::OnceLock<f64>);
 
 impl Dirty {
     /// Record node `id` as touched (edited, added or removed).
     fn touch(&mut self, id: NodeId) {
         self.0.insert(id);
         self.1 = std::sync::OnceLock::new();
+        self.2 = std::sync::OnceLock::new();
     }
 }
 
@@ -254,6 +256,11 @@ impl Document {
         *self.dirty.1.get_or_init(|| self.nodes.values().any(|n| n.is_mask))
     }
 
+    /// The largest background blur or glass radius of any layer's effects (0 without any).
+    pub fn max_backdrop_radius(&self) -> f64 {
+        *self.dirty.2.get_or_init(|| self.nodes.values().flat_map(|n| n.effects.iter()).map(Effect::backdrop_radius).fold(0.0, f64::max))
+    }
+
     /// Node ids touched so far (without clearing).
     pub fn dirty(&self) -> &std::collections::BTreeSet<NodeId> {
         &self.dirty.0
@@ -1117,8 +1124,14 @@ impl Document {
     /// mask with the layers above it up to the next mask, or a single layer. An auto layout frame
     /// whose first child paints on top paints the runs in reverse (see [`Node::paint_order`]).
     pub fn paint_runs(&self, n: &Node) -> Vec<std::ops::Range<usize>> {
-        let kids = &n.children;
-        let node = |i: usize| kids.get(i).and_then(|k| self.node(*k));
+        let kids: Vec<Option<&Node>> = n.children.iter().map(|k| self.node(*k)).collect();
+        Self::paint_runs_of(&kids, n.layout.as_ref().is_some_and(|l| l.reverse_z))
+    }
+
+    /// [`Self::paint_runs`] of children already looked up (`None`: not in the document), last run
+    /// first when `reverse_z`.
+    pub fn paint_runs_of(kids: &[Option<&Node>], reverse_z: bool) -> Vec<std::ops::Range<usize>> {
+        let node = |i: usize| kids.get(i).copied().flatten();
         let mut runs = Vec::new();
         let mut i = 0;
         while i < kids.len() {
@@ -1131,7 +1144,7 @@ impl Document {
             runs.push(i..j);
             i = j;
         }
-        if n.layout.as_ref().is_some_and(|l| l.reverse_z) {
+        if reverse_z {
             runs.reverse();
         }
         runs

crates/doc/src/proto.rs

@@ -860,7 +860,35 @@ pub struct Device {
 
 impl PrototypeSettings {
     /// The devices to pick from ("None" presents the frame at its own size).
-    pub const DEVICES: [Device; 6] = [
+    pub const DEVICES: [Device; 19] = [
+        Device {
+            name: "iPhone 17",
+            width: 402.0,
+            height: 874.0,
+            rotates: true,
+            colors: &[c("Black", 0x38, 0x39, 0x3D), c("White", 0xE9, 0xE9, 0xE5)],
+        },
+        Device {
+            name: "iPhone 17 Pro",
+            width: 402.0,
+            height: 874.0,
+            rotates: true,
+            colors: &[c("Black", 0x38, 0x39, 0x3D), c("Silver", 0xD7, 0xD7, 0xD5)],
+        },
+        Device {
+            name: "iPhone 17 Pro Max",
+            width: 440.0,
+            height: 956.0,
+            rotates: true,
+            colors: &[c("Black", 0x38, 0x39, 0x3D), c("Silver", 0xD7, 0xD7, 0xD5)],
+        },
+        Device {
+            name: "iPhone Air",
+            width: 420.0,
+            height: 912.0,
+            rotates: true,
+            colors: &[c("Black", 0x38, 0x39, 0x3D), c("Silver", 0xD7, 0xD7, 0xD5)],
+        },
         Device {
             name: "iPhone 16",
             width: 393.0,
@@ -874,6 +902,13 @@ impl PrototypeSettings {
                 c("Blue", 0x72, 0x84, 0xD4),
             ],
         },
+        Device {
+            name: "iPhone 16 Pro",
+            width: 402.0,
+            height: 874.0,
+            rotates: true,
+            colors: &[c("Black", 0x3B, 0x3A, 0x38), c("White", 0xEC, 0xEB, 0xE6)],
+        },
         Device {
             name: "iPhone 16 Pro Max",
             width: 440.0,
@@ -881,6 +916,55 @@ impl PrototypeSettings {
             rotates: true,
             colors: &[c("Black", 0x3B, 0x3A, 0x38), c("White", 0xEC, 0xEB, 0xE6), c("Natural", 0xBF, 0xB9, 0xAF), c("Sand", 0xC6, 0xAC, 0x8F)],
         },
+        Device {
+            name: "iPhone 16 Plus",
+            width: 430.0,
+            height: 932.0,
+            rotates: true,
+            colors: &[c("Black", 0x3A, 0x3B, 0x3F), c("White", 0xEE, 0xED, 0xE8)],
+        },
+        Device {
+            name: "iPhone 15 Pro",
+            width: 393.0,
+            height: 852.0,
+            rotates: true,
+            colors: &[c("Black", 0x3B, 0x3A, 0x38), c("Silver", 0xD7, 0xD7, 0xD5)],
+        },
+        Device {
+            name: "iPhone 15 Pro Max",
+            width: 430.0,
+            height: 932.0,
+            rotates: true,
+            colors: &[c("Black", 0x3B, 0x3A, 0x38), c("Silver", 0xD7, 0xD7, 0xD5)],
+        },
+        Device {
+            name: "iPhone 15 Plus",
+            width: 430.0,
+            height: 932.0,
+            rotates: true,
+            colors: &[c("Black", 0x3A, 0x3B, 0x3F), c("White", 0xEE, 0xED, 0xE8)],
+        },
+        Device {
+            name: "iPhone 14 Pro",
+            width: 393.0,
+            height: 852.0,
+            rotates: true,
+            colors: &[c("Black", 0x3B, 0x3A, 0x38), c("Silver", 0xD7, 0xD7, 0xD5)],
+        },
+        Device {
+            name: "iPhone 14 Pro Max",
+            width: 430.0,
+            height: 932.0,
+            rotates: true,
+            colors: &[c("Black", 0x3B, 0x3A, 0x38), c("Silver", 0xD7, 0xD7, 0xD5)],
+        },
+        Device {
+            name: "iPhone 14",
+            width: 390.0,
+            height: 844.0,
+            rotates: true,
+            colors: &[c("Black", 0x3A, 0x3B, 0x3F), c("White", 0xEE, 0xED, 0xE8)],
+        },
         Device {
             name: "Android Compact",
             width: 412.0,
@@ -888,6 +972,13 @@ impl PrototypeSettings {
             rotates: true,
             colors: &[c("Black", 0x2E, 0x2F, 0x33), c("Silver", 0xD6, 0xD8, 0xDB), c("Green", 0xA6, 0xC0, 0xA3)],
         },
+        Device {
+            name: "Android Medium",
+            width: 700.0,
+            height: 840.0,
+            rotates: true,
+            colors: &[c("Black", 0x2E, 0x2F, 0x33), c("Silver", 0xD6, 0xD8, 0xDB)],
+        },
         Device {
             name: "iPad mini",
             width: 744.0,

crates/engine/Cargo.toml

@@ -20,6 +20,7 @@ figcraft-render = { workspace = true }
 figcraft-format = { workspace = true }
 figcraft-svg = { workspace = true }
 figcraft-pdf = { workspace = true }
+craft-docpath = { workspace = true }
 figcraft-plugin = { workspace = true }
 serde = { workspace = true }
 serde_json = { workspace = true }

crates/engine/clippy.toml

@@ -0,0 +1,39 @@
+# The workspace settings (../../clippy.toml; clippy reads only the nearest file), plus the engine's
+# own rule: shipped engine code reaches the file system only through `file_access`, which enforces
+# the automation roots (#715), so every command is confined without a check of its own.
+allow-unwrap-in-tests = true
+allow-expect-in-tests = true
+allow-panic-in-tests = true
+too-many-arguments-threshold = 10
+disallowed-methods = [
+    { path = "std::fs::read", reason = "use file_access::read (automation roots)" },
+    { path = "std::fs::read_to_string", reason = "use file_access::read (automation roots)" },
+    { path = "std::fs::write", reason = "use file_access::write (automation roots)" },
+    { path = "std::fs::metadata", reason = "use file_access::metadata (automation roots)" },
+    { path = "std::fs::symlink_metadata", reason = "use file_access (automation roots)" },
+    { path = "std::fs::read_dir", reason = "use file_access::read_dir (automation roots)" },
+    { path = "std::fs::canonicalize", reason = "use file_access (automation roots)" },
+    { path = "std::fs::copy", reason = "use file_access (automation roots)" },
+    { path = "std::fs::rename", reason = "use file_access (automation roots)" },
+    { path = "std::fs::create_dir", reason = "use file_access::create_dir_all (automation roots)" },
+    { path = "std::fs::create_dir_all", reason = "use file_access::create_dir_all (automation roots)" },
+    { path = "std::fs::remove_file", reason = "use file_access (automation roots)" },
+    { path = "std::fs::remove_dir", reason = "use file_access (automation roots)" },
+    { path = "std::fs::remove_dir_all", reason = "use file_access (automation roots)" },
+    { path = "std::fs::hard_link", reason = "use file_access (automation roots)" },
+    { path = "std::fs::File::open", reason = "use file_access::open (automation roots)" },
+    { path = "std::fs::File::create", reason = "use file_access::write (automation roots)" },
+    { path = "std::fs::File::create_new", reason = "use file_access::write (automation roots)" },
+    { path = "std::fs::OpenOptions::open", reason = "use file_access (automation roots)" },
+    { path = "std::path::Path::exists", reason = "use file_access::exists (automation roots)" },
+    { path = "std::path::Path::try_exists", reason = "use file_access::exists (automation roots)" },
+    { path = "std::path::Path::is_file", reason = "use file_access::metadata (automation roots)" },
+    { path = "std::path::Path::is_dir", reason = "use file_access::is_dir (automation roots)" },
+    { path = "std::path::Path::metadata", reason = "use file_access::metadata (automation roots)" },
+    { path = "std::path::Path::symlink_metadata", reason = "use file_access (automation roots)" },
+    { path = "std::path::Path::read_dir", reason = "use file_access::read_dir (automation roots)" },
+    { path = "std::path::Path::canonicalize", reason = "use file_access (automation roots)" },
+    { path = "figcraft_format::write_file_atomic", reason = "use file_access::write (automation roots)" },
+    { path = "figcraft_format::save_file", reason = "use file_access::write (automation roots)" },
+    { path = "figcraft_format::load_file", reason = "use file_access::read (automation roots)" },
+]

crates/engine/src/al_behaviour_tests.rs

@@ -180,6 +180,23 @@ fn vertical_wrap_columns_take_arrows_and_drops() {
     assert_eq!(line, Some([30.0, 48.0, 50.0, 48.0]));
 }
 
+#[test]
+fn adding_auto_layout_to_a_frame_keeps_its_size() {
+    // An existing frame with content hugs it (padding inferred, so the size is preserved);
+    // an empty one keeps its size instead of collapsing to its padding.
+    let mut s = Session::new();
+    let f = id(s.execute("frame.create", &json!({"x": 0, "y": 0, "width": 300, "height": 200})).unwrap());
+    rect(&mut s, f, 40.0, 20.0, "#FF0000");
+    s.execute("layout.add", &json!({"ids": [f]})).unwrap();
+    assert_eq!(sizing(&s, f), (Sizing::Hug, Sizing::Hug));
+    assert_eq!(size(&s, f), (300.0, 200.0));
+    // An empty frame keeps its size too.
+    let e = id(s.execute("frame.create", &json!({"x": 0, "y": 0, "width": 300, "height": 200})).unwrap());
+    s.execute("layout.add", &json!({"ids": [e]})).unwrap();
+    assert_eq!(sizing(&s, e), (Sizing::Fixed, Sizing::Fixed));
+    assert_eq!(size(&s, e), (300.0, 200.0));
+}
+
 #[test]
 fn canvas_stacking_paints_and_exports_the_first_child_on_top() {
     // Documented: the last child is on top by default; "first on top" flips which one is drawn

crates/engine/src/binding_lists_tests.rs

@@ -46,7 +46,7 @@ fn a_bound_fill_colour_keeps_the_other_fills() {
     let fills = s.doc().unwrap().node(r).unwrap().fills.clone();
     assert_eq!(fills.len(), 2, "the second fill stays");
     assert_eq!(fills[0].kind, PaintKind::Solid { color: Color::from_rgb8_const(0xFF, 0, 0) });
-    assert_eq!(fills[0].opacity, 0.5, "the bound paint keeps its opacity");
+    assert_eq!(fills[0].opacity, 1.0, "the variable brings the whole colour, alpha included");
     assert_eq!(fills[1].kind, PaintKind::Solid { color: Color::from_rgb8_const(0, 0xFF, 0) });
     // Removing the bound (first) fill takes the binding with it.
     ex(&mut s, "fill.remove", json!({"ids": [r], "index": 0}));

crates/engine/src/bound_alpha_tests.rs

@@ -0,0 +1,131 @@
+//! A colour variable's alpha applies once to the paint it is bound to (#802): a `#RRGGBBAA` fill keeps
+//! its alpha in the paint opacity, and binding a variable with alpha hands the variable the whole
+//! colour, so the two alphas don't multiply (canvas, SVG, `.fig` round trips, mode switches).
+
+use figcraft_doc::NodeId;
+use serde_json::json;
+
+use crate::Session;
+
+/// 0x80 / 255 and 0x40 / 255.
+const HALF: f32 = 128.0 / 255.0;
+const QUARTER: f32 = 64.0 / 255.0;
+
+fn ex(s: &mut Session, cmd: &str, p: serde_json::Value) {
+    s.execute(cmd, &p).unwrap_or_else(|e| panic!("{cmd}: {e}"));
+}
+
+/// A rectangle filled `#0D6EFD80` and a colour variable `tint` (Light `light`, Dark `dark`).
+fn setup(light: &str, dark: &str) -> (Session, NodeId) {
+    let mut s = Session::new();
+    let r = s.execute("shape.rectangle", &json!({"x": 0, "y": 0, "width": 10, "height": 10, "props": {"fill": "#0D6EFD80"}})).unwrap();
+    let r = NodeId(r["id"].as_u64().unwrap());
+    ex(&mut s, "variable.createCollection", json!({"name": "Tokens", "modes": ["Light", "Dark"]}));
+    ex(&mut s, "variable.create", json!({"collection": "Tokens", "name": "tint", "type": "color", "value": light}));
+    ex(&mut s, "variable.set", json!({"variable": "tint", "mode": "Dark", "value": dark}));
+    (s, r)
+}
+
+/// The fill's effective alpha (colour alpha times paint opacity).
+fn alpha(s: &Session, r: NodeId) -> f32 {
+    s.doc().unwrap().node(r).unwrap().fills[0].solid_color().unwrap().a
+}
+
+/// The alpha byte of the rectangle rendered on its own (transparent backdrop).
+fn pixel_alpha(s: &Session, r: NodeId) -> u8 {
+    let pix = figcraft_render::render_node(s.doc().unwrap(), r, 1.0).unwrap();
+    let i = ((5 * pix.width() + 5) * 4 + 3) as usize;
+    pix.data()[i]
+}
+
+fn near(a: f32, b: f32) -> bool {
+    (a - b).abs() < 2e-3
+}
+
+#[test]
+fn a_hex_with_alpha_keeps_its_alpha_in_the_opacity() {
+    let (s, r) = setup("#0D6EFD80", "#0D6EFD40");
+    let p = &s.doc().unwrap().node(r).unwrap().fills[0];
+    assert_eq!(p.kind, figcraft_color::PaintKind::Solid { color: figcraft_color::Color::from_rgb8_const(0x0D, 0x6E, 0xFD) });
+    assert!(near(p.opacity, HALF));
+    assert_eq!(pixel_alpha(&s, r), 128);
+}
+
+#[test]
+fn a_bound_variable_alpha_applies_once() {
+    // The fill and the variable are both #0D6EFD80: the result is 50%, not 25%.
+    let (mut s, r) = setup("#0D6EFD80", "#0D6EFD40");
+    ex(&mut s, "variable.bind", json!({"ids": [r.0], "field": "fill", "variable": "tint"}));
+    assert!(near(alpha(&s, r), HALF), "{}", alpha(&s, r));
+    assert_eq!(pixel_alpha(&s, r), 128);
+    let svg = figcraft_svg::export_svg(s.doc().unwrap(), &[r], &figcraft_svg::SvgOptions::default()).unwrap();
+    assert!(svg.contains("fill=\"#0D6EFD\" fill-opacity=\"0.502\""), "{svg}");
+    // Binding the same variable again changes nothing.
+    ex(&mut s, "variable.bind", json!({"ids": [r.0], "field": "fill", "variable": "tint"}));
+    assert!(near(alpha(&s, r), HALF));
+}
+
+#[test]
+fn unbinding_keeps_the_colour_with_its_alpha_in_the_opacity() {
+    let (mut s, r) = setup("#0D6EFD40", "#0D6EFD");
+    ex(&mut s, "variable.bind", json!({"ids": [r.0], "field": "fill", "variable": "tint"}));
+    assert_eq!(pixel_alpha(&s, r), 64);
+    ex(&mut s, "variable.bind", json!({"ids": [r.0], "field": "fill", "variable": null}));
+    let p = &s.doc().unwrap().node(r).unwrap().fills[0];
+    assert_eq!(p.kind, figcraft_color::PaintKind::Solid { color: figcraft_color::Color::from_rgb8_const(0x0D, 0x6E, 0xFD) });
+    assert!(near(p.opacity, QUARTER), "{}", p.opacity);
+    assert_eq!(pixel_alpha(&s, r), 64);
+    // Undo restores the binding and its paint.
+    ex(&mut s, "edit.undo", json!({}));
+    assert!(!s.doc().unwrap().node(r).unwrap().bound.is_empty());
+    assert_eq!(pixel_alpha(&s, r), 64);
+}
+
+#[test]
+fn modes_switch_the_alpha_without_accumulating() {
+    let (mut s, r) = setup("#0D6EFD40", "#0D6EFD80");
+    ex(&mut s, "variable.bind", json!({"ids": [r.0], "field": "fill", "variable": "tint"}));
+    for (mode, want) in [("Dark", HALF), ("Light", QUARTER), ("Dark", HALF), ("Light", QUARTER)] {
+        ex(&mut s, "variable.setMode", json!({"collection": "Tokens", "mode": mode}));
+        assert!(near(alpha(&s, r), want), "{mode}: {}", alpha(&s, r));
+    }
+    // An opacity set while bound multiplies on top and survives mode switches.
+    ex(&mut s, "fill.set", json!({"ids": [r.0], "index": 0, "opacity": 0.5}));
+    ex(&mut s, "variable.setMode", json!({"collection": "Tokens", "mode": "Dark"}));
+    assert!(near(alpha(&s, r), HALF * 0.5));
+}
+
+#[test]
+fn node_set_and_style_bindings_apply_the_alpha_once() {
+    let (mut s, r) = setup("#0D6EFD80", "#0D6EFD40");
+    let var = s.doc().unwrap().variables.get("tint").unwrap().id.clone();
+    ex(&mut s, "node.set", json!({"id": r.0, "props": {"boundVariables": {"fill": var}}}));
+    assert!(near(alpha(&s, r), HALF));
+    ex(&mut s, "node.set", json!({"id": r.0, "props": {"boundVariables": {"fill": null}}}));
+    assert!(near(s.doc().unwrap().node(r).unwrap().fills[0].opacity, HALF));
+    // A paint style made from a `#RRGGBBAA` colour, bound to the variable.
+    let st = s.execute("style.create", &json!({"type": "paint", "name": "Tint", "value": "#0D6EFD80"})).unwrap()["id"].clone();
+    ex(&mut s, "style.bind", json!({"style": st, "field": "fills/0/color", "variable": "tint"}));
+    ex(&mut s, "style.apply", json!({"ids": [r.0], "style": st}));
+    assert!(near(alpha(&s, r), HALF), "{}", alpha(&s, r));
+}
+
+#[test]
+fn a_fig_round_trip_keeps_the_alpha_once() {
+    let (mut s, r) = setup("#0D6EFD80", "#0D6EFD40");
+    ex(&mut s, "variable.bind", json!({"ids": [r.0], "field": "fill", "variable": "tint"}));
+    ex(&mut s, "fill.set", json!({"ids": [r.0], "index": 0, "opacity": 0.5}));
+    let (bytes, _) = figcraft_format::fig::export(s.doc().unwrap(), None).unwrap();
+    let back = crate::cmd::file::load_fig(&bytes, "x").unwrap().unwrap().doc;
+    let n = back.nodes().find(|n| !n.bound.is_empty()).unwrap();
+    let a = n.fills[0].solid_color().unwrap().a;
+    assert!(near(a, HALF * 0.5), "{a}");
+}
+
+#[test]
+fn code_gives_a_translucent_stroke_its_alpha_once() {
+    let (mut s, r) = setup("#0D6EFD80", "#0D6EFD40");
+    ex(&mut s, "stroke.add", json!({"ids": [r.0], "color": "#FF000080"}));
+    let code = s.execute("inspect.code", &json!({"id": r.0})).unwrap()["code"].as_str().unwrap_or_default().to_string();
+    assert!(code.contains("solid rgba(255, 0, 0, 0.50)"), "{code}");
+}

crates/engine/src/catalog.rs

@@ -213,6 +213,8 @@ pub static MENU: &[MenuItem] = &[
     m!("Text/Case", "Uppercase", "text.caseUpper"),
     m!("Text/Case", "Lowercase", "text.caseLower"),
     m!("Text/Case", "Title case", "text.caseTitle"),
+    m!("Text", SEP, ""),
+    m!("Text", "Missing fonts…", "text.missingFonts"),
     // Arrange
     m!("Arrange", "Align left", "align.left"),
     m!("Arrange", "Align horizontal centers", "align.hcenter"),
@@ -287,7 +289,7 @@ pub fn items() -> impl Iterator<Item = &'static MenuItem> {
 }
 
 /// Items of FigCraft's own that the parity count leaves out (as it does the `collab.` ones).
-const OWN: [&str; 2] = ["file.newFromTemplate", "help.gettingStarted"];
+const OWN: [&str; 3] = ["file.newFromTemplate", "help.gettingStarted", "text.missingFonts"];
 
 /// Coverage: (implemented, total, missing ids). `extra` lists ids implemented by the UI layer.
 pub fn parity(extra: &[&str]) -> (usize, usize, Vec<&'static str>) {

crates/engine/src/cmd/arrange.rs

@@ -19,6 +19,13 @@ pub fn specs() -> Vec<CommandSpec> {
         spec!("align.bottom", "Align bottom", "{ids?}", true, |s, p| align(s, p, Al::Bottom)),
         spec!("distribute.horizontal", "Distribute horizontal spacing", "{ids?, spacing?}", true, |s, p| distribute(s, p, true)),
         spec!("distribute.vertical", "Distribute vertical spacing", "{ids?, spacing?}", true, |s, p| distribute(s, p, false)),
+        spec!(
+            "arrange.spacing",
+            "Spacing",
+            "{ids?, horizontal?, vertical?, fromGesture?} (page units; fromGesture uses the interaction snapshot)",
+            true,
+            spacing
+        ),
         spec!("arrange.tidy", "Tidy up", "{ids?, spacing?}", true, tidy),
         spec!("arrange.packH", "Pack horizontal", "{ids?}", true, |s, p| pack(s, p, true)),
         spec!("arrange.packV", "Pack vertical", "{ids?}", true, |s, p| pack(s, p, false)),
@@ -546,3 +553,53 @@ pub(crate) fn resize_cmd(s: &mut Session, p: &Value) -> Result<Value> {
     }
     ok()
 }
+
+/// Set the distances between smart-selection tracks without rebuilding/reparenting the layers.
+fn spacing(s: &mut Session, p: &Value) -> Result<Value> {
+    let ids = req_targets("arrange.spacing", s, p)?;
+    // A scrub is absolute from the interaction snapshot, even if tracks overlap or cross.
+    let ds = s.ds()?;
+    let base = ds.interaction.as_ref().filter(|_| boolean(p, "fromGesture") == Some(true)).map(|i| i.doc.clone()).unwrap_or_else(|| ds.doc.clone());
+    let layout = crate::selection_spacing::selection_spacing(&base, &ids);
+    let mut offsets = std::collections::BTreeMap::<NodeId, (Option<f64>, Option<f64>)>::new();
+    let mut any = false;
+    for (key, axis, vertical) in [("horizontal", &layout.horizontal, false), ("vertical", &layout.vertical, true)] {
+        if get(p, key).is_none() {
+            continue;
+        }
+        let value = req_num("arrange.spacing", p, key)?;
+        if value.abs() > 1_000_000.0 {
+            return Err(bad("arrange.spacing", "spacing out of range"));
+        }
+        let axis = axis.as_ref().ok_or_else(|| bad("arrange.spacing", "selection has no spacing on this axis"))?;
+        any = true;
+        for (id, delta) in axis.offsets(value) {
+            if !delta.is_finite() {
+                return Err(bad("arrange.spacing", "non-finite spacing result"));
+            }
+            let pair = offsets.entry(id).or_default();
+            if vertical {
+                pair.1 = Some(delta);
+            } else {
+                pair.0 = Some(delta);
+            }
+        }
+    }
+    if !any {
+        return Err(bad("arrange.spacing", "pass horizontal or vertical spacing"));
+    }
+    let doc = s.doc_mut()?;
+    let mut moves = Vec::new();
+    for (id, (dx, dy)) in offsets {
+        let (Some(before), Some(now)) = (base.world_bounds(id), doc.world_bounds(id)) else { continue };
+        let (dx, dy) = (dx.map_or(0.0, |d| before.x0 + d - now.x0), dy.map_or(0.0, |d| before.y0 + d - now.y0));
+        if !dx.is_finite() || !dy.is_finite() {
+            return Err(bad("arrange.spacing", "non-finite spacing result"));
+        }
+        moves.push((id, dx, dy));
+    }
+    for (id, dx, dy) in moves {
+        move_world(doc, id, dx, dy)?;
+    }
+    ok()
+}

crates/engine/src/cmd/component.rs

@@ -68,7 +68,7 @@ pub fn specs() -> Vec<CommandSpec> {
             let cmd = "instance.create";
             let c = req_id(cmd, p, "component")?;
             let page = s.page()?;
-            let parent = id(p, "parent").unwrap_or(page);
+            let parent = crate::params::opt_id(cmd, p, "parent")?.unwrap_or(page);
             let doc = s.doc_mut()?;
             let c = main_of(doc, c).ok_or_else(|| bad(cmd, "`component` must be a component or component set"))?;
             let (x, y) = match (num(p, "x"), num(p, "y")) {
@@ -678,8 +678,8 @@ fn push_changes(s: &mut Session, p: &Value) -> Result<Value> {
     if !doc.contains(component) {
         return Err(EngineError::Disabled(cmd.into(), "the main component was deleted (use component.restoreMain)".into()));
     }
-    // Copy every overridden layer's values to its source in the main (geometry, swaps, property
-    // values and slot content stay with the instance).
+    // Copy every overridden layer's values to its source in the main (geometry, resizing, swaps,
+    // property values and slot content stay with the instance).
     let mut pushed = 0;
     for d in doc.subtree(inst) {
         let Some(n) = doc.node(d).cloned() else { continue };
@@ -691,7 +691,7 @@ fn push_changes(s: &mut Session, p: &Value) -> Result<Value> {
         let groups: BTreeSet<String> = n
             .overrides
             .iter()
-            .filter(|g| !matches!(g.as_str(), "size" | "position" | "component" | "props" | SLOT) && !(d == inst && g.as_str() == "name"))
+            .filter(|g| !(matches!(g.as_str(), "size" | "resizing" | "position" | "component" | "props" | SLOT) || d == inst && g.as_str() == "name"))
             .cloned()
             .collect();
         for g in &groups {

crates/engine/src/cmd/create.rs

@@ -7,7 +7,7 @@ use serde_json::{Value, json};
 
 use super::{CommandSpec, ok};
 use crate::params::*;
-use crate::{EngineError, Result, Session, bad, spec};
+use crate::{Result, Session, bad, spec};
 
 /// Frame presets shown by the Frame tool (category, name, width, height).
 pub const FRAME_PRESETS: &[(&str, &str, f64, f64)] = &[
@@ -73,9 +73,13 @@ pub fn specs() -> Vec<CommandSpec> {
         spec!("text.create", "Text", "{text, x, y, parent?, width? (fixed width wraps), props? (fontSize, fontFamily, …)}", true, |s, p| {
             create_kind(s, p, "text")
         }),
-        spec!("vector.create", "Vector", "{path (SVG path data) | points [[x,y],..], closed?, x?, y?, parent?, props?}", true, |s, p| create_kind(
-            s, p, "vector"
-        )),
+        spec!(
+            "vector.create",
+            "Vector",
+            "{path (SVG path data) | points [[x,y],..], closed?, x?, y?, width?, height? (scale the path; one keeps its proportion), parent?, props?}",
+            true,
+            |s, p| create_kind(s, p, "vector")
+        ),
         spec!(
             "image.place",
             "Place image",
@@ -162,12 +166,43 @@ pub fn parse_path_data(d: &str) -> Option<figcraft_geom::BezPath> {
     figcraft_geom::BezPath::from_svg(d).ok()
 }
 
+/// How much a vector's path is scaled to take the size asked for: with both sides, each scales
+/// independently (as resizing a vector does); with one, the other keeps its proportion. A size on
+/// an axis the geometry has none of is an error unless it is 0 (a line's height), and a size of 0
+/// or less on an axis it has is refused rather than flattening it.
+fn vector_scale(width: Option<f64>, height: Option<f64>, bw: f64, bh: f64, what: &str) -> std::result::Result<(f64, f64), String> {
+    let fit = |asked: Option<f64>, have: f64, axis: &str| match asked {
+        None => Ok(1.0),
+        Some(a) if have <= 1e-9 => {
+            if a == 0.0 {
+                Ok(1.0)
+            } else {
+                Err(format!("`{axis}` can't size {what} with no {} extent", if axis == "width" { "horizontal" } else { "vertical" }))
+            }
+        }
+        Some(a) if a > 0.0 && (a / have).is_finite() => Ok(a / have),
+        Some(_) => Err(format!("`{axis}` must be a positive, finite size: 0 or less would flatten {what}")),
+    };
+    Ok(match (width, height) {
+        (Some(_), Some(_)) => (fit(width, bw, "width")?, fit(height, bh, "height")?),
+        (Some(_), None) => {
+            let s = fit(width, bw, "width")?;
+            (s, s)
+        }
+        (None, Some(_)) => {
+            let s = fit(height, bh, "height")?;
+            (s, s)
+        }
+        (None, None) => (1.0, 1.0),
+    })
+}
+
 pub fn create(s: &mut Session, p: &Value) -> Result<Value> {
     let cmd = "node.create";
     let t = string(p, "type").ok_or_else(|| bad(cmd, "`type` is required"))?;
     let (mut kind, base) = kind_for(&t).ok_or_else(|| bad(cmd, format!("unknown type `{t}`")))?;
     let page = s.page()?;
-    let parent = id(p, "parent").unwrap_or(page);
+    let parent = crate::params::opt_id(cmd, p, "parent")?.unwrap_or(page);
     let doc = s.doc()?;
     let pn = doc.get(parent)?;
     if !pn.kind.is_container() {
@@ -187,20 +222,32 @@ pub fn create(s: &mut Session, p: &Value) -> Result<Value> {
         "Section" => (num_or(p, "width", 400.0), num_or(p, "height", 300.0)),
         _ => (num_or(p, "width", 100.0), num_or(p, "height", 100.0)),
     };
-    // Vectors: path data or points define the shape and its box.
+    // Vectors: path data or points define the shape and its box. `width`/`height`, when asked
+    // for, scale the geometry: both sides independently, one side proportionally.
     let mut offset = (0.0, 0.0);
+    let asked = (num(p, "width"), num(p, "height"));
     if let NodeKind::Vector { network } = &mut kind {
         if let Some(d) = string(p, "path") {
             let mut path = parse_path_data(&d).ok_or_else(|| bad(cmd, "`path` is not valid SVG path data"))?;
             use figcraft_geom::Shape;
             let bb = path.bounding_box();
+            if bb.width() <= 1e-9 && bb.height() <= 1e-9 {
+                return Err(bad(cmd, "`path` draws nothing: a vector needs a visible line or area"));
+            }
             path.apply_affine(figcraft_geom::Affine::translate((-bb.x0, -bb.y0)));
+            let (sx, sy) = vector_scale(asked.0, asked.1, bb.width(), bb.height(), "a path").map_err(|e| bad(cmd, e))?;
+            if sx != 1.0 || sy != 1.0 {
+                path.apply_affine(figcraft_geom::Affine::scale_non_uniform(sx, sy));
+            }
             *network = VectorNetwork::from_path(&path);
+            if network.segments.is_empty() {
+                return Err(bad(cmd, "`path` draws nothing: a vector needs a visible line or area"));
+            }
             if boolean(p, "closed") == Some(false) {
                 network.regions.clear();
             }
-            w = bb.width();
-            h = bb.height();
+            w = bb.width() * sx;
+            h = bb.height() * sy;
             offset = (bb.x0, bb.y0);
         } else if let Some(Value::Array(pts)) = get(p, "points") {
             let pts: Vec<Point> = pts.iter().filter_map(|v| Some(Point::new(f64_of(v.get(0)?)?, f64_of(v.get(1)?)?))).collect();
@@ -208,10 +255,14 @@ pub fn create(s: &mut Session, p: &Value) -> Result<Value> {
                 return Err(bad(cmd, "`points` needs at least two [x, y] pairs"));
             }
             let bb = figcraft_geom::points_bounds(pts.iter().copied()).unwrap_or_default();
-            let local: Vec<Point> = pts.iter().map(|q| Point::new(q.x - bb.x0, q.y - bb.y0)).collect();
+            if bb.width() <= 1e-9 && bb.height() <= 1e-9 {
+                return Err(bad(cmd, "`points` draws nothing: a vector needs a visible line or area"));
+            }
+            let (sx, sy) = vector_scale(asked.0, asked.1, bb.width(), bb.height(), "a point set").map_err(|e| bad(cmd, e))?;
+            let local: Vec<Point> = pts.iter().map(|q| Point::new((q.x - bb.x0) * sx, (q.y - bb.y0) * sy)).collect();
             *network = VectorNetwork::from_points(&local, boolean(p, "closed").unwrap_or(false));
-            w = bb.width();
-            h = bb.height();
+            w = bb.width() * sx;
+            h = bb.height() * sy;
             offset = (bb.x0, bb.y0);
         }
     }
@@ -255,7 +306,7 @@ pub fn create(s: &mut Session, p: &Value) -> Result<Value> {
         node.width = tw;
         node.height = th;
     }
-    let index = num(p, "index").map(|i| i.max(0.0) as usize);
+    let index = crate::params::opt_index(cmd, p, "index")?;
     doc.insert(node, parent, index)?;
     if let Some(Value::Object(props)) = get(p, "props") {
         super::props::apply(cmd, doc, nid, props)?;
@@ -313,12 +364,12 @@ fn free_spot(s: &Session, w: f64, h: f64) -> Result<(f64, f64)> {
 
 #[cfg(not(target_arch = "wasm32"))]
 fn read_path(path: &str) -> Result<Vec<u8>> {
-    std::fs::read(path).map_err(|e| EngineError::Other(format!("{path}: {e}")))
+    crate::file_access::read(path)
 }
 
 #[cfg(target_arch = "wasm32")]
 fn read_path(path: &str) -> Result<Vec<u8>> {
-    Err(EngineError::Other(format!("{path}: files can't be read in the browser")))
+    Err(crate::EngineError::Other(format!("{path}: files can't be read in the browser")))
 }
 
 /// Place an image as a rectangle with an image fill (Figma's image layer).
@@ -340,7 +391,7 @@ pub fn place_image(s: &mut Session, p: &Value) -> Result<Value> {
         _ => ImageScaleMode::Fill,
     };
     let page = s.page()?;
-    let parent = id(p, "parent").unwrap_or(page);
+    let parent = crate::params::opt_id(cmd, p, "parent")?.unwrap_or(page);
     let ds = s.ds_mut()?;
     let doc = ds.doc_mut();
     let (hash, iw, ih) = figcraft_format::add_image(doc, bytes).map_err(|e| bad(cmd, e.to_string()))?;

crates/engine/src/cmd/edit.rs

@@ -503,9 +503,14 @@ fn bump_name(n: &str) -> String {
 }
 
 /// The copied form of the selection.
-pub fn copy_to_clipboard(s: &mut Session, ids: &[NodeId]) -> Result<()> {
+pub fn copy_to_clipboard(s: &mut Session, cmd: &str, ids: &[NodeId]) -> Result<()> {
     let ds = s.ds()?;
-    let (nodes, images, bounds) = copied(&ds.doc, ids);
+    // Pages are not layers: they can't be pasted anywhere.
+    let layers: Vec<NodeId> = ids.iter().copied().filter(|i| !ds.doc.node(*i).is_some_and(Node::is_page)).collect();
+    if layers.is_empty() && !ids.is_empty() {
+        return Err(EngineError::Disabled(cmd.into(), "pages can't be copied; use page.duplicate".into()));
+    }
+    let (nodes, images, bounds) = copied(&ds.doc, &layers);
     let (source, source_path, uid) = (ds.doc.clone(), ds.path.clone(), ds.uid);
     s.clipboard.source = Some(source);
     s.clipboard.source_path = source_path;
@@ -598,14 +603,16 @@ fn paste_design_layers(s: &mut Session, p: &Value) -> Result<Value> {
 
 fn copy(s: &mut Session, p: &Value) -> Result<Value> {
     let ids = req_targets("edit.copy", s, p)?;
-    copy_to_clipboard(s, &ids)?;
+    copy_to_clipboard(s, "edit.copy", &ids)?;
     Ok(json!({"copied": s.clipboard.nodes.len()}))
 }
 
 fn cut(s: &mut Session, p: &Value) -> Result<Value> {
     let ids = req_targets("edit.cut", s, p)?;
-    copy_to_clipboard(s, &ids)?;
-    delete(s, &json!({"ids": ids}))
+    copy_to_clipboard(s, "edit.cut", &ids)?;
+    let doc = s.doc()?;
+    let layers: Vec<NodeId> = ids.into_iter().filter(|i| !doc.node(*i).is_some_and(Node::is_page)).collect();
+    delete(s, &json!({"ids": layers}))
 }
 
 /// Paste the clipboard under `parent` with the copied top-left moved to `at` (page coords).
@@ -1149,9 +1156,34 @@ fn set(s: &mut Session, p: &Value) -> Result<Value> {
             .collect(),
         None => Vec::new(),
     };
+    let mut warnings = font_style_warnings(&s.ds()?.doc, &ids, &props);
+    // Auto layout keys go to the layers that can have auto layout; with none among the targets,
+    // the first refuses them (`props::layout_mut`).
+    let layout_keys: Vec<&str> = props.keys().map(String::as_str).filter(|k| super::props::LAYOUT_KEYS.contains(k)).collect();
+    let mut without_layout = props.clone();
+    let mut skipped = BTreeSet::new();
+    if !layout_keys.is_empty() {
+        let doc = &s.ds()?.doc;
+        let frame_like = |i: &NodeId| doc.node(*i).is_some_and(|n| n.kind.is_frame_like());
+        if ids.iter().any(frame_like) {
+            skipped = ids.iter().copied().filter(|i| !frame_like(i)).collect();
+            without_layout.retain(|k, _| !layout_keys.contains(&k.as_str()));
+        }
+        if !skipped.is_empty() {
+            let names: Vec<String> =
+                skipped.iter().take(10).filter_map(|i| doc.node(*i)).map(|n| format!("{} “{}” ({})", n.id, n.name, n.kind.type_name())).collect();
+            let more = if skipped.len() > names.len() { format!(" and {} more", skipped.len() - names.len()) } else { String::new() };
+            warnings.push(format!(
+                "{} skipped on {}{more}: only frames, components and instances have auto layout",
+                layout_keys.iter().map(|k| format!("`{k}`")).collect::<Vec<_>>().join(", "),
+                names.join(", ")
+            ));
+        }
+    }
     let doc = s.doc_mut()?;
     for i in ids {
-        super::props::apply("node.set", doc, i, &props)?;
+        let props = if skipped.contains(&i) { &without_layout } else { &props };
+        super::props::apply("node.set", doc, i, props)?;
     }
     if let Some(o) = pivot {
         for (i, q) in pinned {
@@ -1161,7 +1193,43 @@ fn set(s: &mut Session, p: &Value) -> Result<Value> {
             }
         }
     }
-    ok()
+    if warnings.is_empty() { ok() } else { Ok(json!({"ok": true, "warnings": warnings})) }
+}
+
+/// A `fontStyle` draws in the family's face nearest to it, as a text layer resolves it. When that
+/// face has another weight or slant than the name asks for ("Black" on a family whose heaviest is
+/// Bold), say which face it is. Families that aren't installed, and names that match a style or a
+/// named instance (spelled any way: "SemiBold", "Semi Bold"), say nothing.
+fn font_style_warnings(doc: &figcraft_doc::Document, ids: &[NodeId], props: &serde_json::Map<String, Value>) -> Vec<String> {
+    let Some(style) = props.get("fontStyle").and_then(Value::as_str) else { return Vec::new() };
+    let mut families: Vec<String> = match props.get("fontFamily").and_then(Value::as_str) {
+        Some(f) => vec![f.to_string()],
+        None => ids
+            .iter()
+            .filter_map(|i| doc.node(*i))
+            .filter_map(|n| n.kind.text())
+            .flat_map(|t| t.spans().into_iter().map(|(_, _, st)| st.font_family.clone()).collect::<Vec<_>>())
+            .collect(),
+    };
+    families.sort();
+    families.dedup();
+    let norm = |s: &str| s.to_lowercase().replace([' ', '-', '_'], "");
+    let (want_w, want_i) = (i32::from(figcraft_doc::style_weight(style)), style.to_lowercase().contains("italic"));
+    families
+        .into_iter()
+        .filter_map(|family| {
+            let styles = figcraft_text::family_styles(&family);
+            if styles.is_empty() || styles.iter().any(|x| norm(x) == norm(style)) {
+                return None;
+            }
+            let face = figcraft_text::find_face(&family, style).filter(|f| f.family.eq_ignore_ascii_case(&family))?;
+            let w = face.axis("wght").map_or(i32::from(face.weight), |a| a.clamp(f64::from(want_w)).round() as i32);
+            if face.instance(style).is_some() || (w == want_w && face.italic == want_i) {
+                return None;
+            }
+            Some(format!("{family} has no `{style}` style: it draws in {}, the nearest (it has: {})", face.style, styles.join(", ")))
+        })
+        .collect()
 }
 
 /// `stroke.widthProfile`: a preset or points (through `node.set`'s `widthProfile`, so instances
@@ -1240,7 +1308,7 @@ fn paint_list(s: &mut Session, p: &Value, fills: bool, add: bool) -> Result<Valu
 fn paint_set(s: &mut Session, p: &Value, fills: bool) -> Result<Value> {
     let cmd = if fills { "fill.set" } else { "stroke.set" };
     let ids = req_targets(cmd, s, p)?;
-    let idx = num(p, "index").map(|x| x.max(0.0) as usize);
+    let idx = opt_index(cmd, p, "index")?;
     let new_paint = match get(p, "paint") {
         Some(v) => Some(paint_of(v).ok_or_else(|| bad(cmd, "invalid paint"))?),
         None => None,
@@ -1288,7 +1356,7 @@ fn pattern_fill(s: &mut Session, p: &Value) -> Result<Value> {
     const CMD: &str = "fill.pattern";
     let src = req_id(CMD, p, "source")?;
     let doc = s.doc()?;
-    if !doc.node(src).is_some_and(|n| !n.is_page()) {
+    if doc.node(src).is_none_or(|n| n.is_page()) {
         return Err(bad(CMD, "`source` must be a layer"));
     }
     if req_targets(CMD, s, p)?.iter().any(|t| doc.is_ancestor(*t, src)) {

crates/engine/src/cmd/file.rs

@@ -435,7 +435,7 @@ pub(crate) fn recovered(path: &str) -> Result<DocState> {
 
 #[cfg(not(target_arch = "wasm32"))]
 fn read(path: &str) -> Result<Vec<u8>> {
-    std::fs::read(path).map_err(|e| EngineError::Other(format!("{path}: {e}")))
+    crate::file_access::read(path)
 }
 
 #[cfg(target_arch = "wasm32")]
@@ -445,11 +445,7 @@ fn read(path: &str) -> Result<Vec<u8>> {
 
 /// The bytes of file `path`, refused when it's larger than `max`.
 pub(crate) fn read_capped(path: &str, max: u64) -> Result<Vec<u8>> {
-    let meta = std::fs::metadata(path).map_err(|e| EngineError::Other(format!("{path}: {e}")))?;
-    if !meta.is_file() || meta.len() > max {
-        return Err(EngineError::Other(format!("{path}: not a file of at most {max} bytes")));
-    }
-    read(path)
+    crate::file_access::read_capped(path, max)
 }
 
 /// Write `bytes` to `path` through a uniquely named, exclusively created staging file and one
@@ -457,7 +453,7 @@ pub(crate) fn read_capped(path: &str, max: u64) -> Result<Vec<u8>> {
 /// truncates `path`, and no file or symlink at a staging name is ever written through.
 #[cfg(not(target_arch = "wasm32"))]
 pub(crate) fn write(path: &str, bytes: &[u8]) -> Result<()> {
-    figcraft_format::write_file_atomic(std::path::Path::new(path), bytes).map_err(|e| EngineError::Other(format!("{path}: {e}")))
+    crate::file_access::write(path, bytes)
 }
 
 #[cfg(target_arch = "wasm32")]
@@ -552,6 +548,7 @@ pub(crate) fn load_fig(bytes: &[u8], name: &str) -> Option<Result<figcraft_forma
 /// Link imported instances to their mains (layer sources, overrides found by comparing values),
 /// innermost first so outer instances settle last.
 fn link_instances(doc: &mut Document) {
+    super::styles::unfold_imported_bound_alpha(doc);
     crate::style_vars::after_load(doc);
     super::styles::apply_paint_bindings_on_load(doc);
     let mut insts: Vec<(usize, NodeId)> =
@@ -577,11 +574,9 @@ fn rest_images(path: &str) -> impl Fn(&str) -> Option<Vec<u8>> {
             return None;
         }
         let dir = dir.as_ref()?;
-        ["", ".png", ".jpg", ".jpeg", ".gif", ".webp"].iter().find_map(|e| {
-            let p = dir.join(format!("{r}{e}"));
-            let meta = std::fs::metadata(&p).ok()?;
-            if meta.is_file() && meta.len() <= MAX_IMAGE_FILE { std::fs::read(&p).ok() } else { None }
-        })
+        ["", ".png", ".jpg", ".jpeg", ".gif", ".webp"]
+            .iter()
+            .find_map(|e| crate::file_access::read_capped(dir.join(format!("{r}{e}")), MAX_IMAGE_FILE).ok())
     }
 }
 
@@ -604,11 +599,7 @@ fn sibling_variables(path: &str) -> Option<Value> {
     let file = std::path::Path::new(path);
     let dir = file.parent()?;
     [format!("{}.variables.json", file_stem(path)), "variables.json".to_string()].iter().map(|n| dir.join(n)).filter(|c| c != file).find_map(|c| {
-        let meta = std::fs::metadata(&c).ok()?;
-        if !meta.is_file() || meta.len() > MAX_VARIABLES_FILE {
-            return None;
-        }
-        let v: Value = serde_json::from_slice(&std::fs::read(&c).ok()?).ok()?;
+        let v: Value = serde_json::from_slice(&crate::file_access::read_capped(c, MAX_VARIABLES_FILE).ok()?).ok()?;
         figcraft_format::rest::is_variables_json(&v).then_some(v)
     })
 }
@@ -646,20 +637,29 @@ fn remember(s: &mut Session, path: &str) {
 }
 
 fn open_recent(s: &mut Session, p: &Value) -> Result<Value> {
+    use crate::file_access::{Access, allow, allowed};
     const CMD: &str = "file.openRecent";
+    // Confined to automation roots, the recent files outside them are never listed, opened, removed
+    // or named: `index` counts the files listed.
+    let listed = |r: &String| allowed(r, Access::Read);
     if p.get("clear").and_then(Value::as_bool) == Some(true) {
-        s.prefs.recent_files.clear();
+        s.prefs.recent_files.retain(|r| !listed(r));
     }
     if let Some(gone) = string(p, "remove") {
-        s.prefs.recent_files.retain(|r| *r != gone);
+        s.prefs.recent_files.retain(|r| *r != gone || !listed(r));
     }
     let path = match (string(p, "path"), num(p, "index")) {
-        (Some(path), _) => Some(path),
-        (None, Some(i)) => Some(s.prefs.recent_files.get(i.max(0.0) as usize).cloned().ok_or_else(|| bad(CMD, "no such recent file"))?),
+        (Some(path), _) => {
+            allow(&path, Access::Read)?;
+            Some(path)
+        }
+        (None, Some(i)) => {
+            Some(s.prefs.recent_files.iter().filter(|r| listed(r)).nth(i.max(0.0) as usize).cloned().ok_or_else(|| bad(CMD, "no such recent file"))?)
+        }
         _ => None,
     };
     if let Some(path) = path {
-        if !std::path::Path::new(&path).exists() {
+        if !crate::file_access::exists(&path) {
             s.prefs.recent_files.retain(|r| *r != path);
             return Err(bad(CMD, format!("{path} no longer exists")));
         }
@@ -669,9 +669,10 @@ fn open_recent(s: &mut Session, p: &Value) -> Result<Value> {
         .prefs
         .recent_files
         .iter()
+        .filter(|r| listed(r))
         .map(|r| {
             let name = std::path::Path::new(r).file_name().map_or_else(|| r.clone(), |f| f.to_string_lossy().into_owned());
-            json!({"path": r, "name": name, "exists": std::path::Path::new(r).exists()})
+            json!({"path": r, "name": name, "exists": crate::file_access::exists(r)})
         })
         .collect();
     Ok(json!({"files": files}))
@@ -1183,7 +1184,7 @@ fn export_layers(s: &mut Session, p: &Value) -> Result<Value> {
                 let path = std::path::Path::new(d).join(&job.file);
                 // A layer name with slashes exports into folders.
                 if let Some(parent) = path.parent() {
-                    let _ = std::fs::create_dir_all(parent);
+                    let _ = crate::file_access::create_dir_all(parent);
                 }
                 let path = path.to_string_lossy().to_string();
                 write(&path, &bytes)?;

crates/engine/src/cmd/mod.rs

@@ -71,6 +71,7 @@ fn registry() -> &'static Registry {
         list.extend(create::specs());
         list.extend(edit::specs());
         list.extend(lists::specs());
+        list.extend(crate::selection_colors::specs());
         list.extend(arrange::specs());
         list.extend(structure::specs());
         list.extend(section::specs());
@@ -79,6 +80,7 @@ fn registry() -> &'static Registry {
         list.extend(page::specs());
         list.extend(view::specs());
         list.extend(text::specs());
+        list.extend(crate::fonts::specs());
         list.extend(styles::specs());
         list.extend(image::specs());
         list.extend(variables::specs());

crates/engine/src/cmd/props.rs

@@ -265,6 +265,56 @@ fn ensure_layout(n: &mut Node) -> &mut AutoLayout {
     n.layout.get_or_insert_with(|| AutoLayout { padding: [0.0; 4], gap: 0.0, ..Default::default() })
 }
 
+/// The keys that set a frame's auto layout (through [`layout_mut`]).
+pub const LAYOUT_KEYS: &[&str] = &[
+    "gap",
+    "itemSpacing",
+    "columnGap",
+    "crossGap",
+    "counterAxisSpacing",
+    "rowGap",
+    "padding",
+    "paddingTop",
+    "paddingRight",
+    "paddingBottom",
+    "paddingLeft",
+    "paddingHorizontal",
+    "paddingVertical",
+    "mainAlign",
+    "primaryAxisAlignItems",
+    "crossAlign",
+    "counterAxisAlignItems",
+    "contentAlign",
+    "counterAxisAlignContent",
+    "wrap",
+    "gridColumns",
+    "gridRows",
+    "strokesIncluded",
+    "reverseZ",
+    "columnTracks",
+    "gridColumnTracks",
+    "rowTracks",
+    "gridRowTracks",
+];
+
+/// The auto layout of a frame-like node, created when it has none yet. Other nodes can't hold an
+/// auto layout: an auto layout key on them is refused, not stored where nothing reads it
+/// (`node.set` on several layers skips them instead, see `edit::set`).
+fn layout_mut<'a>(cmd: &str, k: &str, n: &'a mut Node) -> Result<&'a mut AutoLayout> {
+    if !n.kind.is_frame_like() {
+        return Err(bad(
+            cmd,
+            format!(
+                "`{k}` is an auto layout property, and layer {} “{}” is a {} (only frames, components and instances have auto layout)",
+                n.id,
+                n.name,
+                n.kind.type_name()
+            ),
+        ));
+    }
+    Ok(ensure_layout(n))
+}
+
 /// Apply a property map to one node. `x`/`y` are relative to the parent.
 pub fn apply(cmd: &str, doc: &mut Document, id: NodeId, props: &Map<String, Value>) -> Result<()> {
     let mut unknown = Vec::new();
@@ -452,56 +502,56 @@ pub fn apply(cmd: &str, doc: &mut Document, id: NodeId, props: &Map<String, Valu
                 }
             }
             "gap" | "itemSpacing" | "columnGap" => {
-                ensure_layout(doc.get_mut(id)?).gap = f64_of(v).ok_or_else(|| bad(cmd, format!("`{k}` must be a number")))?
+                layout_mut(cmd, k, doc.get_mut(id)?)?.gap = f64_of(v).ok_or_else(|| bad(cmd, format!("`{k}` must be a number")))?
             }
             "crossGap" | "counterAxisSpacing" | "rowGap" => {
-                ensure_layout(doc.get_mut(id)?).cross_gap = f64_of(v).ok_or_else(|| bad(cmd, format!("`{k}` must be a number")))?
+                layout_mut(cmd, k, doc.get_mut(id)?)?.cross_gap = f64_of(v).ok_or_else(|| bad(cmd, format!("`{k}` must be a number")))?
             }
             "padding" => {
                 let p = four(v).ok_or_else(|| bad(cmd, "padding: n or [t,r,b,l]"))?;
-                ensure_layout(doc.get_mut(id)?).padding = p.map(|x| x.max(0.0));
+                layout_mut(cmd, k, doc.get_mut(id)?)?.padding = p.map(|x| x.max(0.0));
             }
             "paddingTop" | "paddingRight" | "paddingBottom" | "paddingLeft" => {
                 let i = ["paddingTop", "paddingRight", "paddingBottom", "paddingLeft"].iter().position(|x| *x == k).unwrap_or(0);
                 let val = f64_of(v).ok_or_else(|| bad(cmd, format!("`{k}` must be a number")))?.max(0.0);
-                if let Some(slot) = ensure_layout(doc.get_mut(id)?).padding.get_mut(i) {
+                if let Some(slot) = layout_mut(cmd, k, doc.get_mut(id)?)?.padding.get_mut(i) {
                     *slot = val;
                 }
             }
             "paddingHorizontal" => {
                 let val = f64_of(v).unwrap_or(0.0).max(0.0);
-                let l = ensure_layout(doc.get_mut(id)?);
+                let l = layout_mut(cmd, k, doc.get_mut(id)?)?;
                 l.padding[1] = val;
                 l.padding[3] = val;
             }
             "paddingVertical" => {
                 let val = f64_of(v).unwrap_or(0.0).max(0.0);
-                let l = ensure_layout(doc.get_mut(id)?);
+                let l = layout_mut(cmd, k, doc.get_mut(id)?)?;
                 l.padding[0] = val;
                 l.padding[2] = val;
             }
             "mainAlign" | "primaryAxisAlignItems" => {
-                ensure_layout(doc.get_mut(id)?).main_align =
+                layout_mut(cmd, k, doc.get_mut(id)?)?.main_align =
                     enum_of(v).ok_or_else(|| bad(cmd, "mainAlign: min|center|max|spaceBetween|spaceAround|spaceEvenly"))?
             }
             "crossAlign" | "counterAxisAlignItems" => {
-                ensure_layout(doc.get_mut(id)?).cross_align = enum_of(v).ok_or_else(|| bad(cmd, "crossAlign: min|center|max|baseline"))?
+                layout_mut(cmd, k, doc.get_mut(id)?)?.cross_align = enum_of(v).ok_or_else(|| bad(cmd, "crossAlign: min|center|max|baseline"))?
             }
             "contentAlign" | "counterAxisAlignContent" => {
-                ensure_layout(doc.get_mut(id)?).content_align = enum_of(v).ok_or_else(|| bad(cmd, "contentAlign: auto|spaceBetween"))?
+                layout_mut(cmd, k, doc.get_mut(id)?)?.content_align = enum_of(v).ok_or_else(|| bad(cmd, "contentAlign: auto|spaceBetween"))?
             }
-            "wrap" => ensure_layout(doc.get_mut(id)?).wrap = v.as_bool().unwrap_or(false),
+            "wrap" => layout_mut(cmd, k, doc.get_mut(id)?)?.wrap = v.as_bool().unwrap_or(false),
             "gridColumns" | "gridRows" => {
                 let count = f64_of(v).ok_or_else(|| bad(cmd, format!("`{k}` must be a number")))?.clamp(1.0, 1000.0) as u32;
-                let l = ensure_layout(doc.get_mut(id)?);
+                let l = layout_mut(cmd, k, doc.get_mut(id)?)?;
                 // Tracks past the new count go away (new tracks are 1fr).
                 let (n, tracks) =
                     if k == "gridColumns" { (&mut l.grid_columns, &mut l.column_tracks) } else { (&mut l.grid_rows, &mut l.row_tracks) };
                 *n = count;
                 tracks.truncate(count as usize);
             }
-            "strokesIncluded" => ensure_layout(doc.get_mut(id)?).strokes_included = v.as_bool().unwrap_or(false),
-            "reverseZ" => ensure_layout(doc.get_mut(id)?).reverse_z = v.as_bool().unwrap_or(false),
+            "strokesIncluded" => layout_mut(cmd, k, doc.get_mut(id)?)?.strokes_included = v.as_bool().unwrap_or(false),
+            "reverseZ" => layout_mut(cmd, k, doc.get_mut(id)?)?.reverse_z = v.as_bool().unwrap_or(false),
             "sizingH" | "layoutSizingHorizontal" => {
                 let s = sizing(v).ok_or_else(|| bad(cmd, "sizing: fixed|hug|fill"))?;
                 set_sizing(cmd, doc, id, s, true)?;
@@ -533,7 +583,7 @@ pub fn apply(cmd: &str, doc: &mut Document, id: NodeId, props: &Map<String, Valu
             "columnTracks" | "gridColumnTracks" | "rowTracks" | "gridRowTracks" => {
                 let a = v.as_array().ok_or_else(|| bad(cmd, format!("`{k}` must be an array of tracks")))?;
                 let tracks = a.iter().map(track_of).collect::<Option<Vec<_>>>().ok_or_else(|| bad(cmd, TRACK_HELP))?;
-                let l = ensure_layout(doc.get_mut(id)?);
+                let l = layout_mut(cmd, k, doc.get_mut(id)?)?;
                 if k.contains("olumn") {
                     l.grid_columns = (tracks.len() as u32).clamp(1, 1000);
                     l.column_tracks = tracks;
@@ -725,10 +775,15 @@ pub fn apply(cmd: &str, doc: &mut Document, id: NodeId, props: &Map<String, Valu
                     for (field, var) in o {
                         match var.as_str() {
                             Some(vid) => {
+                                if n.bound.get(field).map(String::as_str) != Some(vid) {
+                                    crate::cmd::styles::rebind_paint_alpha(&mut n.fills, &mut n.strokes, field, true);
+                                }
                                 n.bound.insert(field.clone(), vid.to_string());
                             }
                             None => {
-                                n.bound.remove(field);
+                                if n.bound.remove(field).is_some() {
+                                    crate::cmd::styles::rebind_paint_alpha(&mut n.fills, &mut n.strokes, field, false);
+                                }
                             }
                         }
                     }
@@ -783,12 +838,14 @@ pub fn apply(cmd: &str, doc: &mut Document, id: NodeId, props: &Map<String, Valu
     if !unknown.is_empty() {
         return Err(bad(cmd, format!("unknown properties: {} (known: {KEYS})", unknown.join(", "))));
     }
-    // Inside an instance, record which property groups were overridden (an instance's own export
-    // settings and interactions are its own, not overrides).
+    // Inside an instance, record which property groups were overridden (an instance's own
+    // resizing, export settings and interactions are its own, not overrides).
     let own_root = matches!(doc.get(id)?.kind, NodeKind::Instance { .. }) && !crate::components::inside_instance(doc, id);
     let n = doc.get_mut(id)?;
     if n.source.is_some() {
-        for g in props.keys().map(|k| override_group(k)).filter(|g| *g != "other" && !(own_root && matches!(*g, "exports" | "interactions"))) {
+        for g in
+            props.keys().map(|k| override_group(k)).filter(|g| *g != "other" && !(own_root && matches!(*g, "resizing" | "exports" | "interactions")))
+        {
             n.overrides.insert(g.to_string());
         }
     }
@@ -810,7 +867,8 @@ pub fn override_group(k: &str) -> &'static str {
         "features" | "fontFeatures" | "openTypeFeatures" | "listStyle" | "indentation" | "listSpacing" | "maxLines" | "variationSettings"
         | "hangingPunctuation" | "hangingList" => "textStyle",
         "cornerRadius" | "cornerSmoothing" | "topLeftRadius" | "topRightRadius" | "bottomRightRadius" | "bottomLeftRadius" => "corners",
-        "width" | "height" | "w" | "h" | "sizingH" | "sizingV" => "size",
+        "width" | "height" | "w" | "h" => "size",
+        "sizingH" | "sizingV" | "layoutSizingHorizontal" | "layoutSizingVertical" | "minWidth" | "maxWidth" | "minHeight" | "maxHeight" => "resizing",
         "gap" | "itemSpacing" | "columnGap" | "crossGap" | "counterAxisSpacing" | "rowGap" => "gap",
         "padding" | "paddingTop" | "paddingRight" | "paddingBottom" | "paddingLeft" | "paddingHorizontal" | "paddingVertical" => "padding",
         "mainAlign" | "primaryAxisAlignItems" | "crossAlign" | "counterAxisAlignItems" | "contentAlign" | "counterAxisAlignContent" => "alignment",

crates/engine/src/cmd/structure.rs

@@ -544,11 +544,16 @@ fn layout_add(s: &mut Session, p: &Value) -> Result<Value> {
             let pb = doc.node(*b).map(|n| figcraft_geom::transform_rect_bbox(n.transform, n.local_rect())).unwrap_or_default();
             if vertical { pa.y0.total_cmp(&pb.y0) } else { pa.x0.total_cmp(&pb.x0) }
         });
+        let empty = doc.node(*f).is_some_and(|n| n.children.iter().filter_map(|c| doc.node(*c)).all(|c| !c.visible || c.child_layout.absolute));
         let n = doc.get_mut(*f)?;
         n.children = kids;
         n.layout = Some(al);
-        n.child_layout.sizing_h = Sizing::Hug;
-        n.child_layout.sizing_v = Sizing::Hug;
+        if !all_frames || !empty {
+            // A frame wrapped around the selection hugs it; an existing frame with no flow
+            // children keeps its size instead of collapsing to its padding.
+            n.child_layout.sizing_h = Sizing::Hug;
+            n.child_layout.sizing_v = Sizing::Hug;
+        }
     }
     s.set_selection(targets.clone());
     Ok(json!({"ids": targets}))

crates/engine/src/cmd/styles.rs

@@ -458,10 +458,19 @@ fn bind_style(s: &mut Session, p: &Value) -> Result<Value> {
     match var {
         Some((_, kind)) if kind != want => return Err(bad(cmd, format!("`{field}` takes a {} variable, not a {} one", want.id(), kind.id()))),
         Some((id, _)) => {
+            if style.bound.get(&key) != Some(&id)
+                && let StyleKind::Paint { paints } = &mut style.kind
+            {
+                rebind_paint_alpha(paints, &mut [], &key, true);
+            }
             style.bound.insert(key, id);
         }
         None => {
-            style.bound.remove(&key);
+            if style.bound.remove(&key).is_some()
+                && let StyleKind::Paint { paints } = &mut style.kind
+            {
+                rebind_paint_alpha(paints, &mut [], &key, false);
+            }
         }
     }
     // The style takes its default-mode value, and each layer using it its own.
@@ -770,16 +779,41 @@ pub fn bind(s: &mut Session, p: &Value) -> Result<Value> {
         let n = doc.get_mut(i)?;
         match &vid {
             Some(v) => {
+                if n.bound.get(&field) != Some(v) {
+                    rebind_paint_alpha(&mut n.fills, &mut n.strokes, &field, true);
+                }
                 n.bound.insert(field.clone(), v.clone());
             }
             None => {
-                n.bound.remove(&field);
+                if n.bound.remove(&field).is_some() {
+                    rebind_paint_alpha(&mut n.fills, &mut n.strokes, &field, false);
+                }
             }
         }
     }
     ok()
 }
 
+/// A colour variable bound to a solid paint owns its whole colour, alpha included. Binding restarts
+/// the opacity (which holds the alpha a typed colour had, see `Paint::solid`) at 1, so the
+/// variable's alpha applies once; unbinding moves the colour's alpha back into the opacity, where a
+/// typed colour keeps it. An opacity set while bound multiplies on top and stays.
+pub(crate) fn rebind_paint_alpha(fills: &mut [Paint], strokes: &mut [Paint], field: &str, bind: bool) {
+    use super::lists::{BoundList, list_binding};
+    let Some((list, i, "color")) = list_binding(field) else { return };
+    let paints = match list {
+        BoundList::Fills => fills,
+        BoundList::Strokes => strokes,
+        _ => return,
+    };
+    if let Some(p) = paints.get_mut(i)
+        && let PaintKind::Solid { color } = &mut p.kind
+    {
+        p.opacity = if bind { 1.0 } else { p.opacity * color.a };
+        color.a = 1.0;
+    }
+}
+
 /// `variable.setMode`: choose a collection's mode on frames (the page when none are given).
 pub fn set_mode(s: &mut Session, p: &Value) -> Result<Value> {
     let cmd = "variable.setMode";
@@ -916,6 +950,49 @@ pub fn apply_bindings_to(doc: &mut Document, only: Option<&std::collections::BTr
     apply_bindings_matching(doc, only, |_| true);
 }
 
+/// Imported files (`.fig`, REST) keep a solid paint's alpha in its opacity, a bound paint's too,
+/// while the bound colour brings its own alpha: take the variable's alpha back out of the opacity
+/// (styles' paints and layers') before the bindings are first resolved, so it applies once.
+pub(crate) fn unfold_imported_bound_alpha(doc: &mut Document) {
+    use super::lists::{BoundList, list_binding};
+    fn alphas(vars: &Variables, bound: &BTreeMap<String, VariableId>, modes: &BTreeMap<CollectionId, ModeId>) -> Vec<(BoundList, usize, f32)> {
+        let found = bound.iter().filter_map(|(field, var)| match (list_binding(field)?, vars.resolve(var, modes)?) {
+            ((list @ (BoundList::Fills | BoundList::Strokes), i, "color"), VariableValue::Color(c)) if c.a > 0.0 && c.a < 1.0 => Some((list, i, c.a)),
+            _ => None,
+        });
+        found.collect()
+    }
+    fn unfold(p: Option<&mut Paint>, a: f32) {
+        if let Some(p) = p
+            && matches!(p.kind, PaintKind::Solid { .. })
+        {
+            p.opacity = (p.opacity / a).min(1.0);
+        }
+    }
+    let pending = doc.take_dirty();
+    for i in 0..doc.styles.len() {
+        let found = doc.styles.get(i).map(|s| alphas(&doc.variables, &s.bound, &BTreeMap::new())).unwrap_or_default();
+        if let Some(StyleKind::Paint { paints }) = doc.styles.get_mut(i).filter(|_| !found.is_empty()).map(|s| &mut s.kind) {
+            for (_, j, a) in found {
+                unfold(paints.get_mut(j), a);
+            }
+        }
+    }
+    let ids: Vec<NodeId> = doc.nodes().filter(|n| !n.bound.is_empty()).map(|n| n.id).collect();
+    for id in ids {
+        let found = doc.node(id).map(|n| alphas(&doc.variables, &n.bound, &doc.modes_for(id))).unwrap_or_default();
+        if found.is_empty() {
+            continue;
+        }
+        let Ok(n) = doc.get_mut(id) else { continue };
+        for (list, j, a) in found {
+            unfold(if list == BoundList::Fills { n.fills.get_mut(j) } else { n.strokes.get_mut(j) }, a);
+        }
+    }
+    doc.take_dirty();
+    doc.mark_dirty(pending);
+}
+
 /// Settle imported paint colours before the document is first shown. Other bindings can affect
 /// layout or component structure, which must be resolved through the normal edit pipeline.
 pub(crate) fn apply_paint_bindings_on_load(doc: &mut Document) {
@@ -1104,7 +1181,6 @@ pub fn document_colors(doc: &Document, page: NodeId) -> Vec<(Color, usize)> {
         stack.extend(n.children.iter().copied());
         for paint in n.fills.iter().chain(n.strokes.iter()).filter(|p| p.visible) {
             if let Some(c) = paint.solid_color() {
-                let c = c.with_alpha(c.a * paint.opacity);
                 counts.entry(c.to_rgba8()).or_insert((c, 0)).1 += 1;
             }
         }

crates/engine/src/cmd/variables.rs

@@ -288,7 +288,11 @@ pub(crate) fn forget_variables(doc: &mut Document, gone: &BTreeSet<VariableId>)
     doc.variables.variables.retain(|v| !gone.contains(&v.id));
     let users: Vec<NodeId> = doc.nodes().filter(|n| n.bound.values().any(|v| gone.contains(v))).map(|n| n.id).collect();
     for id in users {
-        doc.get_mut(id)?.bound.retain(|_, v| !gone.contains(v));
+        let n = doc.get_mut(id)?;
+        for (field, _) in n.bound.iter().filter(|(_, v)| gone.contains(*v)) {
+            super::styles::rebind_paint_alpha(&mut n.fills, &mut n.strokes, field, false);
+        }
+        n.bound.retain(|_, v| !gone.contains(v));
     }
     Ok(())
 }

crates/engine/src/cmd/variables_io.rs

@@ -25,7 +25,7 @@ pub fn specs() -> Vec<CommandSpec> {
         spec!(
             "variable.import",
             "Import variables",
-            "{variables (the local variables JSON, as variable.export writes it: an object, JSON text or a path)}  collections join this file's collection of the same name (values by mode name; new modes and variables are added, a variable of another type is skipped), others are added  → {collections (added), variables (added), updated, warnings}",
+            "{variables (the local variables JSON, as variable.export writes it: an object, JSON text or a path; `variableCollections` and `variables` under `meta` or at the top level)}  collections join this file's collection of the same name (values by mode name; new modes and variables are added, a variable of another type is skipped), others are added  → {collections (added), variables (added), updated, warnings (also when it holds no variables, or fewer than its collections list)}",
             true,
             import
         ),

crates/engine/src/cmd/view.rs

@@ -19,30 +19,58 @@ fn flag(s: &mut Session, p: &Value, f: fn(&mut ViewState) -> &mut bool) -> Resul
     Ok(json!({"on": *slot}))
 }
 
+/// One of a view's on/off settings.
+type Slot = fn(&mut ViewState) -> &mut bool;
+
+/// The View menu's on/off toggles (Pixel preview, with its scale, has its own command), and
+/// whether the preferences keep each: files opened or made later start with the kept ones. Outline
+/// modes and the sRGB soft-proof stay with their file, so a new file never opens in one.
+const TOGGLES: &[(&str, Slot, bool)] = &[
+    ("view.pixelGrid", |v| &mut v.pixel_grid, true),
+    ("view.layoutGrids", |v| &mut v.layout_grids, true),
+    ("view.rulers", |v| &mut v.rulers, true),
+    ("view.slices", |v| &mut v.show_slices, true),
+    ("view.comments", |v| &mut v.comments, true),
+    ("view.multiplayerCursors", |v| &mut v.multiplayer_cursors, true),
+    ("view.outlines", |v| &mut v.outlines, false),
+    ("view.outlinesSelection", |v| &mut v.outlines_selection, false),
+    ("view.outlinesHiddenLayers", |v| &mut v.outline_hidden, true),
+    ("view.outlinesObjectBounds", |v| &mut v.outline_bounds, true),
+    ("view.maskOutlines", |v| &mut v.mask_outlines, true),
+    ("view.frameOutlines", |v| &mut v.frame_outlines, true),
+    ("view.proofSrgb", |v| &mut v.proof_srgb, false),
+    ("view.snapGeometry", |v| &mut v.snap_geometry, true),
+    ("view.snapObjects", |v| &mut v.snap_objects, true),
+    ("view.snapPixel", |v| &mut v.snap_pixel, true),
+];
+
+/// View toggle `id`: the file's view changes, and the preferences remember a kept one.
+fn toggle(s: &mut Session, p: &Value, id: &str) -> Result<Value> {
+    let Some(&(_, f, keep)) = TOGGLES.iter().find(|(k, ..)| *k == id) else { return Err(bad(id, "not a View toggle")) };
+    let r = flag(s, p, f)?;
+    if keep && let Some(on) = r.get("on").and_then(Value::as_bool) {
+        s.prefs.view.insert(id.to_string(), on);
+    }
+    Ok(r)
+}
+
+/// Set `v`'s View toggles to the ones the preferences keep (the others stay as they are).
+pub(crate) fn apply_kept(prefs: &crate::Prefs, v: &mut ViewState) {
+    for (id, f, _) in TOGGLES.iter().filter(|t| t.2) {
+        if let Some(on) = prefs.view.get(*id) {
+            *f(v) = *on;
+        }
+    }
+}
+
 /// Whether the View menu's toggle `id` is on (the menus show a check mark); `None` for a command
 /// that isn't one.
 pub fn checked(s: &Session, id: &str) -> Option<bool> {
-    let v = &s.ds().ok()?.view;
-    Some(match id {
-        "view.pixelGrid" => v.pixel_grid,
-        "view.layoutGrids" => v.layout_grids,
-        "view.rulers" => v.rulers,
-        "view.slices" => v.show_slices,
-        "view.comments" => v.comments,
-        "view.multiplayerCursors" => v.multiplayer_cursors,
-        "view.outlines" => v.outlines,
-        "view.outlinesSelection" => v.outlines_selection,
-        "view.outlinesHiddenLayers" => v.outline_hidden,
-        "view.outlinesObjectBounds" => v.outline_bounds,
-        "view.maskOutlines" => v.mask_outlines,
-        "view.pixelPreview" => v.pixel_preview,
-        "view.frameOutlines" => v.frame_outlines,
-        "view.proofSrgb" => v.proof_srgb,
-        "view.snapGeometry" => v.snap_geometry,
-        "view.snapObjects" => v.snap_objects,
-        "view.snapPixel" => v.snap_pixel,
-        _ => return None,
-    })
+    let mut v = s.ds().ok()?.view.clone();
+    if id == "view.pixelPreview" {
+        return Some(v.pixel_preview);
+    }
+    TOGGLES.iter().find(|(k, ..)| *k == id).map(|(_, f, _)| *f(&mut v))
 }
 
 /// Pixel preview: toggles, or turns on at a resolution of 1x or 2x.
@@ -235,46 +263,46 @@ pub fn specs() -> Vec<CommandSpec> {
         spec!("view.nextFrame", "Zoom to next frame", "{}", false, |s, _| zoom_frame(s, 1)),
         spec!("view.prevPage", "Previous page", "{}", false, |s, _| page_step(s, -1)),
         spec!("view.nextPage", "Next page", "{}", false, |s, _| page_step(s, 1)),
-        spec!("view.pixelGrid", "Pixel grid", "{on?}", false, |s, p| flag(s, p, |v| &mut v.pixel_grid)),
-        spec!("view.layoutGrids", "Layout grids", "{on?}", false, |s, p| flag(s, p, |v| &mut v.layout_grids)),
-        spec!("view.rulers", "Rulers", "{on?}", false, |s, p| flag(s, p, |v| &mut v.rulers)),
-        spec!("view.slices", "Slices", "{on?}", false, |s, p| flag(s, p, |v| &mut v.show_slices)),
-        spec!("view.comments", "Comments", "{on?}", false, |s, p| flag(s, p, |v| &mut v.comments)),
+        spec!("view.pixelGrid", "Pixel grid", "{on?}", false, |s, p| toggle(s, p, "view.pixelGrid")),
+        spec!("view.layoutGrids", "Layout grids", "{on?}", false, |s, p| toggle(s, p, "view.layoutGrids")),
+        spec!("view.rulers", "Rulers", "{on?}", false, |s, p| toggle(s, p, "view.rulers")),
+        spec!("view.slices", "Slices", "{on?}", false, |s, p| toggle(s, p, "view.slices")),
+        spec!("view.comments", "Comments", "{on?}", false, |s, p| toggle(s, p, "view.comments")),
         spec!("view.multiplayerCursors", "Multiplayer cursors", "{on?}  others' cursors in a live session", false, |s, p| {
-            flag(s, p, |v| &mut v.multiplayer_cursors)
+            toggle(s, p, "view.multiplayerCursors")
         }),
         spec!("view.pan", "Pan the view", "{dx, dy (arrow-key steps, e.g. 1 or -1), big? (ten times as far, like Shift)}", false, pan),
-        spec!("view.outlines", "Outlines", "{on?}", false, |s, p| flag(s, p, |v| &mut v.outlines)),
+        spec!("view.outlines", "Outlines", "{on?}", false, |s, p| toggle(s, p, "view.outlines")),
         spec!("view.outlinesSelection", "Outlines for selection", "{on?}  outline mode for the selected layers only", false, |s, p| {
-            flag(s, p, |v| &mut v.outlines_selection)
+            toggle(s, p, "view.outlinesSelection")
         }),
         spec!(
             "view.outlinesHiddenLayers",
             "Include hidden layers in outlines",
             "{on?}  outline mode (and outlines for the selection) outlines hidden layers too; they can be clicked there",
             false,
-            |s, p| { flag(s, p, |v| &mut v.outline_hidden) }
+            |s, p| { toggle(s, p, "view.outlinesHiddenLayers") }
         ),
         spec!(
             "view.outlinesObjectBounds",
             "Include object bounds in outlines",
             "{on?}  outline mode also draws each layer's box (groups, text, vectors); a click on a box's edge picks its layer",
             false,
-            |s, p| { flag(s, p, |v| &mut v.outline_bounds) }
+            |s, p| { toggle(s, p, "view.outlinesObjectBounds") }
         ),
-        spec!("view.maskOutlines", "Mask outlines", "{on?}", false, |s, p| flag(s, p, |v| &mut v.mask_outlines)),
+        spec!("view.maskOutlines", "Mask outlines", "{on?}", false, |s, p| toggle(s, p, "view.maskOutlines")),
         spec!("view.pixelPreview", "Pixel preview", "{on?, scale? (1|2: rendered pixels per page pixel; turns it on)}", false, pixel_preview),
-        spec!("view.frameOutlines", "Frame outlines", "{on?}", false, |s, p| flag(s, p, |v| &mut v.frame_outlines)),
+        spec!("view.frameOutlines", "Frame outlines", "{on?}", false, |s, p| toggle(s, p, "view.frameOutlines")),
         spec!(
             "view.proofSrgb",
             "Soft-proof sRGB",
             "{on?}  mark the colours of a Display P3 file that sRGB screens and files can't show",
             false,
-            |s, p| { flag(s, p, |v| &mut v.proof_srgb) }
+            |s, p| { toggle(s, p, "view.proofSrgb") }
         ),
-        spec!("view.snapGeometry", "Snap to geometry", "{on?}", false, |s, p| flag(s, p, |v| &mut v.snap_geometry)),
-        spec!("view.snapObjects", "Snap to objects", "{on?}", false, |s, p| flag(s, p, |v| &mut v.snap_objects)),
-        spec!("view.snapPixel", "Snap to pixel grid", "{on?}", false, |s, p| flag(s, p, |v| &mut v.snap_pixel)),
+        spec!("view.snapGeometry", "Snap to geometry", "{on?}", false, |s, p| toggle(s, p, "view.snapGeometry")),
+        spec!("view.snapObjects", "Snap to objects", "{on?}", false, |s, p| toggle(s, p, "view.snapObjects")),
+        spec!("view.snapPixel", "Snap to pixel grid", "{on?}", false, |s, p| toggle(s, p, "view.snapPixel")),
         spec!("view.toggleUi", "Show/Hide UI", "{on?}", false, |s, p| flag(s, p, |v| &mut v.ui_hidden)),
         spec!("view.fullscreen", "Full screen", "{on?}  the window fills the screen (the desktop app; a no-op headless)", false, |s, p| {
             s.request_ui("window.fullscreen", json!({"on": boolean(p, "on")}));

crates/engine/src/codegen.rs

@@ -256,7 +256,7 @@ fn stroke_color(n: &Node) -> Option<Color> {
     if !n.has_visible_stroke() {
         return None;
     }
-    n.strokes.iter().filter(|p| p.visible).find_map(|p| p.solid_color().map(|c| c.with_alpha(c.a * p.opacity)))
+    n.strokes.iter().filter(|p| p.visible).find_map(|p| p.solid_color())
 }
 
 fn drop_shadow(n: &Node) -> Option<&Shadow> {

crates/engine/src/components.rs

@@ -11,12 +11,12 @@
 //! Override groups: `fills`, `strokes`, `effects`, `opacity`, `visible`, `name`, `corners`,
 //! `characters`, `textStyle` (font, size, spacing, resizing, …), `padding`, `gap` and `alignment`
 //! (of auto layout: its direction and other settings are the main's), `grids`, `exports`,
-//! `interactions`, `component` (a swapped nested instance), `props` (property values of a nested
-//! instance) and `slot` (a slot holding the instance's own content). An instance's own export
-//! settings and interactions are its own, like its place. `size` and `position` overrides of
-//! layers inside an instance are still read and kept, but new ones are refused
-//! ([`check_override_edit`]): those layers take their geometry, constraints and resizing from the
-//! main; the instance itself resizes.
+//! `interactions`, `size` and `resizing` (hug, fill or fixed, with min and max sizes) of layers
+//! inside an instance, `component` (a swapped nested instance), `props` (property values of a
+//! nested instance) and `slot` (a slot holding the instance's own content). An instance's own
+//! export settings, interactions and resizing are its own, like its place. `position`
+//! overrides of layers inside an instance are still read and kept, but new ones are refused
+//! ([`check_override_edit`]): those layers take their place and constraints from the main.
 //!
 //! Switching variants keeps an override where the layer's name path matches and the two variants
 //! agreed on that property (text layers keep all of theirs); swapping from the Assets panel keeps
@@ -58,6 +58,7 @@ pub const OVERRIDE_GROUPS: &[&str] = &[
     "exports",
     "interactions",
     "size",
+    "resizing",
     "position",
     "component",
     "props",
@@ -388,11 +389,14 @@ pub(crate) fn copy_group(from: &Node, to: &mut Node, g: &str) {
         "size" => {
             to.width = from.width;
             to.height = from.height;
-            to.child_layout = from.child_layout.clone();
             if let (NodeKind::Text(a), NodeKind::Text(b)) = (&from.kind, &mut to.kind) {
                 b.auto_resize = a.auto_resize;
             }
         }
+        "resizing" => {
+            let (a, b) = (&from.child_layout, &mut to.child_layout);
+            (b.sizing_h, b.sizing_v, b.min_w, b.max_w, b.min_h, b.max_h) = (a.sizing_h, a.sizing_v, a.min_w, a.max_w, a.min_h, a.max_h);
+        }
         "position" => to.transform = from.transform,
         "component" => {
             if let (NodeKind::Instance { component: a, .. }, NodeKind::Instance { component: b, .. }) = (&from.kind, &mut to.kind) {
@@ -773,6 +777,15 @@ fn sync_instance_depth(doc: &mut Document, inst: NodeId, depth: usize, spare: BT
     for s in &src {
         let Some(nid) = map.get(s).copied() else { continue };
         let Some(o) = old.get(&nid) else { continue };
+        // A frame that kept the size its own resizing gave it: its layers (copied at their main
+        // layers' places) follow their constraints from its main layer's size.
+        if o.overrides.contains("resizing")
+            && !o.overrides.contains("size")
+            && doc.node(nid).is_some_and(|n| n.kind.is_frame_like() && n.layout.is_none())
+            && let Some((mw, mh)) = doc.node(*s).map(|m| (m.width, m.height))
+        {
+            figcraft_layout::apply_constraints(doc, nid, mw, mh);
+        }
         if !o.overrides.contains("size") && !o.overrides.contains("position") {
             continue;
         }
@@ -985,6 +998,9 @@ pub fn diff_groups(a: &Node, b: &Node) -> Vec<&'static str> {
     if (a.width - b.width).abs() > 1e-6 || (a.height - b.height).abs() > 1e-6 {
         out.push("size");
     }
+    if resizing(a) != resizing(b) {
+        out.push("resizing");
+    }
     if a.transform != b.transform {
         out.push("position");
     }
@@ -1027,6 +1043,12 @@ pub fn diff_groups(a: &Node, b: &Node) -> Vec<&'static str> {
     out
 }
 
+/// The `resizing` group of a layer: how it sizes on each axis, and its min and max sizes.
+fn resizing(n: &Node) -> (Sizing, Sizing, [Option<f64>; 4]) {
+    let c = &n.child_layout;
+    (c.sizing_h, c.sizing_v, [c.min_w, c.max_w, c.min_h, c.max_h])
+}
+
 /// Whether two texts differ in anything but their characters (the `textStyle` group).
 fn text_style_differs(x: &TextData, y: &TextData) -> bool {
     x.style != y.style
@@ -1107,9 +1129,10 @@ pub fn sync_after_edit(doc: &mut Document, before: &Document, changed: &[NodeId]
         }
         let raw = diff_groups(b, n);
         let mut groups = raw.clone();
-        // An instance's own place, export settings and interactions are its own, not overrides.
+        // An instance's own place, resizing, export settings and interactions are its own, not
+        // overrides.
         if top_root {
-            groups.retain(|g| !matches!(*g, "component" | "props" | "position" | "exports" | "interactions"));
+            groups.retain(|g| !matches!(*g, "component" | "props" | "position" | "resizing" | "exports" | "interactions"));
         }
         if groups.iter().any(|g| matches!(*g, "size" | "position")) {
             groups.retain(|g| !matches!(*g, "size" | "position") || !geometry_derived(doc, before, id, g));
@@ -1414,7 +1437,7 @@ fn patch_structure(doc: &mut Document, before: &Document, seeds: &[NodeId]) -> b
 fn child_follows_main(doc: &Document, parent: NodeId, absolute: bool) -> bool {
     let Some(p) = doc.node(parent) else { return false };
     let constrains = p.layout.is_none() || absolute;
-    let resized = p.overrides.contains("size")
+    let resized = sized_own(p)
         || match &p.kind {
             NodeKind::Instance { component, .. } => {
                 doc.node(*component).is_none_or(|m| (m.width - p.width).abs() > 1e-9 || (m.height - p.height).abs() > 1e-9)
@@ -1475,7 +1498,7 @@ fn patch_copies(doc: &mut Document, seeds: &[(NodeId, Vec<&'static str>)]) -> bo
             let gs: Vec<&'static str> = groups
                 .iter()
                 .copied()
-                .filter(|g| !cn.overrides.contains(*g) && !(root && matches!(*g, "visible" | "name" | "position" | "exports" | "interactions")))
+                .filter(|g| !(cn.overrides.contains(*g) || root && matches!(*g, "visible" | "name" | "position" | "exports" | "interactions")))
                 .collect();
             if gs.is_empty() {
                 continue;
@@ -1518,7 +1541,7 @@ fn follows_main_geometry(doc: &Document, id: NodeId) -> bool {
     chain.windows(2).all(|w| {
         let (Some(below), Some(a)) = (w.first().and_then(|i| doc.node(*i)), w.get(1).and_then(|i| doc.node(*i))) else { return false };
         let constrains = a.layout.is_none() || below.child_layout.absolute;
-        if a.overrides.contains("size") && constrains {
+        if sized_own(a) && constrains {
             return false;
         }
         match &a.kind {
@@ -1530,6 +1553,12 @@ fn follows_main_geometry(doc: &Document, id: NodeId) -> bool {
     })
 }
 
+/// Whether a layer inside an instance overrides its size or resizing: it may not have its main
+/// layer's size, so the layers in it can't take their main layers' places as they are.
+fn sized_own(n: &Node) -> bool {
+    n.overrides.contains("size") || n.overrides.contains("resizing")
+}
+
 /// Rebuild every instance of `comps` (and of the components that hold those instances, and so on
 /// outwards), each outermost instance once, inner components first.
 fn rebuild_instances(doc: &mut Document, comps: &BTreeSet<NodeId>) {
@@ -1665,10 +1694,9 @@ pub fn check_override_edit(before: &Document, after: &Document) -> Result<(), St
 
 /// What about layer `id` an edit from `before` to `after` changed that only its main can: the
 /// auto layout of an instance or a layer in one but its padding, gap and alignment, or the
-/// position (rotation too), size, constraints or resizing of a layer inside an instance (the
-/// instance itself resizes, and its layers follow; text whose box follows its content still
-/// does). `None` when the edit is fine, also when the main changed the same way in this edit (a
-/// library update).
+/// position (rotation too), constraints or place in auto layout (absolute, grid cell) of a layer
+/// inside an instance (its size and resizing are overrides). `None` when the edit is fine, also
+/// when the main changed the same way in this edit (a library update).
 pub fn refused_override(before: &Document, after: &Document, id: NodeId) -> Option<&'static str> {
     let (n, b) = (after.node(id)?, before.node(id)?);
     if after.is_remote(id) || n.source != b.source || owning_instance(before, id).is_none() || owning_instance(after, id).is_none() {
@@ -1684,8 +1712,12 @@ pub fn refused_override(before: &Document, after: &Document, id: NodeId) -> Opti
             l
         })
     };
-    let size = |x: &Node| (x.width, x.height);
-    let resized = |x: &Node, y: &Node| (x.width - y.width).abs() > 1e-6 || (x.height - y.height).abs() > 1e-6;
+    // Child layout settings other than the resizing ones.
+    let placing = |x: &Node| {
+        let mut c = x.child_layout.clone();
+        (c.sizing_h, c.sizing_v, c.min_w, c.max_w, c.min_h, c.max_h) = (Sizing::Fixed, Sizing::Fixed, None, None, None, None);
+        c
+    };
     if mode(n) != mode(b) && mode(ma) == mode(mb) {
         return Some("The auto layout direction");
     }
@@ -1698,14 +1730,11 @@ pub fn refused_override(before: &Document, after: &Document, id: NodeId) -> Opti
     if n.transform != b.transform && ma.transform == mb.transform && !geometry_derived(after, before, id, "position") {
         return Some("A layer's position");
     }
-    if resized(n, b) && size(ma) == size(mb) && !geometry_derived(after, before, id, "size") {
-        return Some("A layer's size");
-    }
     if n.constraints != b.constraints && ma.constraints == mb.constraints {
         return Some("A layer's constraints");
     }
-    if n.child_layout != b.child_layout && ma.child_layout == mb.child_layout {
-        return Some("A layer's resizing");
+    if placing(n) != placing(b) && placing(ma) == placing(mb) {
+        return Some("A layer's place in auto layout");
     }
     None
 }
@@ -1923,6 +1952,7 @@ pub fn rebase_instance(doc: &mut Document, inst: NodeId) {
             let mut groups: Vec<String> = value_groups(m, n)
                 .into_iter()
                 .filter(|g| !matches!(g.as_str(), "name" | "exports" | "interactions") && !from_variables.contains(&g.as_str()))
+                .filter(|g| placed_source.is_some() || g != "resizing")
                 .collect();
             let named = if placed_source.is_some() { n.name != m.name } else { n.name != default_instance_name(doc, component) };
             if named {
@@ -1946,7 +1976,8 @@ pub fn rebase_instance(doc: &mut Document, inst: NodeId) {
     }
     if let Some(n) = doc.node_mut(inst) {
         n.source = root_base;
-        n.overrides.retain(|g| !matches!(g.as_str(), "component" | "props" | "position"));
+        // A top-level instance's resizing is its own (a nested one's overrides its main layer's).
+        n.overrides.retain(|g| !matches!(g.as_str(), "component" | "props" | "position") && (placed_source.is_some() || g != "resizing"));
         n.overrides.extend(root_groups);
     }
 }

crates/engine/src/components_behaviour_tests.rs

@@ -316,14 +316,6 @@ fn what_instances_cannot_override_is_refused() {
         ("nudge a layer", "transform.nudge", json!({"ids": ["$"], "dx": 1, "dy": 0}), Layer::Bg, "position"),
         ("rotate a layer", "node.set", json!({"id": "$", "props": {"rotation": 15}}), Layer::Bg, "position and rotation come with the layer's place"),
         ("flip a layer", "object.flipH", json!({"ids": ["$"]}), Layer::Bg, "position"),
-        (
-            "resize a layer",
-            "node.set",
-            json!({"id": "$", "props": {"width": 50}}),
-            Layer::Bg,
-            "not among the overridable properties; the instance resizes",
-        ),
-        ("resize a text box", "node.set", json!({"id": "$", "props": {"width": 150}}), Layer::Title, "\"the bounds of any text layers\""),
         (
             "change constraints",
             "node.set",
@@ -331,13 +323,6 @@ fn what_instances_cannot_override_is_refused() {
             Layer::Bg,
             "\"any constraints applied to the layers\"",
         ),
-        (
-            "make a layer fill its auto layout",
-            "node.set",
-            json!({"id": "$", "props": {"sizingH": "fill"}}),
-            Layer::Chip,
-            "resizing comes with the layer's size",
-        ),
         (
             "take a layer out of auto layout",
             "node.set",

crates/engine/src/components_tests.rs

@@ -67,8 +67,6 @@ fn overrides_survive_main_edits() {
     ex(&mut s, "node.set", json!({"id": ibg, "props": {"effects": [{"type": "dropShadow"}]}}));
     ex(&mut s, "text.set", json!({"id": ititle, "characters": "Overridden"}));
     ex(&mut s, "node.set", json!({"id": idot, "props": {"visible": false}}));
-    // A layer inside an instance keeps its main's size (the instance itself resizes).
-    assert!(s.execute("node.set", &json!({"id": idot, "props": {"width": 30}})).is_err());
     let ov = node(&s, ibg).overrides;
     for g in ["fills", "strokes", "effects", "name"] {
         assert!(ov.contains(g), "{g} in {ov:?}");

crates/engine/src/cursor_tests.rs

@@ -202,15 +202,16 @@ fn an_edit_an_instance_refuses_shows_not_allowed_and_is_undone() {
     let before = s.doc().unwrap().world_bounds(inner).unwrap();
     assert_eq!((before.x0, before.y0, before.x1, before.y1), (450.0, 50.0, 550.0, 150.0));
     ex(&mut s, "select.set", json!({"ids": [inner]}));
-    // Resizing it by its right edge: only the main component can.
-    assert!(close(resize(hover(&mut s, (550.0, 100.0), NONE)), 0.0), "the handle still shows its arrow");
+    // Resizing it by its right edge: a size of its own (an override).
+    assert!(close(resize(hover(&mut s, (550.0, 100.0), NONE)), 0.0), "the handle shows its arrow");
     s.pointer(&ev(PointerKind::Down, (550.0, 100.0), NONE)).unwrap();
     s.pointer(&ev(PointerKind::Move, (570.0, 100.0), NONE)).unwrap();
     s.pointer(&ev(PointerKind::Move, (600.0, 100.0), NONE)).unwrap();
-    assert_eq!(s.tool.overlay.cursor, Cursor::NotAllowed);
+    assert_ne!(s.tool.overlay.cursor, Cursor::NotAllowed);
     s.pointer(&ev(PointerKind::Up, (600.0, 100.0), NONE)).unwrap();
-    assert_eq!(s.doc().unwrap().world_bounds(inner).unwrap(), before, "the resize was undone");
-    // Moving it: refused too.
+    let before = s.doc().unwrap().world_bounds(inner).unwrap();
+    assert_eq!((before.x0, before.x1), (450.0, 600.0), "the resize stays");
+    // Moving it: only the main component can.
     s.pointer(&ev(PointerKind::Down, (500.0, 100.0), NONE)).unwrap();
     s.pointer(&ev(PointerKind::Move, (510.0, 110.0), NONE)).unwrap();
     s.pointer(&ev(PointerKind::Move, (520.0, 120.0), NONE)).unwrap();

crates/engine/src/doc_urls.rs

@@ -0,0 +1,48 @@
+//! Which URLs stored in a document may be handed to the browser or the system opener.
+//!
+//! A document can carry URLs that the app opens for whoever views it: a prototype's Open link
+//! action ([`crate::proto_run`]) and Dev Mode's dev resources ([`crate::dev_resources`]). Both end
+//! up at the platform's opener, so a document that someone else made chooses what that opener is
+//! asked to do. Only the schemes a browser would follow on a plain link are allowed:
+//!
+//! - `javascript:` runs script. In the web build the opener is `window.open`, which executes it in
+//!   the app's own origin, so a saved document becomes stored XSS.
+//! - `file:` and `smb:` reach the file system; on Windows a UNC host also sends credentials.
+//! - Windows hands `ms-…:` schemes to application handlers, and macOS and Linux hand unknown
+//!   schemes to whichever application registered them.
+//!
+//! The check is lexical and does no I/O. It is deliberately an allow-list: a deny-list of known
+//! dangerous schemes is outgrown by every new handler a platform adds.
+
+/// The schemes a URL stored in a document may use.
+const WEB_SCHEMES: [&str; 3] = ["http", "https", "mailto"];
+
+/// Whether `url`, stored in a document, may be opened.
+///
+/// Requires a scheme from [`WEB_SCHEMES`], compared ignoring ASCII case. A URL with no scheme is
+/// refused: the opener would resolve it against the app's own page on the web. Control characters
+/// are refused anywhere, because browsers ignore some of them inside a scheme (`java\tscript:`
+/// reaches a `javascript:` handler), and `http`/`https` must name a host.
+pub fn openable(url: &str) -> bool {
+    let url = url.trim();
+    if url.is_empty() || url.chars().any(char::is_control) {
+        return false;
+    }
+    let Some((scheme, rest)) = url.split_once(':') else { return false };
+    // An RFC 3986 scheme, so a stray colon in text cannot look like one.
+    let mut chars = scheme.chars();
+    if !chars.next().is_some_and(|c| c.is_ascii_alphabetic()) || !chars.all(|c| c.is_ascii_alphanumeric() || matches!(c, '+' | '-' | '.')) {
+        return false;
+    }
+    if !WEB_SCHEMES.iter().any(|s| scheme.eq_ignore_ascii_case(s)) {
+        return false;
+    }
+    if scheme.eq_ignore_ascii_case("mailto") {
+        // `mailto:` names an address.
+        return !rest.is_empty();
+    }
+    // `http` and `https` name a host, so the authority is required: `http:x` is not a web link,
+    // and `http:///p` has no host.
+    let Some(after) = rest.strip_prefix("//") else { return false };
+    !after.is_empty() && !after.starts_with('/')
+}

crates/engine/src/doc_urls_tests.rs

@@ -0,0 +1,87 @@
+//! A URL stored in a document reaches the browser or the system opener, so only the schemes a
+//! browser follows on a plain link are allowed ([`crate::doc_urls`]).
+
+use crate::doc_urls::openable;
+
+#[test]
+fn web_links_are_opened() {
+    for url in [
+        "http://example.com",
+        "https://example.com",
+        "https://example.com/a/b?c=d#e",
+        "HTTPS://EXAMPLE.COM",
+        "HtTp://example.com",
+        "mailto:[email protected]",
+        "mailto:[email protected]?subject=hi",
+        "  https://example.com  ",
+        "https://user:[email protected]:8443/p",
+    ] {
+        assert!(openable(url), "{url:?} should open");
+    }
+}
+
+#[test]
+fn script_and_handler_schemes_are_refused() {
+    for url in [
+        // Runs in the app's own origin on the web build: a saved document would be stored XSS.
+        "javascript:alert(1)",
+        "JavaScript:alert(1)",
+        "jAvAsCrIpT:alert(document.cookie)",
+        "vbscript:msgbox(1)",
+        "data:text/html,<script>alert(1)</script>",
+        "blob:https://example.com/x",
+        // Reach the file system; a UNC host also sends Windows credentials.
+        "file:///etc/passwd",
+        "file://attacker.example/share/x",
+        "smb://attacker.example/share/x",
+        "webdav://attacker.example/x",
+        // Windows application handlers.
+        "ms-msdt:/id PCWDiagnostic",
+        "ms-officecmd:x",
+        "search-ms:query=x",
+        "shell:startup",
+        // Anything else a platform may have registered.
+        "tel:+1234",
+        "sms:+1234",
+        "ssh://host",
+        "ftp://host/x",
+        "figcraft://join?host=127.0.0.1",
+        "zoommtg://zoom.us/join?x",
+        "view-source:https://example.com",
+        "jar:https://example.com/x!/y",
+    ] {
+        assert!(!openable(url), "{url:?} must be refused");
+    }
+}
+
+#[test]
+fn a_scheme_is_required_and_control_characters_are_refused() {
+    for url in [
+        // No scheme: the web opener would resolve these against the app's own page.
+        "",
+        "   ",
+        "example.com",
+        "/etc/passwd",
+        "//example.com",
+        "\\\\host\\share\\x",
+        "about",
+        // Browsers ignore some control characters inside a scheme, so a smuggled one must not
+        // leave `javascript` looking like an unknown scheme that we then refuse by luck.
+        "java\tscript:alert(1)",
+        "java\nscript:alert(1)",
+        "java\rscript:alert(1)",
+        "javascript\u{0}:alert(1)",
+        "https://example.com/\u{0}",
+        // A colon in ordinary text is not a scheme.
+        "see page 2: the diagram",
+        "1https://example.com",
+        // The allowed schemes still need their own part.
+        "mailto:",
+        "http:",
+        "http:example.com",
+        "http:///p",
+        "https://",
+    ] {
+        assert!(!openable(url), "{url:?} must be refused");
+    }
+}

crates/engine/src/duplicate_spacing_tests.rs

@@ -157,3 +157,49 @@ fn an_alt_drag_into_auto_layout_sets_no_step() {
     cmd_d(&mut s);
     assert_eq!(s.doc().unwrap().node(f).unwrap().children.len(), n + 1, "Duplicate still adds one to the flow");
 }
+
+/// Drag `from` by `by` with no modifier: moving the selection, not copying it.
+fn drag_move(s: &mut Session, from: (f64, f64), by: (f64, f64)) {
+    let ev = |kind, (x, y): (f64, f64)| PointerEvent::at(kind, x, y, 1.0);
+    s.pointer(&ev(PointerKind::Down, from)).unwrap();
+    for k in 1..=4 {
+        let t = f64::from(k) / 4.0;
+        s.pointer(&ev(PointerKind::Move, (from.0 + by.0 * t, from.1 + by.1 * t))).unwrap();
+    }
+    s.pointer(&ev(PointerKind::Up, (from.0 + by.0, from.1 + by.1))).unwrap();
+}
+
+/// The reported path (#567): Cmd+D, drag the copy with the mouse, Cmd+D again. The other tests
+/// here set the copy's position with `node.set` or Alt-drag it; dragging is how it is usually done,
+/// and the step is measured from where the copy ended up, whichever way it got there.
+#[test]
+fn duplicate_repeats_the_step_set_by_dragging_the_copy() {
+    let mut s = Session::new();
+    let a = rect(&mut s, 0.0, 0.0);
+    ex(&mut s, "select.set", json!({"ids": [a]}));
+    let c1 = cmd_d(&mut s);
+    assert_eq!(at(&s, c1), (0.0, 0.0), "the first copy lands in place");
+
+    drag_move(&mut s, (50.0, 50.0), (150.0, 20.0));
+    assert_eq!(at(&s, c1), (150.0, 20.0), "the drag moved the copy, it did not make another one");
+    assert_eq!(s.selection(), vec![c1], "and left it selected");
+    assert_eq!(at(&s, a), (0.0, 0.0), "the original stays");
+
+    let c2 = cmd_d(&mut s);
+    assert_eq!(at(&s, c2), (300.0, 40.0), "the next one as far again");
+    let c3 = cmd_d(&mut s);
+    assert_eq!(at(&s, c3), (450.0, 60.0), "and again");
+}
+
+/// And a step set with the arrow keys, which is how a small offset is usually made exact.
+#[test]
+fn duplicate_repeats_a_nudged_step() {
+    let mut s = Session::new();
+    let a = rect(&mut s, 0.0, 0.0);
+    ex(&mut s, "select.set", json!({"ids": [a]}));
+    let c1 = cmd_d(&mut s);
+    ex(&mut s, "transform.nudge", json!({"dx": 40, "dy": 0}));
+    assert_eq!(at(&s, c1), (40.0, 0.0));
+    let c2 = cmd_d(&mut s);
+    assert_eq!(at(&s, c2), (80.0, 0.0), "the nudge is the step");
+}

crates/engine/src/file_access.rs

@@ -0,0 +1,305 @@
+//! Automation roots (#715): the folders the files an agent's commands read and write must lie in.
+//!
+//! `figcraft-cli mcp --automation-read-root DIR --automation-write-root DIR` and the desktop app
+//! started with the same flags run their work [`confined`] to [`Roots`]: while a scope is active on
+//! the thread, every file the engine reads must lie inside a read or a write root and every file it
+//! writes inside a write root; anything else is an ordinary error. The engine reaches the file
+//! system only through this module (`crates/engine/clippy.toml` denies `std::fs` and friends
+//! anywhere else), so every command, present or future, is covered. Without a scope nothing changes.
+//!
+//! A path is made absolute against the working directory and resolved before it is compared: its
+//! links are followed (`std::fs::canonicalize`), and for a file that doesn't exist yet its nearest
+//! existing folder is resolved and the rest must be plain names. The comparison is by whole
+//! components (`/work2` is not inside `/work`), and the I/O uses the resolved path, so what was
+//! checked is what is opened.
+#![allow(clippy::disallowed_methods)]
+
+use std::cell::RefCell;
+use std::ffi::{OsStr, OsString};
+use std::path::{Component, Path, PathBuf};
+use std::sync::Arc;
+
+use crate::{EngineError, Result};
+
+/// What a command does with a file.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum Access {
+    Read,
+    Write,
+}
+
+/// The folders automation may read (read and write roots) and write (write roots), resolved.
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct Roots {
+    read: Vec<PathBuf>,
+    write: Vec<PathBuf>,
+}
+
+impl Roots {
+    /// Roots from the folders given (relative ones against the working directory). Each must be an
+    /// existing folder.
+    pub fn new(read: &[String], write: &[String]) -> std::result::Result<Self, String> {
+        let resolve = |flag: &str, dirs: &[String]| {
+            dirs.iter()
+                .map(|d| match std::fs::canonicalize(d) {
+                    Ok(p) if p.is_dir() => Ok(p),
+                    Ok(_) => Err(format!("{flag} {d}: not a folder")),
+                    Err(e) => Err(format!("{flag} {d}: {e}")),
+                })
+                .collect::<std::result::Result<Vec<_>, String>>()
+        };
+        Ok(Self { read: resolve("--automation-read-root", read)?, write: resolve("--automation-write-root", write)? })
+    }
+
+    /// The resolved path to use for `access` to `path`, or why it is refused.
+    pub fn check(&self, path: &Path, access: Access) -> std::result::Result<PathBuf, String> {
+        let asked = path.display();
+        let (roots, what) = match access {
+            Access::Read => ([self.read.as_slice(), self.write.as_slice()].concat(), "read"),
+            Access::Write => (self.write.clone(), "written"),
+        };
+        match resolve(path) {
+            Ok(resolved) if roots.iter().any(|r| resolved.starts_with(r)) => return Ok(resolved),
+            Ok(_) => {}
+            // Why a path can't be resolved says what exists there: only told for paths inside a root.
+            Err(why) if inside_as_far_as_it_exists(path, &roots) => return Err(format!("automation path rejected: {asked}: {why}")),
+            Err(_) => {}
+        }
+        if roots.is_empty() {
+            return Err(format!("automation path rejected: no folder may be {what} (no root for it was given): {asked}"));
+        }
+        let shown: Vec<String> = roots.iter().map(|r| shown(r)).collect();
+        Err(format!("automation path rejected: {asked} is outside the folders that may be {what}: {}", shown.join(", ")))
+    }
+
+    /// The folders as JSON, resolved: `{read: [every folder that may be read], write: [the write roots]}`.
+    pub fn to_json(&self) -> serde_json::Value {
+        let list = |v: &[PathBuf]| v.iter().map(|p| shown(p)).collect::<Vec<_>>();
+        serde_json::json!({"read": list(&[self.read.as_slice(), self.write.as_slice()].concat()), "write": list(&self.write)})
+    }
+}
+
+/// Whether `path` lies in one of `roots` once made absolute with its `.` and `..` taken by name and
+/// its longest leading part that exists resolved, so links on the way are followed as the roots'
+/// were (`/tmp/work/x` is inside root `/private/tmp/work`, a link out of a root leads out of it).
+fn inside_as_far_as_it_exists(path: &Path, roots: &[PathBuf]) -> bool {
+    let Ok(abs) = std::path::absolute(path) else { return false };
+    let mut lexical = PathBuf::new();
+    for c in abs.components() {
+        match c {
+            Component::ParentDir => {
+                lexical.pop();
+            }
+            Component::CurDir => {}
+            c => lexical.push(c),
+        }
+    }
+    let mut rest: Vec<&OsStr> = Vec::new();
+    let mut at = lexical.as_path();
+    let resolved = loop {
+        if let Ok(mut base) = std::fs::canonicalize(at) {
+            base.extend(rest.iter().rev());
+            break base;
+        }
+        let (Some(name), Some(parent)) = (at.file_name(), at.parent()) else { return false };
+        rest.push(name);
+        at = parent;
+    };
+    roots.iter().any(|r| resolved.starts_with(r))
+}
+
+/// Whether `path` lies in the app's own folder `folder`, both resolved (links and `..` followed);
+/// false when either can't be resolved.
+#[cfg_attr(target_arch = "wasm32", allow(dead_code))]
+pub(crate) fn within_app_folder(path: &Path, folder: &Path) -> bool {
+    matches!((std::fs::canonicalize(path), std::fs::canonicalize(folder)), (Ok(p), Ok(f)) if p.starts_with(&f))
+}
+
+/// `p` without Windows' `\\?\` prefix, for messages.
+fn shown(p: &Path) -> String {
+    let s = p.to_string_lossy();
+    match s.strip_prefix(r"\\?\UNC\") {
+        Some(unc) => format!(r"\\{unc}"),
+        None => s.strip_prefix(r"\\?\").unwrap_or(&s).to_string(),
+    }
+}
+
+/// `path` made absolute and resolved: links followed, and for a path that doesn't exist yet its
+/// nearest existing folder resolved with the rest appended (plain names only).
+fn resolve(path: &Path) -> std::result::Result<PathBuf, String> {
+    if path.as_os_str().is_empty() {
+        return Err("not a file path".into());
+    }
+    let abs = std::path::absolute(path).map_err(|e| e.to_string())?;
+    let mut rest: Vec<OsString> = Vec::new();
+    let mut at = abs.as_path();
+    loop {
+        match std::fs::canonicalize(at) {
+            Ok(mut base) => {
+                base.extend(rest.iter().rev());
+                return Ok(base);
+            }
+            Err(e) if e.kind() == std::io::ErrorKind::NotFound => {
+                // Writing through a link that leads nowhere would create its target, wherever it is.
+                if std::fs::symlink_metadata(at).is_ok() {
+                    return Err("a link that leads nowhere".into());
+                }
+                match at.components().next_back() {
+                    Some(Component::Normal(name)) => {
+                        plain_name(name)?;
+                        rest.push(name.to_os_string());
+                    }
+                    Some(Component::CurDir) => {}
+                    _ => return Err("`..` (or a drive) below a folder that doesn't exist".into()),
+                }
+                at = at.parent().ok_or("no existing folder")?;
+            }
+            Err(e) => return Err(e.to_string()),
+        }
+    }
+}
+
+/// A name for a file or folder that doesn't exist yet: on Windows no device (`CON`, `NUL`, `COM1`…)
+/// and no alternate data stream (`a:b`).
+fn plain_name(name: &OsStr) -> std::result::Result<(), String> {
+    if cfg!(windows) {
+        let n = name.to_string_lossy();
+        let stem = n.split('.').next().unwrap_or_default().trim_end().to_ascii_uppercase();
+        let device = matches!(stem.as_str(), "CON" | "PRN" | "AUX" | "NUL" | "CONIN$" | "CONOUT$")
+            || ((stem.starts_with("COM") || stem.starts_with("LPT"))
+                && stem.chars().count() == 4
+                && stem.chars().last().is_some_and(|c| c.is_ascii_digit() || matches!(c, '¹' | '²' | '³')));
+        if device || n.contains(':') {
+            return Err(format!("`{n}` is a device or stream name, not a file"));
+        }
+    }
+    Ok(())
+}
+
+thread_local! {
+    static ROOTS: RefCell<Option<Arc<Roots>>> = const { RefCell::new(None) };
+}
+
+/// Run `f` with this thread's file access confined to `roots` (unchanged when `None`).
+pub fn confined<R>(roots: Option<&Arc<Roots>>, f: impl FnOnce() -> R) -> R {
+    match roots {
+        Some(roots) => scoped(Some(roots.clone()), f),
+        None => f(),
+    }
+}
+
+/// Run `f` unconfined: only for the app's own files, never for a path a command was given.
+// Only plugins read from disk use it, and the browser has no disk.
+#[cfg_attr(target_arch = "wasm32", allow(dead_code))]
+pub(crate) fn app_owned<R>(f: impl FnOnce() -> R) -> R {
+    scoped(None, f)
+}
+
+fn scoped<R>(roots: Option<Arc<Roots>>, f: impl FnOnce() -> R) -> R {
+    /// Puts the outer scope's roots back, also when `f` panics.
+    struct Restore(Option<Arc<Roots>>);
+    impl Drop for Restore {
+        fn drop(&mut self) {
+            let outer = self.0.take();
+            ROOTS.with(|r| *r.borrow_mut() = outer);
+        }
+    }
+    let _restore = Restore(ROOTS.with(|r| std::mem::replace(&mut *r.borrow_mut(), roots)));
+    f()
+}
+
+/// The roots this thread's file access is confined to now, if any.
+pub fn current() -> Option<Arc<Roots>> {
+    ROOTS.with(|r| r.borrow().clone())
+}
+
+/// The path to use for `access` to `path`: resolved when confined, else as given.
+pub fn allow(path: impl AsRef<Path>, access: Access) -> Result<PathBuf> {
+    let path = path.as_ref();
+    match current() {
+        Some(roots) => roots.check(path, access).map_err(EngineError::Other),
+        None => Ok(path.to_path_buf()),
+    }
+}
+
+/// Whether `path` may be accessed so now.
+pub fn allowed(path: impl AsRef<Path>, access: Access) -> bool {
+    allow(path, access).is_ok()
+}
+
+fn io(path: &Path) -> impl Fn(std::io::Error) -> EngineError + '_ {
+    move |e| EngineError::Other(format!("{}: {e}", path.display()))
+}
+
+/// The bytes of file `path`.
+pub fn read(path: impl AsRef<Path>) -> Result<Vec<u8>> {
+    let path = path.as_ref();
+    std::fs::read(allow(path, Access::Read)?).map_err(io(path))
+}
+
+/// The bytes of file `path`, refused when it isn't a file or is larger than `max`.
+pub fn read_capped(path: impl AsRef<Path>, max: u64) -> Result<Vec<u8>> {
+    let path = path.as_ref();
+    let p = allow(path, Access::Read)?;
+    let meta = std::fs::metadata(&p).map_err(io(path))?;
+    if !meta.is_file() || meta.len() > max {
+        return Err(EngineError::Other(format!("{}: not a file of at most {max} bytes", path.display())));
+    }
+    std::fs::read(p).map_err(io(path))
+}
+
+/// File `path` opened for reading.
+pub fn open(path: impl AsRef<Path>) -> Result<std::fs::File> {
+    let path = path.as_ref();
+    std::fs::File::open(allow(path, Access::Read)?).map_err(io(path))
+}
+
+/// What the file system says about `path` (links followed).
+pub fn metadata(path: impl AsRef<Path>) -> Result<std::fs::Metadata> {
+    let path = path.as_ref();
+    std::fs::metadata(allow(path, Access::Read)?).map_err(io(path))
+}
+
+/// Whether `path` is a folder (false when it may not be read).
+pub fn is_dir(path: impl AsRef<Path>) -> bool {
+    metadata(path).is_ok_and(|m| m.is_dir())
+}
+
+/// Whether `path` exists (false when it may not be read).
+pub fn exists(path: impl AsRef<Path>) -> bool {
+    metadata(path).is_ok()
+}
+
+/// The paths of the entries of folder `path`.
+pub fn read_dir(path: impl AsRef<Path>) -> Result<Vec<PathBuf>> {
+    let path = path.as_ref();
+    let dir = allow(path, Access::Read)?;
+    Ok(std::fs::read_dir(&dir).map_err(io(path))?.flatten().map(|e| e.path()).collect())
+}
+
+/// Write `bytes` to `path` through a uniquely named staging file and one atomic rename (see
+/// [`figcraft_format::write_file_atomic`]).
+pub fn write(path: impl AsRef<Path>, bytes: &[u8]) -> Result<()> {
+    let path = path.as_ref();
+    write_atomic(&allow(path, Access::Write)?, bytes).map_err(io(path))
+}
+
+#[cfg(not(target_arch = "wasm32"))]
+fn write_atomic(path: &Path, bytes: &[u8]) -> std::io::Result<()> {
+    figcraft_format::write_file_atomic(path, bytes)
+}
+
+#[cfg(target_arch = "wasm32")]
+fn write_atomic(_: &Path, _: &[u8]) -> std::io::Result<()> {
+    Err(std::io::Error::new(std::io::ErrorKind::Unsupported, "no file system in the browser"))
+}
+
+/// Create folder `path` and the folders above it that are missing.
+pub fn create_dir_all(path: impl AsRef<Path>) -> Result<()> {
+    let path = path.as_ref();
+    std::fs::create_dir_all(allow(path, Access::Write)?).map_err(io(path))
+}
+
+#[cfg(test)]
+#[path = "file_access_tests.rs"]
+mod tests;

crates/engine/src/file_access_tests.rs

@@ -0,0 +1,388 @@
+//! Automation roots: how paths are resolved and compared, and that commands run confined can't
+//! reach past them.
+
+use std::path::{Path, PathBuf};
+use std::sync::Arc;
+
+use serde_json::json;
+
+use super::{Access, Roots, allow, confined, current};
+use crate::Session;
+
+/// A fresh folder for one test: `<tmp>/figcraft-roots-<name>-<pid>`, holding `root/`, `root2/`
+/// (a sibling whose name starts like the root's) and `outside/`.
+struct Fixture(PathBuf);
+
+impl Fixture {
+    fn new(name: &str) -> Self {
+        let d = std::env::temp_dir().join(format!("figcraft-roots-{name}-{}", std::process::id()));
+        let _ = std::fs::remove_dir_all(&d);
+        for sub in ["root/sub", "root2", "outside"] {
+            std::fs::create_dir_all(d.join(sub)).unwrap();
+        }
+        std::fs::write(d.join("root/in.txt"), b"in").unwrap();
+        std::fs::write(d.join("outside/secret.txt"), b"secret").unwrap();
+        Self(d)
+    }
+
+    fn p(&self, rel: &str) -> String {
+        self.0.join(rel).to_string_lossy().into_owned()
+    }
+
+    /// The root as both read and write root.
+    fn rw(&self) -> Roots {
+        Roots::new(&[], &[self.p("root")]).unwrap()
+    }
+}
+
+impl Drop for Fixture {
+    fn drop(&mut self) {
+        let _ = std::fs::remove_dir_all(&self.0);
+    }
+}
+
+#[cfg(unix)]
+fn symlink_dir(target: &Path, link: &Path) -> bool {
+    std::os::unix::fs::symlink(target, link).is_ok()
+}
+
+#[cfg(windows)]
+fn symlink_dir(target: &Path, link: &Path) -> bool {
+    std::os::windows::fs::symlink_dir(target, link).is_ok()
+}
+
+#[cfg(unix)]
+fn symlink_file(target: &Path, link: &Path) -> bool {
+    std::os::unix::fs::symlink(target, link).is_ok()
+}
+
+#[cfg(windows)]
+fn symlink_file(target: &Path, link: &Path) -> bool {
+    std::os::windows::fs::symlink_file(target, link).is_ok()
+}
+
+#[test]
+fn inside_is_allowed_and_resolved_outside_is_refused() {
+    let f = Fixture::new("inside");
+    let r = f.rw();
+    let got = r.check(Path::new(&f.p("root/in.txt")), Access::Read).unwrap();
+    assert_eq!(got, std::fs::canonicalize(f.p("root/in.txt")).unwrap(), "the I/O uses the resolved path");
+    assert!(r.check(Path::new(&f.p("root/new.png")), Access::Write).is_ok());
+    let e = r.check(Path::new(&f.p("outside/secret.txt")), Access::Read).unwrap_err();
+    assert!(e.starts_with("automation path rejected:") && e.contains("outside the folders that may be read"), "{e}");
+    assert!(r.check(Path::new(&f.p("outside/new.png")), Access::Write).is_err());
+    // The root itself is inside.
+    assert!(r.check(Path::new(&f.p("root")), Access::Read).is_ok());
+}
+
+#[test]
+fn a_sibling_whose_name_starts_like_the_root_is_outside() {
+    let f = Fixture::new("prefix");
+    let r = f.rw();
+    for p in ["root2/x.png", "root2", "root.png"] {
+        assert!(r.check(Path::new(&f.p(p)), Access::Write).is_err(), "{p}");
+        assert!(r.check(Path::new(&f.p(p)), Access::Read).is_err(), "{p}");
+    }
+}
+
+#[test]
+fn traversal_is_resolved_before_comparing() {
+    let f = Fixture::new("dots");
+    let r = f.rw();
+    assert!(r.check(Path::new(&f.p("root/sub/../../outside/secret.txt")), Access::Read).is_err());
+    assert!(r.check(Path::new(&f.p("root/sub/../../outside/new.txt")), Access::Write).is_err());
+    assert!(r.check(Path::new(&f.p("root/sub/../in.txt")), Access::Read).is_ok());
+    assert!(r.check(Path::new(&f.p("root/./sub/../new.txt")), Access::Write).is_ok());
+    // `..` below a folder that doesn't exist can't be resolved (on Windows it is taken lexically,
+    // as the system does, and stays inside).
+    let deep = f.p("root/missing/../../outside/x.txt");
+    assert!(r.check(Path::new(&deep), Access::Write).is_err(), "{deep}");
+}
+
+#[test]
+fn files_that_dont_exist_yet_resolve_through_their_nearest_folder() {
+    let f = Fixture::new("missing");
+    let r = f.rw();
+    let got = r.check(Path::new(&f.p("root/a/b/c.png")), Access::Write).unwrap();
+    assert_eq!(got, std::fs::canonicalize(f.p("root")).unwrap().join("a").join("b").join("c.png"));
+    assert!(r.check(Path::new(&f.p("outside/a/b/c.png")), Access::Write).is_err());
+}
+
+#[test]
+fn relative_paths_are_resolved_against_the_working_directory() {
+    // `cargo test` runs in the crate's folder, which holds Cargo.toml.
+    let cwd = std::env::current_dir().unwrap().to_string_lossy().into_owned();
+    let here = Roots::new(std::slice::from_ref(&cwd), &[]).unwrap();
+    assert_eq!(here.check(Path::new("Cargo.toml"), Access::Read).unwrap(), std::fs::canonicalize("Cargo.toml").unwrap());
+    assert!(here.check(Path::new("src/../Cargo.toml"), Access::Read).is_ok());
+    let f = Fixture::new("relative");
+    assert!(f.rw().check(Path::new("Cargo.toml"), Access::Read).is_err());
+    // Relative roots too.
+    assert_eq!(Roots::new(&[".".into()], &[]).unwrap(), here);
+}
+
+#[test]
+fn read_and_write_authority_are_separate() {
+    let f = Fixture::new("modes");
+    let read_only = Roots::new(&[f.p("root")], &[]).unwrap();
+    assert!(read_only.check(Path::new(&f.p("root/in.txt")), Access::Read).is_ok());
+    let e = read_only.check(Path::new(&f.p("root/out.png")), Access::Write).unwrap_err();
+    assert!(e.contains("no folder may be written"), "{e}");
+    // A write root may be read too; a read root elsewhere doesn't make it writable.
+    let both = Roots::new(&[f.p("outside")], &[f.p("root")]).unwrap();
+    assert!(both.check(Path::new(&f.p("root/in.txt")), Access::Read).is_ok());
+    assert!(both.check(Path::new(&f.p("outside/secret.txt")), Access::Read).is_ok());
+    assert!(both.check(Path::new(&f.p("outside/new.txt")), Access::Write).is_err());
+    // Several roots of each kind.
+    let many = Roots::new(&[f.p("root"), f.p("root2")], &[f.p("root2"), f.p("outside")]).unwrap();
+    assert!(many.check(Path::new(&f.p("outside/new.txt")), Access::Write).is_ok());
+    assert!(many.check(Path::new(&f.p("root/new.txt")), Access::Write).is_err());
+}
+
+#[test]
+fn roots_must_be_existing_folders() {
+    let f = Fixture::new("bad-roots");
+    assert!(Roots::new(&[f.p("nope")], &[]).unwrap_err().contains("--automation-read-root"));
+    assert!(Roots::new(&[], &[f.p("root/in.txt")]).unwrap_err().contains("not a folder"));
+    assert!(Roots::new(&[], &[String::new()]).is_err());
+    assert!(f.rw().check(Path::new(""), Access::Read).is_err());
+}
+
+#[test]
+fn links_that_lead_out_of_a_root_are_outside() {
+    let f = Fixture::new("links");
+    let r = f.rw();
+    if !symlink_dir(&f.0.join("outside"), &f.0.join("root/escape")) || !symlink_file(&f.0.join("outside/secret.txt"), &f.0.join("root/secret.txt")) {
+        eprintln!("skipped: this system doesn't let tests make symbolic links");
+        return;
+    }
+    assert!(r.check(Path::new(&f.p("root/escape/secret.txt")), Access::Read).is_err());
+    assert!(r.check(Path::new(&f.p("root/escape/new.txt")), Access::Write).is_err());
+    assert!(r.check(Path::new(&f.p("root/secret.txt")), Access::Read).is_err());
+    assert!(r.check(Path::new(&f.p("root/secret.txt")), Access::Write).is_err());
+    // A link that leads nowhere: writing through it would create its target.
+    assert!(symlink_file(&f.0.join("outside/not-yet.txt"), &f.0.join("root/dangling.txt")));
+    let e = r.check(Path::new(&f.p("root/dangling.txt")), Access::Write).unwrap_err();
+    assert!(e.contains("leads nowhere"), "{e}");
+    // A link inside the root to the root is fine.
+    assert!(symlink_dir(&f.0.join("root/sub"), &f.0.join("root/alias")));
+    assert!(r.check(Path::new(&f.p("root/alias/x.png")), Access::Write).is_ok());
+}
+
+#[cfg(windows)]
+#[test]
+fn windows_case_devices_and_streams() {
+    let f = Fixture::new("windows");
+    let r = f.rw();
+    // Case is taken from the disk: another spelling of the root is the root.
+    let upper = f.0.join("ROOT").join("IN.TXT");
+    assert!(r.check(&upper, Access::Read).is_ok());
+    for name in ["CON", "nul.txt", "Com1.png", "LPT9", "a.txt:stream", "conout$"] {
+        assert!(r.check(&f.0.join("root").join(name), Access::Write).is_err(), "{name}");
+    }
+    assert!(r.check(&f.0.join("root").join("console.png"), Access::Write).is_ok());
+    // The `\\?\` form of a path inside is inside; of a path outside, outside.
+    let verbatim = std::fs::canonicalize(f.p("root")).unwrap().join("v.png");
+    assert!(verbatim.to_string_lossy().starts_with(r"\\?\"));
+    assert!(r.check(&verbatim, Access::Write).is_ok());
+    assert!(r.check(&std::fs::canonicalize(f.p("outside")).unwrap().join("v.png"), Access::Write).is_err());
+    // Messages don't show the prefix.
+    let e = r.check(Path::new(&f.p("outside/x.png")), Access::Write).unwrap_err();
+    assert!(!e.contains(r"\\?\"), "{e}");
+}
+
+#[test]
+fn a_scope_confines_the_thread_and_ends_with_it() {
+    let f = Fixture::new("scope");
+    let roots = Arc::new(f.rw());
+    assert!(current().is_none());
+    confined(Some(&roots), || {
+        assert!(allow(f.p("outside/secret.txt"), Access::Read).is_err());
+        assert!(super::read(f.p("outside/secret.txt")).is_err());
+        assert_eq!(super::read(f.p("root/in.txt")).unwrap(), b"in");
+        // Not confined: the app's own files.
+        assert_eq!(super::app_owned(|| super::read(f.p("outside/secret.txt")).unwrap()), b"secret");
+        assert!(current().is_some(), "back in the scope after app_owned");
+        // Another thread isn't confined by this one's scope.
+        let p = f.p("outside/secret.txt");
+        assert!(std::thread::spawn(move || current().is_none() && allow(p, Access::Read).is_ok()).join().unwrap());
+    });
+    assert!(current().is_none());
+    assert!(allow(f.p("outside/secret.txt"), Access::Read).is_ok());
+    // A panic inside the scope still ends it.
+    let r = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| confined(Some(&roots), || panic!("boom"))));
+    assert!(r.is_err());
+    assert!(current().is_none());
+    // `None` changes nothing.
+    assert!(confined(None, || current().is_none()));
+}
+
+#[test]
+fn commands_run_confined_read_and_write_only_inside() {
+    let f = Fixture::new("commands");
+    std::fs::create_dir_all(f.0.join("outside/readable")).unwrap();
+    let roots = Arc::new(Roots::new(&[f.p("outside/readable")], &[f.p("root")]).unwrap());
+    // Unconfined, the outside is writable: the bait files a confined command must not reach.
+    let bait = f.p("outside/bait.figcraft");
+    let mut s = Session::new();
+    s.execute("frame.create", &json!({"x": 0, "y": 0, "width": 20, "height": 10})).unwrap();
+    s.execute("file.saveAs", &json!({"path": bait})).unwrap();
+    std::fs::copy(&bait, f.0.join("outside/readable/ok.figcraft")).unwrap();
+    let mut s = Session::new();
+    s.execute("frame.create", &json!({"x": 0, "y": 0, "width": 20, "height": 10})).unwrap();
+    s.prefs.recent_files = vec![bait.clone(), f.p("root/in.txt")];
+    confined(Some(&roots), || {
+        let e = s.execute("file.export", &json!({"format": "png", "path": f.p("outside/x.png")})).unwrap_err().to_string();
+        assert!(e.contains("automation path rejected"), "{e}");
+        assert!(s.execute("file.export", &json!({"format": "png", "path": f.p("root/x.png")})).is_ok());
+        assert!(s.execute("file.exportLayers", &json!({"dir": f.p("outside/layers")})).is_err());
+        assert!(s.execute("file.open", &json!({"path": bait})).is_err());
+        assert!(s.execute("file.import", &json!({"path": bait})).is_err());
+        assert!(s.execute("file.placeImage", &json!({"path": f.p("outside/secret.txt")})).is_err());
+        assert!(s.execute("file.open", &json!({"path": f.p("outside/readable/ok.figcraft")})).is_ok(), "read roots may be read");
+        assert!(s.execute("file.save", &json!({})).is_err(), "but not written");
+        assert!(s.execute("file.saveAs", &json!({"path": f.p("root/ok.figcraft")})).is_ok());
+        // Recent files outside the roots aren't listed.
+        let recent = s.execute("file.openRecent", &json!({})).unwrap().to_string();
+        assert!(!recent.contains("bait") && recent.contains("in.txt"), "{recent}");
+        assert!(s.execute("file.openRecent", &json!({"path": bait})).is_err());
+    });
+    assert!(f.0.join("root/x.png").is_file() && !f.0.join("outside/x.png").exists() && !f.0.join("outside/layers").exists());
+}
+
+/// Every command, given paths outside the roots in its usual path parameters, writes nothing
+/// there and opens nothing from there: they all reach files through `file_access`.
+#[test]
+fn no_command_reaches_outside_the_roots() {
+    let f = Fixture::new("sweep");
+    let roots = Arc::new(f.rw());
+    let outside = f.0.join("outside");
+    // Bait the sweep could pick up: a document, an SVG, a PNG and variables JSON, each holding a
+    // name that must never show up in a document or a result.
+    let mut s = Session::new();
+    s.execute("frame.create", &json!({"x": 0, "y": 0, "width": 20, "height": 10, "name": "BAIT-LAYER"})).unwrap();
+    s.execute("file.saveAs", &json!({"path": f.p("outside/bait.figcraft")})).unwrap();
+    s.execute("file.export", &json!({"format": "png", "path": f.p("outside/bait.png")})).unwrap();
+    std::fs::write(
+        outside.join("bait.svg"),
+        r#"<svg xmlns="http://www.w3.org/2000/svg" width="9" height="9"><rect id="BAIT-LAYER" width="9" height="9"/></svg>"#,
+    )
+    .unwrap();
+    let before: Vec<_> = std::fs::read_dir(&outside).unwrap().flatten().map(|e| e.file_name()).collect();
+    // The bait is what an unconfined command finds.
+    for (cmd, bait) in [("file.open", "bait.figcraft"), ("file.import", "bait.svg")] {
+        let mut s = Session::new();
+        s.execute(cmd, &json!({"path": f.p(&format!("outside/{bait}"))})).unwrap();
+        assert!(crate::inspect::document(&s, 64, true).to_string().contains("BAIT-LAYER"), "{cmd} {bait}");
+    }
+    let mut s = Session::new();
+    s.execute("file.placeImage", &json!({"path": f.p("outside/bait.png")})).unwrap();
+    assert!(!s.doc().unwrap().images.is_empty());
+    for bait in ["bait.figcraft", "bait.svg", "bait.png", "new.figcraft", "new.png"] {
+        let path = f.p(&format!("outside/{bait}"));
+        let params = json!({"path": path, "dir": f.p("outside"), "file": path, "variables": path, "folder": f.p("outside"), "confirm": true});
+        for c in crate::all_commands() {
+            let mut s = Session::new();
+            let r = confined(Some(&roots), || s.execute(c.id, &params));
+            let shown = format!("{r:?}");
+            assert!(!shown.contains("BAIT-LAYER"), "{} read {bait}: {shown}", c.id);
+            let docs = crate::inspect::document(&s, 64, true).to_string();
+            assert!(!docs.contains("BAIT-LAYER"), "{} opened {bait}", c.id);
+            assert!(s.docs.iter().all(|ds| ds.doc.images.is_empty()), "{} placed {bait}", c.id);
+            let now: Vec<_> = std::fs::read_dir(&outside).unwrap().flatten().map(|e| e.file_name()).collect();
+            assert_eq!(now, before, "{} wrote outside the roots with {bait}", c.id);
+        }
+    }
+}
+
+#[test]
+fn recent_files_outside_the_roots_are_never_opened_removed_or_named() {
+    let f = Fixture::new("recents");
+    let roots = Arc::new(f.rw());
+    let (bait, gone, ok) = (f.p("outside/bait.figcraft"), f.p("outside/gone.figcraft"), f.p("root/ok.figcraft"));
+    let mut s = Session::new();
+    s.execute("frame.create", &json!({"x": 0, "y": 0, "width": 20, "height": 10})).unwrap();
+    s.execute("file.saveAs", &json!({"path": bait})).unwrap();
+    s.execute("file.saveAs", &json!({"path": ok})).unwrap();
+    let mut s = Session::new();
+    let recents = vec![bait.clone(), gone.clone(), ok.clone()];
+    s.prefs.recent_files = recents.clone();
+    let quiet = |r: &crate::Result<serde_json::Value>| {
+        let shown = format!("{r:?}");
+        assert!(!shown.contains("bait") && !shown.contains("gone"), "an outside recent file was named: {shown}");
+    };
+    confined(Some(&roots), || {
+        let listing = s.execute("file.openRecent", &json!({}));
+        quiet(&listing);
+        assert_eq!(listing.unwrap()["files"].as_array().unwrap().len(), 1);
+        // `index` counts the files listed: 0 is the first one inside the roots.
+        let opened = s.execute("file.openRecent", &json!({"index": 0}));
+        quiet(&opened);
+        assert!(opened.is_ok(), "{opened:?}");
+        assert_eq!(s.ds().unwrap().path.as_deref(), Some(ok.as_str()));
+        for i in [1, 2] {
+            let r = s.execute("file.openRecent", &json!({"index": i}));
+            quiet(&r);
+            assert!(r.is_err());
+        }
+        // A path outside is refused like any outside path, and never dropped from the list.
+        let e = s.execute("file.openRecent", &json!({"path": gone})).unwrap_err().to_string();
+        assert!(e.contains("is outside the folders that may be read") && !e.contains("no longer exists"), "{e}");
+        quiet(&s.execute("file.openRecent", &json!({"remove": bait})));
+        assert!(s.prefs.recent_files.contains(&bait) && s.prefs.recent_files.contains(&gone));
+        // Clear clears what is listed.
+        quiet(&s.execute("file.openRecent", &json!({"clear": true})));
+    });
+    assert_eq!(s.prefs.recent_files, vec![bait, gone]);
+    // Unconfined, a recent file that is gone is still dropped.
+    s.execute("file.openRecent", &json!({"index": 1})).unwrap_err();
+    assert_eq!(s.prefs.recent_files.len(), 1);
+}
+
+#[test]
+fn outside_paths_are_refused_alike_whatever_exists_there() {
+    let f = Fixture::new("oracle");
+    let r = f.rw();
+    let refusal = |p: &str| r.check(Path::new(p), Access::Write).unwrap_err();
+    let standard = |p: &str| format!("automation path rejected: {} is outside the folders that may be written:", Path::new(p).display());
+    let mut outside = vec![f.p("outside/secret.txt"), f.p("outside/none.txt"), f.p("outside/missing/../x.txt"), f.p("nowhere/deeper/x.txt")];
+    if symlink_file(&f.0.join("outside/not-yet.txt"), &f.0.join("outside/dangling.txt")) {
+        outside.push(f.p("outside/dangling.txt"));
+        // Reached through a link in the root, it is outside all the same.
+        if symlink_dir(&f.0.join("outside"), &f.0.join("root/escape")) {
+            outside.push(f.p("root/escape/dangling.txt"));
+        }
+    }
+    for p in &outside {
+        let e = refusal(p);
+        assert!(e.starts_with(&standard(p)), "{p}: {e}");
+    }
+    // Inside a root the reason is given.
+    if symlink_file(&f.0.join("outside/not-yet.txt"), &f.0.join("root/dangling.txt")) {
+        assert!(refusal(&f.p("root/dangling.txt")).contains("leads nowhere"));
+    }
+}
+
+#[test]
+fn a_root_given_through_a_link_tells_why_paths_in_it_are_refused() {
+    let f = Fixture::new("linked-root");
+    if !symlink_dir(&f.0.join("root"), &f.0.join("via")) || !symlink_file(&f.0.join("outside/not-yet.txt"), &f.0.join("root/dangling.txt")) {
+        eprintln!("skipped: this system doesn't let tests make symbolic links");
+        return;
+    }
+    // Like `/tmp/work` on macOS, where `/tmp` leads to `/private/tmp`.
+    let r = Roots::new(&[], &[f.p("via")]).unwrap();
+    let e = r.check(Path::new(&f.p("via/dangling.txt")), Access::Write).unwrap_err();
+    assert!(e.contains("leads nowhere"), "{e}");
+}
+
+#[test]
+fn only_resolved_paths_count_as_the_apps_own_folder() {
+    let f = Fixture::new("own");
+    let install = f.0.join("root");
+    assert!(super::within_app_folder(&install.join("in.txt"), &install));
+    assert!(!super::within_app_folder(&install.join("..").join("outside").join("secret.txt"), &install), "`..` leaves it");
+    assert!(!super::within_app_folder(&f.0.join("root2"), &install), "a folder named like it is another");
+    assert!(!super::within_app_folder(&install.join("missing.wasm"), &install));
+    assert!(!super::within_app_folder(&install.join("in.txt"), &f.0.join("no-such-folder")));
+}

crates/engine/src/finite_geometry_tests.rs

@@ -0,0 +1,40 @@
+//! Commands never leave a layer with a non-finite position or size: such a file saves but can't be
+//! reopened (JSON writes NaN and infinity as null).
+
+use serde_json::json;
+
+use crate::Session;
+
+fn rect(s: &mut Session) -> crate::NodeId {
+    let r = s.execute("node.create", &json!({"type": "rectangle", "x": 0, "y": 10, "width": 100, "height": 50})).unwrap();
+    crate::params::id_of(&r["id"]).unwrap()
+}
+
+fn assert_roundtrips(s: &Session) {
+    let bytes = figcraft_format::save_bytes(s.doc().unwrap(), None).unwrap();
+    assert!(figcraft_format::load_bytes(&bytes).is_ok(), "the saved file reopens");
+}
+
+#[test]
+fn huge_moves_are_refused_and_the_file_still_reopens() {
+    let mut s = Session::new();
+    let r = rect(&mut s);
+    s.execute("transform.move", &json!({"ids": [r], "dx": 1e308, "dy": 0})).ok();
+    let second = s.execute("transform.move", &json!({"ids": [r], "dx": 1e308, "dy": 1e308}));
+    assert!(second.is_err(), "a move past the f64 range is refused");
+    let n = s.doc().unwrap().node(r).unwrap();
+    assert!(n.transform.as_coeffs().iter().all(|c| c.is_finite()), "{:?}", n.transform);
+    assert_roundtrips(&s);
+}
+
+#[test]
+fn huge_scale_is_refused_and_the_file_still_reopens() {
+    let mut s = Session::new();
+    let r = rect(&mut s);
+    s.execute("transform.scale", &json!({"ids": [r], "factor": 1e300})).ok();
+    let second = s.execute("transform.scale", &json!({"ids": [r], "factor": 1e300}));
+    assert!(second.is_err(), "a size past the f64 range is refused");
+    let n = s.doc().unwrap().node(r).unwrap();
+    assert!(n.width.is_finite() && n.height.is_finite(), "{} x {}", n.width, n.height);
+    assert_roundtrips(&s);
+}

crates/engine/src/fonts.rs

@@ -0,0 +1,100 @@
+//! Fonts a document names that this machine doesn't have (#752): text layers, their styled
+//! ranges, text styles and the string variables bound to a font family. Text in such a family
+//! is drawn in a fallback font, so the user is told which ones are missing.
+
+use std::collections::BTreeMap;
+
+use figcraft_doc::{Document, NodeKind, StyleKind, VariableValue, Variables};
+use serde_json::{Value, json};
+
+use crate::cmd::CommandSpec;
+use crate::{Result, Session, spec};
+
+/// A family the document names that no installed or built-in font provides.
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct Missing {
+    /// As the document spells it.
+    pub family: String,
+    /// Text layers that use it (0: only a text style or a variable names it).
+    pub layers: usize,
+}
+
+/// The families `doc` names that the font database doesn't have, by name. On the desktop the
+/// installed fonts are indexed in the background: ask once that's done
+/// (`figcraft_text::installed_fonts_known`), or every installed family counts as missing.
+pub fn missing(doc: &Document) -> Vec<Missing> {
+    // Lower-case family → (spelling, layers).
+    let mut used: BTreeMap<String, (String, usize)> = BTreeMap::new();
+    let mut add = |family: &str, layer: bool| {
+        let family = family.trim();
+        if family.is_empty() {
+            return;
+        }
+        let e = used.entry(family.to_lowercase()).or_insert_with(|| (family.to_string(), 0));
+        e.1 += usize::from(layer);
+    };
+    for n in doc.nodes() {
+        if let NodeKind::Text(t) = &n.kind {
+            let mut families: Vec<&str> = t.spans().into_iter().map(|(_, _, st)| st.font_family.as_str()).collect();
+            families.push(&t.style.font_family);
+            families.sort_by_key(|f| f.trim().to_lowercase());
+            families.dedup_by_key(|f| f.trim().to_lowercase());
+            for f in families {
+                add(f, true);
+            }
+        }
+        if let Some(var) = n.bound.get("fontFamily") {
+            for f in string_values(&doc.variables, var) {
+                add(&f, false);
+            }
+        }
+    }
+    for st in &doc.styles {
+        if let StyleKind::Text { style } = &st.kind {
+            add(&style.font_family, false);
+        }
+        if let Some(var) = st.bound.get("fontFamily") {
+            for f in string_values(&doc.variables, var) {
+                add(&f, false);
+            }
+        }
+    }
+    used.into_values().filter(|(family, _)| !figcraft_text::has_family(family)).map(|(family, layers)| Missing { family, layers }).collect()
+}
+
+/// Every string value of variable `id` in any mode, following aliases (at most 32 deep).
+fn string_values(vars: &Variables, id: &str) -> Vec<String> {
+    let mut out = Vec::new();
+    let mut todo = vec![(id.to_string(), 0)];
+    while let Some((id, depth)) = todo.pop() {
+        let Some(var) = vars.get(&id) else { continue };
+        for v in var.values.values() {
+            match v {
+                VariableValue::String(s) => out.push(s.clone()),
+                VariableValue::Alias(a) if depth < 32 => todo.push((a.clone(), depth + 1)),
+                _ => {}
+            }
+        }
+    }
+    out
+}
+
+fn missing_fonts(s: &mut Session, _: &Value) -> Result<Value> {
+    let families: Vec<Value> = missing(s.doc()?).into_iter().map(|m| json!({"family": m.family, "layers": m.layers})).collect();
+    s.request_ui("dialog.missingFonts", json!({}));
+    Ok(json!({"families": families}))
+}
+
+pub fn specs() -> Vec<CommandSpec> {
+    vec![spec!(
+        "text.missingFonts",
+        "Missing fonts",
+        "{}  fonts the open document names that aren't installed (text layers, styled ranges, text styles, font family variables); the app shows them → {families: [{family, layers}]}",
+        false,
+        missing_fonts
+    )]
+}
+
+#[cfg(test)]
+#[path = "fonts_tests.rs"]
+mod tests;

crates/engine/src/fonts_tests.rs

@@ -0,0 +1,126 @@
+use serde_json::json;
+
+use super::*;
+use crate::params::id_of;
+use figcraft_doc::{Style, StyleRun, TextStyle};
+
+fn text(s: &mut Session, family: &str) -> figcraft_doc::NodeId {
+    let id = id_of(&s.execute("text.create", &json!({"text": "Hamburgefonstiv", "x": 0, "y": 0})).unwrap()["id"]).unwrap();
+    if let NodeKind::Text(t) = &mut s.doc_mut().unwrap().get_mut(id).unwrap().kind {
+        t.style.font_family = family.into();
+    }
+    id
+}
+
+fn families(s: &mut Session) -> Vec<(String, u64)> {
+    let r = s.execute("text.missingFonts", &json!({})).unwrap();
+    r["families"].as_array().unwrap().iter().map(|f| (f["family"].as_str().unwrap().to_string(), f["layers"].as_u64().unwrap())).collect()
+}
+
+/// An installed family (built in, or found by the system scan), if this machine has any.
+fn installed() -> Option<String> {
+    figcraft_text::scan_system_fonts();
+    figcraft_text::family_names().into_iter().next()
+}
+
+#[test]
+fn lists_families_of_layers_ranges_styles_and_variables_once_each() {
+    let mut s = Session::new();
+    text(&mut s, "FigCraft Missing A");
+    let b = text(&mut s, "figcraft missing a");
+    if let NodeKind::Text(t) = &mut s.doc_mut().unwrap().get_mut(b).unwrap().kind {
+        let style = TextStyle { font_family: "FigCraft Missing B".into(), ..t.style.clone() };
+        t.runs.push(StyleRun { start: 0, end: 3, style });
+    }
+    let doc = s.doc_mut().unwrap();
+    doc.styles.push(Style {
+        id: "S:1".into(),
+        name: "Heading".into(),
+        description: String::new(),
+        kind: StyleKind::Text { style: TextStyle { font_family: "FigCraft Missing C".into(), ..TextStyle::default() } },
+        bound: Default::default(),
+    });
+    s.execute("variable.createCollection", &json!({"name": "Type", "modes": ["Light", "Dark"]})).unwrap();
+    s.execute("variable.create", &json!({"collection": "Type", "name": "Family", "type": "string", "value": "FigCraft Missing D"})).unwrap();
+    s.execute("variable.set", &json!({"variable": "Family", "mode": "Dark", "value": "FigCraft Missing H"})).unwrap();
+    let var = s.doc().unwrap().variables.get("Family").unwrap().id.clone();
+    s.doc_mut().unwrap().get_mut(b).unwrap().bound.insert("fontFamily".into(), var);
+
+    assert_eq!(
+        families(&mut s),
+        vec![
+            ("FigCraft Missing A".to_string(), 2),
+            ("FigCraft Missing B".to_string(), 1),
+            ("FigCraft Missing C".to_string(), 0),
+            ("FigCraft Missing D".to_string(), 0),
+            ("FigCraft Missing H".to_string(), 0),
+        ]
+    );
+    assert!(s.ui_requests.iter().any(|r| r.kind == "dialog.missingFonts"));
+}
+
+#[test]
+fn installed_families_are_not_listed() {
+    let Some(family) = installed() else {
+        eprintln!("skipped: no fonts on this machine");
+        return;
+    };
+    let mut s = Session::new();
+    text(&mut s, &family);
+    text(&mut s, &family.to_uppercase());
+    text(&mut s, "FigCraft Missing E");
+    assert_eq!(families(&mut s), vec![("FigCraft Missing E".to_string(), 1)]);
+}
+
+#[test]
+fn a_family_found_only_by_the_system_scan_is_not_missing() {
+    figcraft_text::scan_system_fonts();
+    let embedded: Vec<String> = figcraft_text::CRAFT_FONTS.iter().map(|f| f.family.to_lowercase()).collect();
+    let Some(family) = figcraft_text::family_names().into_iter().find(|f| !embedded.contains(&f.to_lowercase())) else {
+        eprintln!("skipped: no system fonts on this machine");
+        return;
+    };
+    let mut s = Session::new();
+    text(&mut s, &family);
+    assert!(families(&mut s).is_empty(), "{family} is installed");
+}
+
+#[test]
+fn blank_families_and_aliases_are_handled() {
+    let mut s = Session::new();
+    text(&mut s, "  ");
+    s.execute("variable.createCollection", &json!({"name": "Type"})).unwrap();
+    s.execute("variable.create", &json!({"collection": "Type", "name": "Base", "type": "string", "value": "FigCraft Missing F"})).unwrap();
+    let base = s.doc().unwrap().variables.get("Base").unwrap().id.clone();
+    let t = text(&mut s, "FigCraft Missing G");
+    let doc = s.doc_mut().unwrap();
+    // A variable that only aliases another, and one aliasing itself.
+    let mut alias = doc.variables.get(&base).unwrap().clone();
+    alias.id = "V:alias".into();
+    alias.name = "Alias".into();
+    for v in alias.values.values_mut() {
+        *v = VariableValue::Alias(base.clone());
+    }
+    let mut cycle = alias.clone();
+    cycle.id = "V:cycle".into();
+    cycle.name = "Cycle".into();
+    for v in cycle.values.values_mut() {
+        *v = VariableValue::Alias("V:cycle".into());
+    }
+    doc.variables.variables.push(alias);
+    doc.variables.variables.push(cycle);
+    doc.get_mut(t).unwrap().bound.insert("fontFamily".into(), "V:alias".into());
+    let other = text(&mut s, "FigCraft Missing G");
+    s.doc_mut().unwrap().get_mut(other).unwrap().bound.insert("fontFamily".into(), "V:cycle".into());
+    // The bound layer takes the value its alias resolves to (bindings are applied after the next
+    // command); the cycle resolves to nothing.
+    let NodeKind::Text(bound) = &s.doc().unwrap().node(t).unwrap().kind else { panic!() };
+    assert_eq!(bound.style.font_family, "FigCraft Missing F");
+    assert_eq!(families(&mut s), vec![("FigCraft Missing F".to_string(), 1), ("FigCraft Missing G".to_string(), 1)]);
+}
+
+#[test]
+fn needs_an_open_document() {
+    let mut s = Session::empty();
+    assert!(s.execute("text.missingFonts", &json!({})).is_err());
+}

crates/engine/src/frame_label_tests.rs

@@ -1,6 +1,7 @@
 //! Frame name labels as pointer targets: a press on a label (its area as the canvas drew it,
 //! turned with a rotated frame) selects the frame and drags it in one undo step, hovering it
-//! highlights the frame, and labels of locked, hidden, deleted or other pages' frames do nothing.
+//! highlights the frame, a double-click asks the UI to rename it there, and labels of locked,
+//! hidden, deleted or other pages' frames do nothing.
 
 use figcraft_doc::NodeId;
 use figcraft_geom::Point;
@@ -90,3 +91,24 @@ fn labels_of_frames_that_cant_be_picked_do_nothing() {
     let flat = [Point::new(1.0, 1.0); 4];
     assert_eq!(label_at(s.doc().unwrap(), page, &[(f, nan), (f, flat)], Point::new(1.0, 1.0)), None);
 }
+
+#[test]
+fn double_clicking_a_label_asks_to_rename_its_frame() {
+    let (mut s, f, q) = setup();
+    let c = center(&q);
+    let before = s.doc().unwrap().world_bounds(f).unwrap();
+    let undo = s.ds().unwrap().history.undo.len();
+    for kind in [PointerKind::Down, PointerKind::Up, PointerKind::Down, PointerKind::DoubleClick] {
+        s.pointer(&ev(kind, c)).unwrap();
+    }
+    assert_eq!(s.selection(), vec![f]);
+    let asked = s.ui_requests.iter().find(|r| r.kind == "canvas.renameLabel").map(|r| id_of(&r.data["id"]));
+    assert_eq!(asked, Some(Some(f)), "the UI renames the frame at its label");
+    assert_eq!(s.doc().unwrap().world_bounds(f), Some(before), "not moved");
+    assert_eq!(s.ds().unwrap().history.undo.len(), undo, "nothing to undo yet");
+    // Other tools ignore the label.
+    s.ui_requests.clear();
+    s.set_tool(crate::tools::ToolId::Hand);
+    s.pointer(&ev(PointerKind::DoubleClick, c)).unwrap();
+    assert!(s.ui_requests.iter().all(|r| r.kind != "canvas.renameLabel"));
+}

crates/engine/src/id_params_behaviour_tests.rs

@@ -0,0 +1,161 @@
+//! Layer ids in params: naming something that isn't a layer is a mistake, and says so, rather than
+//! quietly meaning "none".
+//!
+//! `node.create`'s `parent` was `id(p, "parent").unwrap_or(page)`, so any value that isn't an id —
+//! a `{"$step": n}` nothing had resolved, a name, a negative number — became "no parent" and the
+//! layer landed on the page while the call reported success. The same shape sat on `image.place`
+//! and `instance.create`'s parents, on `index`, and on the `ids` of every command that targets
+//! layers (an entry that wasn't an id was dropped and the rest ran).
+
+use crate::params::id_of;
+use crate::{EngineError, Session};
+use figcraft_doc::*;
+use serde_json::{Value, json};
+
+/// The page's children, by name (bottom first).
+fn top(s: &Session) -> Vec<String> {
+    let doc = s.doc().unwrap();
+    let page = s.page().unwrap();
+    doc.node(page).unwrap().children.iter().filter_map(|c| doc.node(*c).map(|n| n.name.clone())).collect()
+}
+
+/// The message of a failure, or `None` when the call went through.
+fn failed(r: std::result::Result<Value, EngineError>) -> Option<String> {
+    match r {
+        Ok(_) => None,
+        Err(e) => Some(e.to_string()),
+    }
+}
+
+fn rect(parent: Value) -> Value {
+    json!({"type": "rectangle", "name": "child", "parent": parent, "x": 0, "y": 0, "width": 10, "height": 10})
+}
+
+fn card(s: &mut Session) -> NodeId {
+    let v = s.execute("node.create", &json!({"type": "frame", "name": "Card", "x": 0, "y": 0, "width": 100, "height": 100})).unwrap();
+    id_of(&v["id"]).unwrap()
+}
+
+#[test]
+fn a_parent_that_is_not_an_id_is_refused_rather_than_becoming_the_page() {
+    let mut s = Session::new();
+    let card = card(&mut s);
+    for parent in [json!({"$step": 0}), json!("Card"), json!(-1), json!(true)] {
+        let msg = failed(s.execute("node.create", &rect(parent.clone()))).unwrap_or_else(|| panic!("{parent} must be refused"));
+        assert!(msg.contains("`parent` must be a node id"), "{parent}: {msg}");
+    }
+    assert_eq!(top(&s), ["Card"], "nothing landed on the page");
+    let doc = s.doc().unwrap();
+    assert!(doc.node(card).unwrap().children.is_empty(), "nor inside the frame");
+}
+
+#[test]
+fn leaving_the_parent_out_or_null_still_means_the_page() {
+    let mut s = Session::new();
+    let card = card(&mut s);
+    for parent in [None, Some(json!(null))] {
+        let mut p = rect(json!(0));
+        match parent {
+            None => _ = p.as_object_mut().unwrap().remove("parent"),
+            Some(v) => p["parent"] = v,
+        }
+        s.execute("node.create", &p).unwrap();
+    }
+    assert_eq!(top(&s), ["Card", "child", "child"]);
+    let doc = s.doc().unwrap();
+    assert!(doc.node(card).unwrap().children.is_empty());
+}
+
+#[test]
+fn a_parent_id_that_names_nothing_is_still_reported() {
+    let mut s = Session::new();
+    card(&mut s);
+    let msg = failed(s.execute("node.create", &rect(json!(99999)))).unwrap_or_else(|| panic!("a missing layer must fail"));
+    assert!(msg.contains("no such node 99999"), "{msg}");
+}
+
+#[test]
+fn an_index_that_is_not_a_whole_non_negative_number_is_refused() {
+    let mut s = Session::new();
+    let card = card(&mut s);
+    // (A boolean is a number to `f64_of` — `true` reads as 1 — as for `x`, `width` and every
+    // other number, so it is deliberately not in this list.)
+    for index in [json!("last"), json!(1.5), json!(-1), json!(-0.5), json!(1e12)] {
+        let mut p = rect(json!(card));
+        p["index"] = index.clone();
+        let msg = failed(s.execute("node.create", &p)).unwrap_or_else(|| panic!("index {index} must be refused"));
+        assert!(msg.contains("`index`"), "{index}: {msg}");
+    }
+    let doc = s.doc().unwrap();
+    assert!(doc.node(card).unwrap().children.is_empty(), "nothing was inserted");
+}
+
+#[test]
+fn a_whole_index_still_inserts_where_it_says() {
+    let mut s = Session::new();
+    let card = card(&mut s);
+    for name in ["a", "b"] {
+        s.execute("node.create", &json!({"type": "rectangle", "name": name, "parent": card, "x": 0, "y": 0, "width": 10, "height": 10})).unwrap();
+    }
+    s.execute("node.create", &json!({"type": "rectangle", "name": "mid", "parent": card, "index": 1, "x": 0, "y": 0, "width": 10, "height": 10}))
+        .unwrap();
+    let doc = s.doc().unwrap();
+    let names: Vec<&str> = doc.node(card).unwrap().children.iter().filter_map(|c| doc.node(*c).map(|n| n.name.as_str())).collect();
+    assert_eq!(names, ["a", "mid", "b"]);
+}
+
+#[test]
+fn ids_entries_that_are_not_ids_are_refused_instead_of_being_dropped() {
+    let mut s = Session::new();
+    let card = card(&mut s);
+    // The junk used to be dropped and the rest applied, so `["nope", card]` renamed the frame.
+    for ids in [json!(["nope"]), json!(["nope", card]), json!([{"$step": 0}, card]), json!([null])] {
+        let msg =
+            failed(s.execute("node.set", &json!({"ids": ids, "props": {"name": "renamed"}}))).unwrap_or_else(|| panic!("{ids} must be refused"));
+        assert!(msg.contains("`ids`"), "{ids}: {msg}");
+    }
+    let doc = s.doc().unwrap();
+    assert_eq!(doc.node(card).unwrap().name, "Card", "nothing was renamed");
+}
+
+#[test]
+fn an_ids_that_is_not_an_array_is_refused_but_null_means_the_selection() {
+    let mut s = Session::new();
+    let card = card(&mut s);
+    let msg =
+        failed(s.execute("node.set", &json!({"ids": "nope", "props": {"name": "renamed"}}))).unwrap_or_else(|| panic!("a non-array ids must fail"));
+    assert!(msg.contains("`ids` must be an array"), "{msg}");
+    // An explicit null says the same as leaving it out: the selection.
+    s.execute("select.set", &json!({"ids": [card]})).unwrap();
+    s.execute("node.set", &json!({"ids": null, "props": {"name": "Selected"}})).unwrap();
+    assert_eq!(s.doc().unwrap().node(card).unwrap().name, "Selected");
+}
+
+#[test]
+fn a_single_id_that_is_not_an_id_is_refused() {
+    let mut s = Session::new();
+    card(&mut s);
+    let msg =
+        failed(s.execute("node.set", &json!({"id": {"$step": 0}, "props": {"name": "renamed"}}))).unwrap_or_else(|| panic!("a bad id must fail"));
+    assert!(msg.contains("`id` must be a node id"), "{msg}");
+}
+
+#[test]
+fn an_image_and_an_instance_parent_are_checked_the_same_way() {
+    let mut s = Session::new();
+    card(&mut s);
+    let img = failed(s.execute("image.place", &json!({"data": "aGk=", "parent": {"$step": 0}})));
+    assert!(img.unwrap_or_default().contains("`parent` must be a node id"), "image.place");
+    let inst = failed(s.execute("instance.create", &json!({"component": 99999, "parent": {"$step": 0}})));
+    assert!(inst.is_some(), "instance.create refuses both a bad component and a bad parent");
+}
+
+#[test]
+fn a_huge_bad_value_is_cut_short_in_the_error() {
+    let mut s = Session::new();
+    card(&mut s);
+    let junk = "é".repeat(10_000);
+    let msg = failed(s.execute("node.set", &json!({"ids": junk, "props": {"name": "renamed"}}))).unwrap_or_else(|| panic!("must fail"));
+    assert!(msg.contains("`ids` must be an array") && msg.ends_with("…)"), "{msg}");
+    assert!(msg.chars().count() < 200, "{} chars", msg.chars().count());
+}

crates/engine/src/instance_resizing_tests.rs

@@ -0,0 +1,190 @@
+//! Size and resizing overrides of layers inside instances: a layer in an instance can hug, fill or
+//! keep a fixed size of its own, and that override is kept through relayout, edits of the main
+//! (only the overridden property stays), undo, save and reopen (native and .fig), REST import,
+//! detach and reset.
+
+use base64::Engine;
+use serde_json::{Value, json};
+
+use crate::Session;
+use crate::components::tests::{copy_of, ex, healthy, idv, node};
+use figcraft_doc::*;
+
+/// A "Field" component: a 240×40 fixed horizontal auto layout frame (no padding or gap) holding
+/// "Atom", an auto layout frame hugging its 20×20 "Dot" with a min width of 100; and an instance of
+/// it. Returns (component, atom, dot, instance).
+fn field(s: &mut Session) -> (NodeId, NodeId, NodeId, NodeId) {
+    let f = idv(&ex(s, "frame.create", json!({"x": 0, "y": 0, "width": 240, "height": 40, "name": "Field"})));
+    ex(s, "node.set", json!({"id": f, "props": {"layout": "horizontal", "padding": 0, "gap": 0, "sizingH": "fixed", "sizingV": "fixed"}}));
+    let atom = idv(&ex(s, "frame.create", json!({"x": 0, "y": 0, "width": 50, "height": 20, "parent": f, "name": "Atom"})));
+    ex(
+        s,
+        "node.set",
+        json!({"id": atom, "props": {"layout": "horizontal", "padding": 0, "gap": 0, "sizingH": "hug", "sizingV": "hug", "minWidth": 100}}),
+    );
+    let dot = idv(&ex(s, "shape.rectangle", json!({"x": 0, "y": 0, "width": 20, "height": 20, "parent": atom, "props": {"name": "Dot"}})));
+    let c = idv(&ex(s, "component.create", json!({"ids": [f]})));
+    let i = idv(&ex(s, "instance.create", json!({"component": c, "x": 0, "y": 100})));
+    (c, atom, dot, i)
+}
+
+fn sizing_h(s: &Session, id: NodeId) -> Sizing {
+    node(s, id).child_layout.sizing_h
+}
+
+/// The layer named `name` below instance `inst`.
+fn named(s: &Session, inst: NodeId, name: &str) -> NodeId {
+    let doc = s.doc().unwrap();
+    doc.subtree(inst).into_iter().find(|d| *d != inst && doc.node(*d).is_some_and(|n| n.name == name)).unwrap()
+}
+
+/// The first instance in the document.
+fn instance(s: &Session) -> NodeId {
+    s.doc().unwrap().nodes().find(|n| matches!(n.kind, NodeKind::Instance { .. })).unwrap().id
+}
+
+fn open(s: &mut Session, bytes: &[u8], name: &str) {
+    ex(s, "file.open", json!({"data": base64::engine::general_purpose::STANDARD.encode(bytes), "name": name}));
+}
+
+#[test]
+fn a_layer_in_an_instance_fills_and_keeps_it_through_main_edits() {
+    let mut s = Session::new();
+    let (c, atom, dot, i) = field(&mut s);
+    let (ia, idot) = (copy_of(&s, i, atom), copy_of(&s, i, dot));
+    assert_eq!((sizing_h(&s, ia), node(&s, ia).width), (Sizing::Hug, 100.0), "hugs its dot, at least 100 wide");
+    ex(&mut s, "node.set", json!({"id": ia, "props": {"sizingH": "fill"}}));
+    assert_eq!((sizing_h(&s, ia), node(&s, ia).width), (Sizing::Fill, 240.0), "fills the instance");
+    assert!(node(&s, ia).overrides.contains("resizing"), "{:?}", node(&s, ia).overrides);
+    // Edits of the main relay the instance out: the override stays, other properties follow.
+    ex(&mut s, "node.set", json!({"id": dot, "props": {"width": 30, "fill": "#ff0000"}}));
+    assert_eq!((node(&s, ia).width, node(&s, idot).width), (240.0, 30.0));
+    ex(&mut s, "node.set", json!({"id": atom, "props": {"minWidth": 120, "fill": "#00ff00"}}));
+    assert_eq!(node(&s, atom).width, 120.0);
+    assert_eq!((sizing_h(&s, ia), node(&s, ia).width, node(&s, ia).child_layout.min_w), (Sizing::Fill, 240.0, Some(100.0)));
+    assert_eq!(node(&s, ia).fills, node(&s, atom).fills, "the fill isn't overridden: it follows the main");
+    // The main fixing its own width is the same property: the instance keeps filling.
+    ex(&mut s, "node.set", json!({"id": atom, "props": {"width": 80}}));
+    assert_eq!((sizing_h(&s, atom), sizing_h(&s, ia), node(&s, ia).width), (Sizing::Fixed, Sizing::Fill, 240.0));
+    // A structure edit of the main rebuilds the instance: the atom fills what the new layer leaves.
+    ex(&mut s, "shape.rectangle", json!({"x": 0, "y": 0, "width": 5, "height": 5, "parent": c}));
+    assert_eq!((sizing_h(&s, ia), node(&s, ia).width), (Sizing::Fill, 235.0));
+    healthy(&s);
+    // Back to the main's resizing: no override left.
+    ex(&mut s, "component.resetOverride", json!({"id": ia, "group": "resizing"}));
+    assert_eq!((sizing_h(&s, ia), node(&s, ia).width), (Sizing::Fixed, node(&s, atom).width));
+    assert!(!node(&s, ia).overrides.contains("resizing"));
+    healthy(&s);
+}
+
+#[test]
+fn size_and_resizing_overrides_undo_reset_and_detach() {
+    let mut s = Session::new();
+    let (_, atom, dot, i) = field(&mut s);
+    let (ia, idot) = (copy_of(&s, i, atom), copy_of(&s, i, dot));
+    ex(&mut s, "node.set", json!({"id": ia, "props": {"sizingH": "fill"}}));
+    ex(&mut s, "edit.undo", json!({}));
+    assert_eq!((sizing_h(&s, ia), node(&s, ia).width), (Sizing::Hug, 100.0));
+    assert!(node(&s, ia).overrides.is_empty());
+    // A fixed size of its own: kept when the main resizes the layer.
+    ex(&mut s, "node.set", json!({"id": idot, "props": {"width": 50, "height": 10}}));
+    assert!(node(&s, idot).overrides.contains("size"));
+    ex(&mut s, "node.set", json!({"id": dot, "props": {"width": 30}}));
+    assert_eq!((node(&s, idot).width, node(&s, idot).height, node(&s, dot).width), (50.0, 10.0, 30.0));
+    // A min width of its own.
+    ex(&mut s, "node.set", json!({"id": ia, "props": {"minWidth": 150}}));
+    assert_eq!(node(&s, ia).width, 150.0);
+    ex(&mut s, "node.set", json!({"id": atom, "props": {"minWidth": 90}}));
+    assert_eq!(node(&s, ia).width, 150.0);
+    healthy(&s);
+    // Reset all changes: the main's values again.
+    ex(&mut s, "component.resetInstance", json!({"ids": [i]}));
+    assert_eq!((node(&s, ia).width, node(&s, idot).width), (90.0, 30.0));
+    assert!(node(&s, ia).overrides.is_empty() && node(&s, idot).overrides.is_empty());
+    // Detaching keeps what the instance showed.
+    ex(&mut s, "node.set", json!({"id": ia, "props": {"sizingH": "fill"}}));
+    ex(&mut s, "component.detach", json!({"ids": [i]}));
+    assert_eq!((sizing_h(&s, ia), node(&s, ia).width, node(&s, ia).source), (Sizing::Fill, 240.0, None));
+    healthy(&s);
+}
+
+#[test]
+fn layers_in_instances_resize_but_keep_their_place() {
+    let mut s = Session::new();
+    let f = idv(&ex(&mut s, "frame.create", json!({"x": 0, "y": 0, "width": 200, "height": 100, "name": "Card"})));
+    let title = idv(&ex(&mut s, "text.create", json!({"text": "Hello", "x": 10, "y": 10, "parent": f, "props": {"name": "Title"}})));
+    let c = idv(&ex(&mut s, "component.create", json!({"ids": [f]})));
+    let i = idv(&ex(&mut s, "instance.create", json!({"component": c, "x": 300, "y": 0})));
+    let it = copy_of(&s, i, title);
+    ex(&mut s, "node.set", json!({"id": it, "props": {"width": 150}}));
+    assert_eq!(node(&s, it).width, 150.0, "a text box resizes");
+    assert!(node(&s, it).overrides.contains("size"));
+    // Its place, rotation and constraints are still the main's.
+    for props in [json!({"x": 50}), json!({"rotation": 15}), json!({"constraints": {"horizontal": "right"}})] {
+        assert!(s.execute("node.set", &json!({"id": it, "props": props})).is_err(), "{props} is refused");
+    }
+    // The instance's own resizing is its own, not an override.
+    ex(&mut s, "node.set", json!({"id": i, "props": {"minWidth": 100}}));
+    assert!(!node(&s, i).overrides.contains("resizing"));
+    healthy(&s);
+}
+
+#[test]
+fn resizing_overrides_survive_save_and_reopen() {
+    let mut s = Session::new();
+    let (_, atom, dot, i) = field(&mut s);
+    let (ia, idot) = (copy_of(&s, i, atom), copy_of(&s, i, dot));
+    ex(&mut s, "node.set", json!({"id": ia, "props": {"sizingH": "fill"}}));
+    ex(&mut s, "node.set", json!({"id": idot, "props": {"width": 40}}));
+    let native = figcraft_format::save_bytes(s.doc().unwrap(), None).unwrap();
+    let (fig, _) = figcraft_format::fig::export(s.doc().unwrap(), None).unwrap();
+    for (bytes, name) in [(native, "field.figcraft"), (fig, "field.fig")] {
+        let mut s = Session::new();
+        open(&mut s, &bytes, name);
+        let i = instance(&s);
+        let (ia, idot) = (named(&s, i, "Atom"), named(&s, i, "Dot"));
+        assert!(node(&s, ia).overrides.contains("resizing"), "{name}: {:?}", node(&s, ia).overrides);
+        assert!(node(&s, idot).overrides.contains("size"), "{name}: {:?}", node(&s, idot).overrides);
+        // An edit of the main relays the instance out.
+        let main = |s: &Session, id: NodeId| node(s, id).source.unwrap();
+        let (atom, dot) = (main(&s, ia), main(&s, idot));
+        ex(&mut s, "node.set", json!({"id": atom, "props": {"minWidth": 120}}));
+        ex(&mut s, "node.set", json!({"id": dot, "props": {"width": 30}}));
+        assert_eq!((sizing_h(&s, ia), node(&s, ia).width, node(&s, idot).width), (Sizing::Fill, 240.0, 40.0), "{name}");
+        healthy(&s);
+    }
+}
+
+#[test]
+fn imported_resizing_overrides_survive_relayout() {
+    let at = |x: f64, y: f64| json!([[1, 0, x], [0, 1, y]]);
+    let dot = |id: &str| json!({"id": id, "name": "Dot", "type": "RECTANGLE", "relativeTransform": at(0.0, 0.0), "size": {"x": 20, "y": 20}});
+    let atom = |id: &str, dot_id: &str, w: f64, more: Value| {
+        let mut a = json!({"id": id, "name": "Atom", "type": "FRAME", "relativeTransform": at(0.0, 0.0), "size": {"x": w, "y": 20},
+            "layoutMode": "HORIZONTAL", "primaryAxisSizingMode": "AUTO", "counterAxisSizingMode": "AUTO", "minWidth": 100, "children": [dot(dot_id)]});
+        a.as_object_mut().unwrap().extend(more.as_object().unwrap().clone());
+        a
+    };
+    let field = |id: &str, ty: &str, y: f64, kids: Value| {
+        json!({"id": id, "name": "Field", "type": ty, "relativeTransform": at(0.0, y), "size": {"x": 240, "y": 40}, "layoutMode": "HORIZONTAL",
+            "primaryAxisSizingMode": "FIXED", "counterAxisSizingMode": "FIXED", "children": kids})
+    };
+    let mut inst =
+        field("2:1", "INSTANCE", 100.0, json!([atom("I2:1;1:2", "I2:1;1:3", 240.0, json!({"layoutSizingHorizontal": "FILL", "layoutGrow": 1}))]));
+    inst["componentId"] = json!("1:1");
+    inst["overrides"] = json!([{"id": "I2:1;1:2", "overriddenFields": ["layoutSizingHorizontal", "layoutGrow"]}]);
+    let file = json!({"name": "Field", "document": {"id": "0:0", "type": "DOCUMENT", "children": [
+        {"id": "0:1", "name": "Page", "type": "CANVAS", "children": [field("1:1", "COMPONENT", 0.0, json!([atom("1:2", "1:3", 100.0, json!({}))])), inst]}
+    ]}, "components": {"1:1": {"key": "k", "name": "Field", "description": ""}}, "styles": {}});
+    let mut s = Session::new();
+    open(&mut s, file.to_string().as_bytes(), "field.json");
+    let i = instance(&s);
+    let ia = named(&s, i, "Atom");
+    assert_eq!((sizing_h(&s, ia), node(&s, ia).width), (Sizing::Fill, 240.0));
+    assert!(node(&s, ia).overrides.contains("resizing"), "{:?}", node(&s, ia).overrides);
+    // The main's first edit relays every instance out from it.
+    let main_atom = node(&s, ia).source.unwrap();
+    ex(&mut s, "node.set", json!({"id": main_atom, "props": {"minWidth": 120}}));
+    assert_eq!((sizing_h(&s, ia), node(&s, ia).width), (Sizing::Fill, 240.0));
+    healthy(&s);
+}

crates/engine/src/lib.rs

@@ -6,6 +6,8 @@
 //! change is one undo step. Pointer tools ([`tools`]) and text editing reduce to the same document
 //! edits and are journaled the same way.
 #![deny(clippy::unwrap_used, clippy::expect_used, clippy::panic, clippy::unimplemented, clippy::todo, clippy::unreachable)]
+// Tests make and inspect files directly; shipped code goes through `file_access` (clippy.toml).
+#![cfg_attr(test, allow(clippy::disallowed_methods))]
 
 pub mod al_keys;
 pub mod annotations;
@@ -24,7 +26,10 @@ pub mod dev_resources;
 pub mod devcompare;
 pub mod devinspect;
 pub mod distance;
+pub mod doc_urls;
 pub mod drop;
+pub mod file_access;
+pub mod fonts;
 pub mod guard;
 pub mod guides;
 pub mod inspect;
@@ -43,6 +48,8 @@ pub mod plugins;
 pub mod proto_run;
 pub mod rename;
 pub mod rotation_origin;
+pub mod selection_colors;
+pub mod selection_spacing;
 pub mod shape_handles;
 pub mod shapebuilder;
 pub mod snap;
@@ -369,6 +376,8 @@ pub struct DocState {
     pub guide: Option<(NodeId, usize)>,
     /// The selection's rotation origin, when moved or shown (see [`rotation_origin`]; not saved).
     pub(crate) rotation_origin: Option<rotation_origin::RotationOrigin>,
+    /// The View toggles the preferences keep were applied ([`Session::apply_view_prefs`]).
+    view_from_prefs: bool,
     /// The last duplicate while its copies are the selection: Duplicate repeats its offset (see
     /// [`cmd::edit::Duplicated`]; not saved).
     pub(crate) last_duplicate: Option<cmd::edit::Duplicated>,
@@ -430,6 +439,7 @@ impl DocState {
             focus: None,
             guide: None,
             rotation_origin: None,
+            view_from_prefs: false,
             last_duplicate: None,
         };
         st.zoom_to_fit();
@@ -609,6 +619,9 @@ pub struct Prefs {
     /// The widths of the main window's left and right panels (the interface keeps them within its
     /// limits; other windows have their own while they are open).
     pub panel_widths: (f32, f32),
+    /// The height asked for the main window's pages list, dragged at its lower edge (`None`: a
+    /// share of the panel; the interface keeps it within its limits).
+    pub pages_height: Option<f32>,
     /// The interface language: a language code ("en", "es", "pt-BR") or "system" (the OS or browser
     /// language). Languages without a catalog show English.
     pub language: String,
@@ -655,6 +668,10 @@ pub struct Prefs {
     pub home_sort: String,
     /// Which way: `"desc"` (newest first, Z to A) or `"asc"`.
     pub home_order: String,
+    /// The View menu's toggles turned on or off (rulers, pixel grid, snapping…), by command id:
+    /// files opened or made later start with them. Missing: the toggle's default.
+    #[serde(skip_serializing_if = "BTreeMap::is_empty")]
+    pub view: BTreeMap<String, bool>,
     /// Recently run actions (the Actions palette's Recents), newest first, at most
     /// [`MAX_RECENT_ACTIONS`]. Entries are `command:<id>`, `plugin:<plugin>/<command>` or
     /// `widget:<plugin>`.
@@ -677,6 +694,7 @@ impl Default for Prefs {
             show_dimensions: true,
             theme: "system".into(),
             panel_widths: (240.0, 240.0),
+            pages_height: None,
             language: "system".into(),
             user_name: cmd::comment::DEFAULT_AUTHOR.into(),
             reduce_motion: false,
@@ -692,6 +710,7 @@ impl Default for Prefs {
             home_views: BTreeMap::new(),
             home_sort: "modified".into(),
             home_order: "desc".into(),
+            view: BTreeMap::new(),
             recent_actions: Vec::new(),
         }
     }
@@ -844,6 +863,14 @@ impl Session {
         s
     }
 
+    /// Files new to the session start with the View toggles the preferences keep.
+    pub fn apply_view_prefs(&mut self) {
+        for ds in self.docs.iter_mut().filter(|d| !d.view_from_prefs) {
+            cmd::view::apply_kept(&self.prefs, &mut ds.view);
+            ds.view_from_prefs = true;
+        }
+    }
+
     pub fn ds(&self) -> Result<&DocState> {
         self.docs.get(self.active).ok_or(EngineError::NoDocument)
     }
@@ -885,6 +912,7 @@ impl Session {
             return Err(EngineError::Disabled(id.into(), "leave the live session before reverting to the saved file".into()));
         }
         branches::sync(self);
+        self.apply_view_prefs();
         if textpreview::COMMANDS.contains(&id) {
             // A live preview is no edit: no undo step, normalisation or rollback here.
             let r = guard::run(id, || (spec.run)(self, params));
@@ -905,10 +933,12 @@ impl Session {
         let result = guard::run(id, || (spec.run)(self, params))
             .and_then(|v| self.check_instance_structure(id, &before).map(|()| v))
             .and_then(|v| self.check_preview(id, &before).map(|()| v))
-            .and_then(|v| self.check_live_access(id, &before).map(|()| v));
+            .and_then(|v| self.check_live_access(id, &before).map(|()| v))
+            .and_then(|v| self.check_finite_geometry(id, &before).map(|()| v));
         match &result {
             Ok(_) => {
                 self.after_command(spec, before);
+                self.apply_view_prefs();
                 if spec.history && id != "edit.repeat" {
                     self.last_command = Some((id.to_string(), params.clone()));
                 }
@@ -947,6 +977,22 @@ impl Session {
         Err(EngineError::Disabled(id.to_string(), PREVIEW_READ_ONLY.into()))
     }
 
+    /// A layer's position and size stay finite: infinity and NaN are written as `null`, so a file
+    /// holding them saves but can't be reopened. Refuse such an edit (it is rolled back).
+    fn check_finite_geometry(&self, id: &str, before: &Option<(Arc<Document>, Vec<NodeId>, NodeId, u64)>) -> Result<()> {
+        let Some((bdoc, _, _, uid)) = before else { return Ok(()) };
+        let Some(ds) = self.docs.iter().find(|d| d.uid == *uid) else { return Ok(()) };
+        if Arc::ptr_eq(&ds.doc, bdoc) {
+            return Ok(());
+        }
+        let broken = |n: &Node| !(n.transform.as_coeffs().iter().all(|c| c.is_finite()) && n.width.is_finite() && n.height.is_finite());
+        let untouched = |n: &Node| bdoc.node_arc(n.id).zip(ds.doc.node_arc(n.id)).is_some_and(|(a, b)| Arc::ptr_eq(a, b));
+        match ds.doc.nodes().find(|n| broken(n) && !untouched(n)) {
+            Some(n) => Err(bad(id, format!("\"{}\" would get a position or size beyond the number range", n.name))),
+            None => Ok(()),
+        }
+    }
+
     /// A live session's document you may only view (or that is on its way to a server) is
     /// read-only: refuse an edit (it is rolled back).
     fn check_live_access(&self, id: &str, before: &Option<(Arc<Document>, Vec<NodeId>, NodeId, u64)>) -> Result<()> {
@@ -1166,13 +1212,22 @@ impl Session {
         self.grouped(label, |s| {
             let mut results: Vec<Value> = Vec::with_capacity(cmds.len());
             for (step, (id, p)) in cmds.iter().enumerate() {
-                let p = if id == "command.batch" { p.clone() } else { resolve_step_refs(p, &results, step, 0)? };
-                results.push(s.execute(id, &p)?);
+                let v = s.batch_step(&results, step, id, p)?;
+                results.push(v);
             }
             Ok(results)
         })
     }
 
+    /// One step of a batch: `{"$step": n}` in `params` resolves against `results` (the results of
+    /// the steps before it), then the command runs. [`Session::batch`] runs a list of these as one
+    /// undo step; a caller with its own list — the CLI's script runner — uses this so its steps
+    /// resolve `$step` the same way, inside its own [`Session::grouped`].
+    pub fn batch_step(&mut self, results: &[Value], step: usize, cmd: &str, params: &Value) -> Result<Value> {
+        let p = if cmd == "command.batch" { params.clone() } else { resolve_step_refs(params, results, step, 0)? };
+        self.execute(cmd, &p)
+    }
+
     /// Run `f` as one undo step called `label`: the commands it executes push no steps of their
     /// own, and when it fails the documents stay at their group-start state.
     pub fn grouped<T>(&mut self, label: &str, f: impl FnOnce(&mut Self) -> Result<T>) -> Result<T> {
@@ -1499,6 +1554,8 @@ mod binding_lists_tests;
 #[cfg(test)]
 mod booleans_tests;
 #[cfg(test)]
+mod bound_alpha_tests;
+#[cfg(test)]
 mod branch_tests;
 #[cfg(test)]
 mod branch_versions_tests;
@@ -1541,6 +1598,8 @@ mod devfocus_tests;
 #[cfg(test)]
 mod devinspect_tests;
 #[cfg(test)]
+mod doc_urls_tests;
+#[cfg(test)]
 mod double_click_tests;
 #[cfg(test)]
 mod draw_tools_tests;
@@ -1561,6 +1620,8 @@ mod fig_export_tests;
 #[cfg(test)]
 mod fig_import_tests;
 #[cfg(test)]
+mod finite_geometry_tests;
+#[cfg(test)]
 mod frame_guides_tests;
 #[cfg(test)]
 mod frame_label_tests;
@@ -1583,18 +1644,24 @@ mod html_codegen_tests;
 #[cfg(test)]
 mod huge_stroke_tests;
 #[cfg(test)]
+mod id_params_behaviour_tests;
+#[cfg(test)]
 mod import_export_tests;
 #[cfg(test)]
 mod import_journal_tests;
 #[cfg(test)]
 mod inspect_behaviour_tests;
 #[cfg(test)]
+mod instance_resizing_tests;
+#[cfg(test)]
 mod interaction_rollback_tests;
 #[cfg(test)]
 mod invite_links_tests;
 #[cfg(test)]
 mod keymap_tests;
 #[cfg(test)]
+mod library_path_tests;
+#[cfg(test)]
 mod library_range_styles_tests;
 #[cfg(test)]
 mod library_variables_tests;
@@ -1621,16 +1688,22 @@ mod menu_gaps_tests;
 #[cfg(test)]
 mod nested_override_tests;
 #[cfg(test)]
+mod node_set_refusals_tests;
+#[cfg(test)]
 mod online_tests;
 #[cfg(test)]
 mod open_issues_tests;
 #[cfg(test)]
 mod outline_options_tests;
 #[cfg(test)]
+mod page_clipboard_tests;
+#[cfg(test)]
 mod page_copy_navigation_tests;
 #[cfg(test)]
 mod page_target_tests;
 #[cfg(test)]
+mod paint_index_tests;
+#[cfg(test)]
 mod paint_reorder_tests;
 #[cfg(test)]
 mod paint_tests;
@@ -1639,6 +1712,8 @@ mod panels_behaviour_tests;
 #[cfg(test)]
 mod pdf_print_tests;
 #[cfg(test)]
+mod pen_end_tests;
+#[cfg(test)]
 mod pen_overlay_tests;
 #[cfg(test)]
 mod pixel_preview_tests;
@@ -1671,6 +1746,8 @@ mod proto_run_tests;
 #[cfg(test)]
 mod proto_tail_tests;
 #[cfg(test)]
+mod rest_slot_tests;
+#[cfg(test)]
 mod retained_walk_tests;
 #[cfg(test)]
 mod rotated_guides_tests;
@@ -1743,6 +1820,8 @@ mod variables_behaviour_tests;
 #[cfg(test)]
 mod variables_editor_tests;
 #[cfg(test)]
+mod variables_import_shapes_tests;
+#[cfg(test)]
 mod variables_io_tests;
 #[cfg(test)]
 mod vector_behaviour_tests;
@@ -1758,3 +1837,6 @@ mod version_tests;
 mod view_behaviour_tests;
 #[cfg(test)]
 mod widgets_tests;
+
+#[cfg(test)]
+mod selection_spacing_tests;

crates/engine/src/library.rs

@@ -449,9 +449,27 @@ struct Stamp {
 #[derive(Clone, Debug)]
 struct Entry {
     stamp: Option<Stamp>,
+    /// When the file was read: a stamp only proves the file unchanged once its modification time
+    /// is safely older than that, since file systems keep the time in coarse ticks.
+    read_at: Option<std::time::SystemTime>,
     result: std::result::Result<Arc<PublishedLibrary>, String>,
 }
 
+/// How far a file's modification time must lie before its read for the stamp to be trusted.
+const RACY_STAMP: std::time::Duration = std::time::Duration::from_secs(2);
+
+impl Entry {
+    /// A file stamped in the future (clock skew, unpacked archives) never settles: it is re-read on
+    /// every load until the clock passes it.
+    fn still_valid(&self, now: &Stamp) -> bool {
+        let settled = match (now.modified, self.read_at) {
+            (Some(modified), Some(read_at)) => modified.checked_add(RACY_STAMP).is_some_and(|t| t < read_at),
+            _ => false,
+        };
+        settled && self.stamp.as_ref() == Some(now)
+    }
+}
+
 /// Library files read by a session, by path (re-read when they change on disk).
 #[derive(Clone, Debug, Default)]
 pub struct Cache {
@@ -481,10 +499,11 @@ impl Cache {
             return Err(EngineError::Other(format!("{path} is too large to use as a library (the limit is {} MB)", max_bytes / 1024 / 1024)));
         }
         if let (Some(e), Ok(st)) = (self.entries.get(path), &stamp)
-            && e.stamp.as_ref() == Some(st)
+            && e.still_valid(st)
         {
             return e.result.clone().map_err(EngineError::Other);
         }
+        let read_at = now();
         let result = match &stamp {
             Ok(_) => read_file(path).map(Arc::new),
             Err(e) => Err(e.clone()),
@@ -492,7 +511,7 @@ impl Cache {
         if self.entries.len() >= MAX_CACHED && !self.entries.contains_key(path) {
             self.entries.clear();
         }
-        self.entries.insert(path.to_string(), Entry { stamp: stamp.ok(), result: result.clone() });
+        self.entries.insert(path.to_string(), Entry { stamp: stamp.ok(), read_at, result: result.clone() });
         result.map_err(EngineError::Other)
     }
 
@@ -506,13 +525,23 @@ impl Cache {
         if self.entries.len() >= MAX_CACHED && !self.entries.contains_key(path) {
             self.entries.clear();
         }
-        self.entries.insert(path.to_string(), Entry { stamp: None, result });
+        self.entries.insert(path.to_string(), Entry { stamp: None, read_at: None, result });
     }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
+fn now() -> Option<std::time::SystemTime> {
+    Some(std::time::SystemTime::now())
+}
+
+#[cfg(target_arch = "wasm32")]
+fn now() -> Option<std::time::SystemTime> {
+    None
+}
+
 #[cfg(not(target_arch = "wasm32"))]
 fn stat(path: &str) -> std::result::Result<Stamp, String> {
-    let m = std::fs::metadata(path).map_err(|e| format!("{path}: {e}"))?;
+    let m = crate::file_access::metadata(path).map_err(|e| e.to_string())?;
     if !m.is_file() {
         return Err(format!("{path} is not a file"));
     }
@@ -526,7 +555,7 @@ fn stat(_path: &str) -> std::result::Result<Stamp, String> {
 
 #[cfg(not(target_arch = "wasm32"))]
 fn read_file(path: &str) -> std::result::Result<PublishedLibrary, String> {
-    let f = std::fs::File::open(path).map_err(|e| format!("{path}: {e}"))?;
+    let f = crate::file_access::open(path).map_err(|e| e.to_string())?;
     match figcraft_format::read_library(std::io::BufReader::new(f)) {
         Ok(Some(lib)) => Ok(lib),
         Ok(None) => Err(format!("{path} has no published library: open it and publish it first (Libraries ▸ Publish library…)")),

crates/engine/src/library_path_tests.rs

@@ -0,0 +1,30 @@
+//! A library link is stored in the document, so it is followed only on this computer
+//! ([`crate::library_server`]): a path on another server would make opening someone else's file
+//! contact that server, and on Windows send the credentials of whoever opened it.
+
+use crate::Session;
+
+#[test]
+fn a_library_is_opened_only_from_this_computer() {
+    let mut s = Session::new();
+    for path in [
+        r"\\attacker.example\share\lib.figcraft",
+        "//attacker.example/share/lib.figcraft",
+        "file://attacker.example/share/lib.figcraft",
+        r"\\?\UNC\attacker.example\share\lib.figcraft",
+        r"\\.\pipe\lib",
+        "https://attacker.example/lib.figcraft",
+    ] {
+        let e = s.fetch_library(path, false).expect_err(&format!("{path} must be refused"));
+        assert!(e.to_string().contains("only from this computer"), "{path}: {e}");
+    }
+}
+
+#[test]
+fn a_local_library_path_is_still_followed() {
+    let mut s = Session::new();
+    // Refused for being absent, not for where it is: the gate let it through.
+    let missing = std::env::temp_dir().join("figcraft-no-such-library.figcraft");
+    let e = s.fetch_library(&missing.to_string_lossy(), false).expect_err("the file does not exist");
+    assert!(!e.to_string().contains("only from this computer"), "a local path must not be refused as remote: {e}");
+}

crates/engine/src/library_server.rs

@@ -129,6 +129,13 @@ impl Session {
     /// document uses the library.
     pub fn fetch_library(&mut self, path: &str, fresh: bool) -> Result<Arc<PublishedLibrary>> {
         if !is_server_link(path) {
+            // A library link is stored in the document, so opening someone else's file would
+            // otherwise reach whatever path it names. Only a path on this computer is followed: a
+            // network share would make opening a document contact that server, and on Windows
+            // send the credentials of whoever opened it.
+            if !craft_docpath::is_local(path) {
+                return Err(EngineError::Other(format!("{path}: a library is opened only from this computer")));
+            }
             return self.libraries.load(path);
         }
         let have = match self.libraries.cached(path) {

crates/engine/src/library_tests.rs

@@ -445,3 +445,21 @@ fn library_survives_saving_with_versions() {
     healthy(&user);
     let _ = std::fs::remove_dir_all(&d);
 }
+
+#[test]
+fn a_file_stamp_from_the_moment_it_was_read_does_not_prove_it_unchanged() {
+    use std::time::{Duration, SystemTime};
+    let read_at = SystemTime::now();
+    let entry = |modified: SystemTime| Entry {
+        stamp: Some(Stamp { len: 10, modified: Some(modified) }),
+        read_at: Some(read_at),
+        result: Err("unused".into()),
+    };
+    // Written in the same coarse tick as the read: a same-length rewrite would keep this stamp.
+    let fresh = entry(read_at);
+    assert!(!fresh.still_valid(&Stamp { len: 10, modified: Some(read_at) }));
+    // Written well before the read: an unchanged stamp means an unchanged file.
+    let old = read_at - Duration::from_secs(10);
+    assert!(entry(old).still_valid(&Stamp { len: 10, modified: Some(old) }));
+    assert!(!entry(old).still_valid(&Stamp { len: 11, modified: Some(old) }));
+}

crates/engine/src/node_set_refusals_tests.rs

@@ -0,0 +1,95 @@
+//! `node.set` doesn't store what can't apply: auto layout keys go only to layers that can have auto
+//! layout (the others are named in `warnings`, and with none of them the call is refused), and a
+//! `fontStyle` the family lacks says which face draws instead.
+
+use serde_json::{Value, json};
+
+use crate::{EngineError, Session};
+
+fn ex(s: &mut Session, cmd: &str, p: Value) -> Value {
+    s.execute(cmd, &p).unwrap_or_else(|e| panic!("{cmd}: {e}"))
+}
+
+fn id(v: &Value) -> crate::NodeId {
+    crate::params::id_of(v).unwrap()
+}
+
+fn bad_msg(r: crate::Result<Value>) -> String {
+    match r {
+        Err(EngineError::BadParams { msg, .. }) => msg,
+        other => panic!("expected BadParams, got {other:?}"),
+    }
+}
+
+#[test]
+fn auto_layout_keys_on_layers_without_auto_layout_are_refused() {
+    let mut s = Session::new();
+    let t = id(&ex(&mut s, "node.create", json!({"type": "text", "text": "Hi"}))["id"]);
+    let r = id(&ex(&mut s, "node.create", json!({"type": "rectangle"}))["id"]);
+    for (target, key, value) in [(t, "gap", json!(8)), (r, "padding", json!(4)), (t, "mainAlign", json!("center")), (r, "wrap", json!(true))] {
+        let msg = bad_msg(s.execute("node.set", &json!({"ids": [target], "props": {key: value}})));
+        assert!(msg.contains(key) && msg.contains("auto layout"), "{msg}");
+        assert!(s.doc().unwrap().node(target).unwrap().layout.is_none(), "no hidden auto layout on {target}");
+    }
+    // Frames still take them, with or without a layout mode first.
+    let f = id(&ex(&mut s, "node.create", json!({"type": "frame"}))["id"]);
+    let out = ex(&mut s, "node.set", json!({"ids": [f], "props": {"gap": 8, "padding": 4}}));
+    assert_eq!(s.doc().unwrap().node(f).unwrap().layout.as_ref().map(|l| l.gap), Some(8.0));
+    assert!(out.get("warnings").is_none(), "{out}");
+}
+
+#[test]
+fn with_several_layers_the_frames_take_auto_layout_keys_and_the_others_are_named() {
+    let mut s = Session::new();
+    let f = id(&ex(&mut s, "node.create", json!({"type": "frame", "name": "Card"}))["id"]);
+    let t = id(&ex(&mut s, "node.create", json!({"type": "text", "text": "Hi", "name": "Title"}))["id"]);
+    let out = ex(&mut s, "node.set", json!({"ids": [f, t], "props": {"gap": 8, "opacity": 0.5}}));
+    let doc = s.doc().unwrap();
+    assert_eq!(doc.node(f).unwrap().layout.as_ref().map(|l| l.gap), Some(8.0));
+    assert!(doc.node(t).unwrap().layout.is_none(), "no hidden auto layout on the text");
+    assert_eq!(doc.node(t).unwrap().opacity, 0.5, "the text still gets the other keys");
+    let w = out["warnings"][0].as_str().unwrap();
+    assert!(w.contains("`gap`") && w.contains(&format!("{t} “Title”")) && w.contains("TEXT"), "{w}");
+    // One undo step for all of it.
+    ex(&mut s, "edit.undo", json!({}));
+    assert!(s.doc().unwrap().node(f).unwrap().layout.as_ref().is_none_or(|l| l.gap != 8.0));
+}
+
+#[test]
+fn a_font_style_draws_in_the_nearest_face_and_says_so_when_it_differs() {
+    figcraft_text::scan_system_fonts();
+    // Any installed family with a regular and a bold face and nothing heavier (CI machines differ).
+    let pick = figcraft_text::family_names().into_iter().find_map(|f| {
+        let st = figcraft_text::family_styles(&f);
+        let has = |w: u16| st.iter().any(|x| figcraft_doc::style_weight(x) == w && !x.to_lowercase().contains("italic"));
+        (has(400) && has(700) && !st.iter().any(|x| figcraft_doc::style_weight(x) > 700)).then_some((f, st))
+    });
+    let Some((family, styles)) = pick else { return };
+    let mut s = Session::new();
+    let t = id(&ex(&mut s, "node.create", json!({"type": "text", "text": "Hi", "props": {"fontFamily": family}}))["id"]);
+    let set = |s: &mut Session, style: &str| ex(s, "node.set", json!({"ids": [t], "props": {"fontStyle": style}}));
+    // Any spelling of a style it has, and names that resolve to the weight they ask for, say nothing.
+    let bold = styles.iter().find(|x| figcraft_doc::style_weight(x) == 700).unwrap().clone();
+    for style in [bold.clone(), bold.to_uppercase(), bold.replace(' ', ""), "Roman".into(), "Normal".into()] {
+        let out = set(&mut s, &style);
+        assert!(out.get("warnings").is_none(), "{style}: {out}");
+    }
+    // A heavier weight than the family has applies (as a text layer resolves it) and says which face draws.
+    let out = set(&mut s, "Black");
+    let w = out["warnings"][0].as_str().unwrap();
+    assert!(w.contains(&family) && w.contains("`Black`") && w.contains("nearest"), "{w}");
+    assert_eq!(s.doc().unwrap().node(t).unwrap().kind.text().unwrap().spans()[0].2.font_style, "Black");
+    // A family that isn't installed keeps any style name without a word (files from elsewhere name theirs).
+    let out = ex(&mut s, "node.set", json!({"ids": [t], "props": {"fontFamily": "No Such Family 7f3a", "fontStyle": "Hairline"}}));
+    assert!(out.get("warnings").is_none(), "{out}");
+}
+
+#[test]
+fn a_refused_call_changes_nothing() {
+    let mut s = Session::new();
+    let t = id(&ex(&mut s, "node.create", json!({"type": "text", "text": "Hi"}))["id"]);
+    let before = s.doc().unwrap().node(t).unwrap().fills.clone();
+    // `fill` comes before `gap` (keys apply in order), so this checks the rollback.
+    assert!(s.execute("node.set", &json!({"ids": [t], "props": {"fill": "#FF0000", "gap": 8}})).is_err());
+    assert_eq!(s.doc().unwrap().node(t).unwrap().fills, before);
+}

crates/engine/src/page_clipboard_tests.rs

@@ -0,0 +1,36 @@
+//! `edit.copy` / `edit.cut` skip pages (they aren't layers and can't be pasted), and refuse a
+//! selection of only pages under their own command id.
+
+use serde_json::json;
+
+use crate::{EngineError, Session};
+
+#[test]
+fn copy_and_cut_ignore_pages_so_paste_keeps_the_document_valid() {
+    for cmd in ["edit.copy", "edit.cut"] {
+        let mut s = Session::new();
+        let page = s.page().unwrap();
+        s.execute("shape.rectangle", &json!({"x": 0, "y": 0, "width": 10, "height": 10})).unwrap();
+        match s.execute(cmd, &json!({"ids": [page.0]})) {
+            Err(EngineError::Disabled(id, _)) => assert_eq!(id, cmd),
+            r => panic!("{cmd} on a page: {r:?}"),
+        }
+        let _ = s.execute("edit.paste", &json!({}));
+        let doc = s.doc().unwrap();
+        assert!(doc.validate().is_empty(), "{cmd}: {:?}", doc.validate());
+        assert!(doc.node(page).is_some(), "{cmd} removed the page");
+    }
+}
+
+#[test]
+fn cut_of_a_page_and_a_layer_moves_only_the_layer() {
+    let mut s = Session::new();
+    let page = s.page().unwrap();
+    let r = s.execute("shape.rectangle", &json!({"x": 0, "y": 0, "width": 10, "height": 10})).unwrap();
+    let rect = crate::params::id_of(&r["id"]).unwrap();
+    s.execute("edit.cut", &json!({"ids": [page.0, rect.0]})).unwrap();
+    assert!(s.doc().unwrap().node(page).is_some());
+    assert!(s.doc().unwrap().node(rect).is_none());
+    s.execute("edit.paste", &json!({})).unwrap();
+    assert!(s.doc().unwrap().validate().is_empty());
+}

crates/engine/src/paint_index_tests.rs

@@ -0,0 +1,39 @@
+//! `fill.set` / `stroke.set` reject a negative, fractional or non-finite `index` instead of
+//! clamping or truncating it onto another paint (like `fill.remove` / `stroke.remove`).
+
+use figcraft_doc::NodeId;
+use serde_json::{Value, json};
+
+use crate::Session;
+
+fn ex(s: &mut Session, cmd: &str, p: Value) -> Value {
+    s.execute(cmd, &p).unwrap_or_else(|e| panic!("{cmd} {p}: {e}"))
+}
+
+fn paints(s: &Session, id: NodeId) -> String {
+    let n = s.doc().unwrap().node(id).unwrap();
+    format!("{:?} {:?}", n.fills, n.strokes)
+}
+
+#[test]
+fn paint_set_rejects_bad_index_and_leaves_the_paints_alone() {
+    let mut s = Session::new();
+    let r = NodeId(ex(&mut s, "shape.rectangle", json!({"x": 0, "y": 0, "width": 10, "height": 10}))["id"].as_u64().unwrap());
+    for add in ["fill.add", "stroke.add"] {
+        for c in ["#0000FF", "#FFFF00"] {
+            ex(&mut s, add, json!({"ids": [r], "color": c}));
+        }
+    }
+    let before = paints(&s, r);
+    for cmd in ["fill.set", "stroke.set"] {
+        for bad in [json!(-1), json!(0.5), json!(1.9), json!("-1"), json!("1.5"), json!("NaN"), json!("inf"), json!("abc")] {
+            let res = s.execute(cmd, &json!({"ids": [r], "index": bad, "color": "#FF0000"}));
+            assert!(res.is_err(), "{cmd} index {bad} was accepted: {res:?}");
+            assert_eq!(paints(&s, r), before, "{cmd} index {bad} changed the document");
+        }
+        ex(&mut s, cmd, json!({"ids": [r], "index": 1, "color": "#FF0000"}));
+        assert_ne!(paints(&s, r), before, "{cmd} with a valid index still edits");
+        ex(&mut s, "edit.undo", json!({}));
+        assert_eq!(paints(&s, r), before);
+    }
+}

crates/engine/src/params.rs

@@ -88,6 +88,36 @@ pub fn req_id(cmd: &str, p: &Value, key: &str) -> Result<NodeId> {
     id(p, key).ok_or_else(|| bad(cmd, format!("`{key}` must be a node id")))
 }
 
+/// The offending value for an error message, cut to a few dozen characters so a huge param
+/// doesn't end up in the error whole.
+fn shown(v: &Value) -> String {
+    const MAX: usize = 40;
+    let text = v.to_string();
+    match text.char_indices().nth(MAX) {
+        Some((cut, _)) => format!("{}…", &text[..cut]),
+        None => text,
+    }
+}
+
+/// `key` when it is there: a layer id, or an error naming it. Missing and `null` mean "none", so a
+/// command can tell "no parent given" (use the page) from "a parent was given that isn't an id" —
+/// which is a mistake, not the default. Without this, `{"$step": 0}` reaching a param that isn't
+/// resolved yet silently becomes "no parent" and the layer lands on the page.
+pub fn opt_id(cmd: &str, p: &Value, key: &str) -> Result<Option<NodeId>> {
+    match get(p, key) {
+        None | Some(Value::Null) => Ok(None),
+        Some(v) => id_of(v).map(Some).ok_or_else(|| bad(cmd, format!("`{key}` must be a node id (got {})", shown(v)))),
+    }
+}
+
+/// `key` when it is there: a whole, non-negative number, or an error. Missing means "none".
+pub fn opt_index(cmd: &str, p: &Value, key: &str) -> Result<Option<usize>> {
+    match get(p, key) {
+        None | Some(Value::Null) => Ok(None),
+        Some(_) => req_index(cmd, p, key).map(Some),
+    }
+}
+
 /// `ids` (array), `id` (single), or the current selection.
 pub fn targets(s: &Session, p: &Value) -> Vec<NodeId> {
     if let Some(Value::Array(a)) = get(p, "ids") {
@@ -99,8 +129,25 @@ pub fn targets(s: &Session, p: &Value) -> Vec<NodeId> {
     s.selection()
 }
 
-/// Like [`targets`] but an empty result is an error.
+/// Like [`targets`] but an unparseable `ids` entry, an unparseable `id`, or an empty result is an
+/// error: naming something that isn't a layer is a mistake, not an empty selection. An explicit
+/// `null` says the same as leaving the key out.
 pub fn req_targets(cmd: &str, s: &Session, p: &Value) -> Result<Vec<NodeId>> {
+    match get(p, "ids") {
+        Some(Value::Array(a)) => {
+            if let Some(v) = a.iter().find(|v| id_of(v).is_none()) {
+                return Err(bad(cmd, format!("`ids`: every entry must be a node id (got {})", shown(v))));
+            }
+        }
+        Some(Value::Null) | None => {
+            if let Some(v) = get(p, "id").filter(|v| !v.is_null())
+                && id_of(v).is_none()
+            {
+                return Err(bad(cmd, format!("`id` must be a node id (got {})", shown(v))));
+            }
+        }
+        Some(v) => return Err(bad(cmd, format!("`ids` must be an array (got {})", shown(v)))),
+    }
     let t = targets(s, p);
     if t.is_empty() {
         return Err(EngineError::Disabled(cmd.to_string(), "nothing is selected (pass `ids`)".into()));

crates/engine/src/pen_end_tests.rs

@@ -0,0 +1,72 @@
+//! Ending a pen path with Escape or Enter (#760): the path's vector stays in edit mode with the pen,
+//! so the next path is drawn into the same layer; another Escape leaves edit mode.
+
+use crate::Session;
+use crate::tools::{PointerEvent, PointerKind, ToolId};
+use crate::vectoredit::VTool;
+use figcraft_doc::NodeKind;
+
+fn click(s: &mut Session, x: f64, y: f64) {
+    for kind in [PointerKind::Down, PointerKind::Up] {
+        s.pointer(&PointerEvent::at(kind, x, y, 1.0)).unwrap();
+    }
+}
+
+fn layers(s: &Session) -> usize {
+    s.doc().unwrap().node(s.page().unwrap()).unwrap().children.len()
+}
+
+/// (points, segments) of vector `id`.
+fn shape(s: &Session, id: figcraft_doc::NodeId) -> (usize, usize) {
+    match &s.doc().unwrap().node(id).unwrap().kind {
+        NodeKind::Vector { network } => (network.vertices.len(), network.segments.len()),
+        k => panic!("not a vector: {k:?}"),
+    }
+}
+
+/// A two-point pen path, ended with `end`.
+fn drawn(end: fn(&mut Session)) -> (Session, figcraft_doc::NodeId) {
+    let mut s = Session::new();
+    s.set_tool(ToolId::Pen);
+    click(&mut s, 100.0, 100.0);
+    click(&mut s, 200.0, 100.0);
+    let id = s.tool.pen.as_ref().and_then(|p| p.id).unwrap();
+    let undo = s.undo_depth().0;
+    end(&mut s);
+    assert!(s.tool.pen.is_none(), "the path ended");
+    assert_eq!(s.undo_depth().0, undo + 1, "the path is one undo step");
+    let ve = s.ds().unwrap().vector_edit.clone().expect("still editing the vector");
+    assert_eq!((ve.id, ve.tool, ve.anchor), (id, VTool::Pen, None), "the pen, with no open end");
+    (s, id)
+}
+
+#[test]
+fn escape_and_enter_keep_the_vector_in_edit_mode_with_the_pen() {
+    // Escape, and Enter (its key runs `pen_end`).
+    let ends: [fn(&mut Session); 2] = [|s| s.escape().unwrap(), |s| s.pen_end().unwrap()];
+    for end in ends {
+        let (mut s, id) = drawn(end);
+        // The next path goes into the same layer, unconnected to the first.
+        click(&mut s, 100.0, 300.0);
+        click(&mut s, 200.0, 300.0);
+        assert_eq!(layers(&s), 1, "no new layer");
+        assert_eq!(shape(&s, id), (4, 2), "two separate paths in one vector network");
+        // Escape ends that path, the next one leaves edit mode.
+        s.escape().unwrap();
+        assert!(s.ds().unwrap().vector_edit.is_some());
+        s.escape().unwrap();
+        assert!(s.ds().unwrap().vector_edit.is_none(), "the second Escape leaves edit mode");
+        assert_eq!(s.ds().unwrap().selection, vec![id]);
+    }
+}
+
+#[test]
+fn escape_before_a_segment_leaves_nothing_to_edit() {
+    let mut s = Session::new();
+    s.set_tool(ToolId::Pen);
+    click(&mut s, 100.0, 100.0);
+    s.escape().unwrap();
+    assert!(s.tool.pen.is_none());
+    assert!(s.ds().unwrap().vector_edit.is_none());
+    assert_eq!(layers(&s), 0);
+}

crates/engine/src/playground.rs

@@ -75,7 +75,7 @@ pub fn specs() -> Vec<CommandSpec> {
             if let Some(path) = string(p, "path") {
                 let scale = num(p, "scale").filter(|k| k.is_finite()).map_or(2.0, |k| k.clamp(0.01, 16.0));
                 let png = crate::cmd::file::export_bytes(&copy, &[inst], ExportFormat::Png, scale)?;
-                std::fs::write(&path, png).map_err(|e| EngineError::Other(format!("{path}: {e}")))?;
+                crate::file_access::write(&path, &png)?;
                 out["path"] = json!(path);
             }
             Ok(out)

crates/engine/src/plugin_directory.rs

@@ -147,6 +147,9 @@ fn install(s: &mut Session, p: &Value) -> Result<Value> {
 /// Keep an installed plugin's files in its own folder under the install folder (named by the hash
 /// of its id, so no id reaches the file system), its module renamed; the manifest's path. Without
 /// an install folder (the browser, the CLI and tests) the plugin lasts for the session.
+// The install folder is the app's own (set by the desktop app, never by a command), so automation
+// roots don't apply to it.
+#[allow(clippy::disallowed_methods)]
 fn save(s: &Session, m: &mut Manifest, b: &Bundle) -> std::result::Result<Option<String>, String> {
     let Some(root) = s.plugins.install_dir.clone() else { return Ok(None) };
     #[cfg(not(target_arch = "wasm32"))]
@@ -189,6 +192,7 @@ fn save(s: &Session, m: &mut Manifest, b: &Bundle) -> std::result::Result<Option
 }
 
 /// Delete the folder of a plugin installed from a directory (only one inside the install folder).
+#[allow(clippy::disallowed_methods)]
 pub(crate) fn delete_installed(s: &Session, p: &InstalledPlugin) {
     #[cfg(not(target_arch = "wasm32"))]
     if let (Some(_), Some(path), Some(root)) = (&p.source, &p.path, &s.plugins.install_dir)
@@ -208,7 +212,7 @@ pub(crate) fn delete_installed(s: &Session, p: &InstalledPlugin) {
 fn bundle_from_disk(cmd: &str, path: &str) -> Result<Bundle> {
     use crate::plugins::{module_file, read_file};
     let mut file = std::path::PathBuf::from(crate::library::absolute_path(path.trim()));
-    if file.is_dir() {
+    if crate::file_access::is_dir(&file) {
         file.push(MANIFEST_FILE);
     }
     let text =
@@ -217,9 +221,12 @@ fn bundle_from_disk(cmd: &str, path: &str) -> Result<Bundle> {
     let wasm = module_file(&file, &m)?;
     let mut assets = Vec::new();
     let dir = file.parent().map(|d| d.join(ASSETS));
-    if let Some(entries) = dir.as_ref().and_then(|d| std::fs::read_dir(d).ok()) {
-        let mut names: Vec<(String, std::path::PathBuf)> =
-            entries.flatten().filter(|e| e.path().is_file()).map(|e| (e.file_name().to_string_lossy().into_owned(), e.path())).collect();
+    if let Some(entries) = dir.as_ref().and_then(|d| crate::file_access::read_dir(d).ok()) {
+        let mut names: Vec<(String, std::path::PathBuf)> = entries
+            .into_iter()
+            .filter(|p| crate::file_access::metadata(p).is_ok_and(|m| m.is_file()))
+            .map(|p| (p.file_name().map(|n| n.to_string_lossy().into_owned()).unwrap_or_default(), p))
+            .collect();
         names.sort();
         if names.len() > MAX_ASSETS {
             return Err(bad(cmd, format!("a plugin's assets folder holds at most {MAX_ASSETS} files")));

crates/engine/src/plugins.rs

@@ -251,12 +251,11 @@ pub(crate) fn installed<'a>(s: &'a Session, cmd: &str, id: &str) -> Result<&'a I
 /// Read a file of at most `max` bytes.
 #[cfg(not(target_arch = "wasm32"))]
 pub(crate) fn read_file(path: &std::path::Path, max: usize) -> Result<Vec<u8>> {
-    let shown = path.display();
-    let meta = std::fs::metadata(path).map_err(|e| EngineError::Other(format!("{shown}: {e}")))?;
+    let meta = crate::file_access::metadata(path)?;
     if !meta.is_file() || meta.len() > max as u64 {
-        return Err(EngineError::Other(format!("{shown}: not a file of at most {} KB", max / 1024)));
+        return Err(EngineError::Other(format!("{}: not a file of at most {} KB", path.display(), max / 1024)));
     }
-    std::fs::read(path).map_err(|e| EngineError::Other(format!("{shown}: {e}")))
+    crate::file_access::read(path)
 }
 
 /// The manifest at `path` (the file, or the folder holding `figcraft-plugin.json`), its absolute
@@ -264,7 +263,7 @@ pub(crate) fn read_file(path: &std::path::Path, max: usize) -> Result<Vec<u8>> {
 #[cfg(not(target_arch = "wasm32"))]
 fn load_from_disk(cmd: &str, path: &str) -> Result<(Manifest, String, Vec<u8>)> {
     let mut file = std::path::PathBuf::from(crate::library::absolute_path(path.trim()));
-    if file.is_dir() {
+    if crate::file_access::is_dir(&file) {
         file.push(MANIFEST_FILE);
     }
     let text = read_file(&file, figcraft_plugin::manifest::MAX_MANIFEST_BYTES)?;
@@ -295,10 +294,22 @@ pub(crate) fn module_of(s: &Session, p: &InstalledPlugin) -> Result<Arc<Vec<u8>>
     let Some(path) = &p.path else {
         return Err(EngineError::Other(format!("{} was imported without a manifest file: import it again", p.manifest.name)));
     };
-    #[cfg(not(target_arch = "wasm32"))]
-    return module_file(std::path::Path::new(path), &p.manifest).map(Arc::new);
-    #[cfg(target_arch = "wasm32")]
-    return Err(EngineError::Other(format!("{path}: there are no files in the browser")));
+    module_from_disk(s, p, path)
+}
+
+#[cfg(not(target_arch = "wasm32"))]
+fn module_from_disk(s: &Session, p: &InstalledPlugin, path: &str) -> Result<Arc<Vec<u8>>> {
+    let file = std::path::Path::new(path);
+    let read = || module_file(file, &p.manifest).map(Arc::new);
+    // A plugin installed from a directory lives in the app's own install folder, not among the
+    // files automation roots confine.
+    let own = p.source.is_some() && s.plugins.install_dir.as_deref().is_some_and(|d| crate::file_access::within_app_folder(file, d));
+    if own { crate::file_access::app_owned(read) } else { read() }
+}
+
+#[cfg(target_arch = "wasm32")]
+fn module_from_disk(_: &Session, _: &InstalledPlugin, path: &str) -> Result<Arc<Vec<u8>>> {
+    Err(EngineError::Other(format!("{path}: there are no files in the browser")))
 }
 
 /// The sandbox limits for a run, with `fuel` lowering the instruction budget.

crates/engine/src/rest_slot_tests.rs

@@ -0,0 +1,91 @@
+//! Slots opened from REST file JSON: instances keep their own slot content through edits and
+//! moves of the mains, and through saving.
+
+use crate::Session;
+use crate::components::tests::{ex, healthy, idv};
+use crate::components::*;
+use base64::Engine as _;
+use figcraft_doc::*;
+use serde_json::{Value, json};
+
+fn at(x: f64, y: f64) -> Value {
+    json!([[1, 0, x], [0, 1, y]])
+}
+
+fn text(id: &str, s: &str) -> Value {
+    json!({"id": id, "name": s, "type": "TEXT", "characters": s, "relativeTransform": at(0.0, 0.0), "size": {"x": 100, "y": 20}})
+}
+
+/// A Chip main, a Container main with an empty "Slot", and an instance of Container whose slot
+/// holds a text and a chip.
+fn file() -> Value {
+    let slot = |id: &str, kids: Value| json!({"id": id, "name": "Slot", "type": "SLOT", "relativeTransform": at(10.0, 40.0), "size": {"x": 280, "y": 100}, "children": kids});
+    let guid = |l: u32| json!({"guid": {"sessionID": 5, "localID": l}});
+    let chip = json!({"id": "2:3", "name": "Chip", "type": "INSTANCE", "componentId": "1:9", "relativeTransform": at(0.0, 30.0), "size": {"x": 40, "y": 20},
+        "children": [{"id": "I2:3;1:10", "name": "Dot", "type": "ELLIPSE", "relativeTransform": at(2.0, 2.0), "size": {"x": 16, "y": 16}}]});
+    json!({"name": "Slots", "document": {"id": "0:0", "type": "DOCUMENT", "children": [{"id": "0:1", "name": "Page", "type": "CANVAS", "children": [
+        {"id": "1:9", "name": "Chip", "type": "COMPONENT", "relativeTransform": at(0.0, 400.0), "size": {"x": 40, "y": 20}, "children": [
+            {"id": "1:10", "name": "Dot", "type": "ELLIPSE", "relativeTransform": at(2.0, 2.0), "size": {"x": 16, "y": 16}}
+        ]},
+        {"id": "1:2", "name": "Container", "type": "COMPONENT", "relativeTransform": at(0.0, 0.0), "size": {"x": 300, "y": 160},
+         "componentPropertyDefinitions": {"Slot#1:3": {"type": "SLOT", "defaultValue": guid(1)}},
+         "children": [text("1:4", "Title"), slot("1:5", json!([]))]},
+        {"id": "2:1", "name": "Container", "type": "INSTANCE", "componentId": "1:2", "relativeTransform": at(400.0, 0.0), "size": {"x": 300, "y": 160},
+         "componentProperties": {"Slot#1:3": {"type": "SLOT", "value": guid(7)}},
+         "children": [text("I2:1;1:4", "Title"), slot("I2:1;1:5", json!([text("2:2", "Reports in progress"), chip]))]}
+    ]}]}})
+}
+
+fn named(doc: &Document, kind: fn(&NodeKind) -> bool, name: &str) -> NodeId {
+    doc.nodes().find(|n| n.name == name && kind(&n.kind)).map(|n| n.id).unwrap_or_else(|| panic!("no {name}"))
+}
+
+/// The instance's slot and the names of what it holds.
+fn slot_content(s: &Session) -> (NodeId, Vec<String>) {
+    let doc = s.doc().unwrap();
+    let inst = named(doc, |k| matches!(k, NodeKind::Instance { .. }), "Container");
+    let (slot, _) = slots_of(doc, inst).into_iter().next().expect("the instance has its slot");
+    let names = doc.node(slot).unwrap().children.iter().map(|c| doc.node(*c).unwrap().name.clone()).collect();
+    (slot, names)
+}
+
+#[test]
+fn rest_slot_content_survives_main_edits_moves_and_saving() {
+    let mut s = Session::new();
+    let data = base64::engine::general_purpose::STANDARD.encode(serde_json::to_vec(&file()).unwrap());
+    ex(&mut s, "file.open", json!({"data": data, "name": "slots.json"}));
+    healthy(&s);
+    let want = vec!["Reports in progress".to_string(), "Chip".to_string()];
+    let (slot, names) = slot_content(&s);
+    assert_eq!(names, want);
+    let doc = s.doc().unwrap();
+    assert_eq!(slot_name(doc, slot).as_deref(), Some("Slot"));
+    assert!(slot_edited(doc, slot), "the instance's own content");
+    let chip = named(doc, |k| matches!(k, NodeKind::Instance { .. }), "Chip");
+    assert!(!inside_instance(doc, chip), "content stands alone");
+
+    // Edit and move both mains (the container's and the one used in the content).
+    let main = named(doc, |k| matches!(k, NodeKind::Component { .. }), "Container");
+    let chip_main = named(doc, |k| matches!(k, NodeKind::Component { .. }), "Chip");
+    let title = doc.node(main).unwrap().children[0];
+    ex(&mut s, "node.set", json!({"id": title, "props": {"fill": "#ff0000"}}));
+    ex(&mut s, "node.set", json!({"id": main, "props": {"width": 320}}));
+    let holder = idv(&ex(&mut s, "frame.create", json!({"x": -1000, "y": 0, "width": 900, "height": 900, "name": "Design system"})));
+    ex(&mut s, "node.reparent", json!({"ids": [main, chip_main], "parent": holder}));
+    healthy(&s);
+    assert_eq!(slot_content(&s).1, want, "kept across syncs");
+
+    // Saving and opening again keeps it.
+    let bytes = figcraft_format::save_bytes(s.doc().unwrap(), None).unwrap();
+    let data = base64::engine::general_purpose::STANDARD.encode(bytes);
+    let mut again = Session::new();
+    ex(&mut again, "file.open", json!({"data": data, "name": "slots.figcraft"}));
+    healthy(&again);
+    let (slot, names) = slot_content(&again);
+    assert_eq!(names, want);
+    assert!(slot_edited(again.doc().unwrap(), slot));
+
+    // Resetting the slot shows the main's (empty) default content.
+    ex(&mut again, "instance.resetSlot", json!({"id": slot}));
+    assert!(slot_content(&again).1.is_empty());
+}

crates/engine/src/selection_colors.rs

@@ -0,0 +1,245 @@
+//! Paints used by the selection, including descendants and effective text-range fills.
+//! Targets name paint slots rather than colors: a live edit must not capture other slots when
+//! its color happens to become equal to another selection color.
+
+use std::collections::{BTreeMap, BTreeSet};
+
+use figcraft_color::{Paint, PaintKind};
+use figcraft_doc::{Document, NodeId, NodeKind, StyleKind};
+use serde::{Deserialize, Serialize};
+use serde_json::{Value, json};
+
+use crate::cmd::lists::{BoundList, list_binding};
+use crate::params::*;
+use crate::{CommandSpec, Result, Session, bad, spec};
+
+#[derive(Clone, Debug, PartialEq, Eq, Hash, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase", deny_unknown_fields)]
+pub struct PaintTarget {
+    pub id: NodeId,
+    pub fills: bool,
+    pub index: usize,
+    /// Character offsets, not byte offsets. None means the node's fill or stroke list.
+    pub range: Option<(usize, usize)>,
+}
+
+impl PaintTarget {
+    pub fn paints(&self, doc: &Document) -> Option<Vec<Paint>> {
+        let n = doc.node(self.id)?;
+        if let Some((start, end)) = self.range {
+            let t = n.kind.text()?;
+            if !self.fills || start > end || end > t.char_count() || (start == end && end != 0) {
+                return None;
+            }
+            Some(t.style_at(start).fills.clone().unwrap_or_else(|| n.fills.clone()))
+        } else {
+            Some(if self.fills { n.fills.clone() } else { n.strokes.clone() })
+        }
+    }
+
+    pub fn paint(&self, doc: &Document) -> Option<Paint> {
+        self.paints(doc)?.get(self.index).cloned()
+    }
+}
+
+#[derive(Clone, Debug, Serialize)]
+pub struct SelectionColor {
+    pub paint: Paint,
+    pub style: Option<String>,
+    pub variable: Option<String>,
+    pub targets: Vec<PaintTarget>,
+}
+
+/// Deterministic order, one target per slot even when a parent and child are both selected.
+/// Images and patterns are assets rather than selection colors. Hidden paints are omitted.
+pub fn collect(doc: &Document, ids: &[NodeId]) -> Vec<SelectionColor> {
+    let mut groups: Vec<SelectionColor> = Vec::new();
+    let mut seen = BTreeSet::new();
+    let mut by_paint: BTreeMap<(Option<String>, Option<String>, String), usize> = BTreeMap::new();
+    let mut pending: Vec<_> = ids.iter().rev().copied().collect();
+    while let Some(id) = pending.pop() {
+        if !seen.insert(id) {
+            continue;
+        }
+        let Some(n) = doc.node(id) else { continue };
+        if n.is_mask {
+            continue;
+        }
+        if !matches!(n.kind, NodeKind::BooleanOp { .. }) {
+            pending.extend(n.children.iter().rev().copied());
+        }
+        let mut add = |paints: &[Paint], fills: bool, range: Option<(usize, usize)>| {
+            for (index, paint) in paints.iter().enumerate() {
+                if !paint.visible || !matches!(paint.kind, PaintKind::Solid { .. } | PaintKind::Gradient(_)) {
+                    continue;
+                }
+                let target = PaintTarget { id, fills, index, range };
+                let inherited = range.is_none_or(|(start, _)| n.kind.text().is_some_and(|t| t.style_at(start).fills.is_none()));
+                let style = inherited.then(|| if fills { n.styles.fill.clone() } else { n.styles.stroke.clone() }).flatten();
+                let list = if fills { BoundList::Fills } else { BoundList::Strokes };
+                let variable = inherited
+                    .then(|| {
+                        n.bound.iter().find_map(|(key, var)| {
+                            list_binding(key).filter(|(l, i, field)| *l == list && *i == index && *field == "color").map(|_| var.clone())
+                        })
+                    })
+                    .flatten();
+                let Ok(value) = serde_json::to_string(paint) else { continue };
+                let key = (style.clone(), variable.clone(), value);
+                if let Some(index) = by_paint.get(&key).copied() {
+                    if let Some(g) = groups.get_mut(index) {
+                        g.targets.push(target);
+                    }
+                } else {
+                    by_paint.insert(key, groups.len());
+                    groups.push(SelectionColor { paint: paint.clone(), style, variable, targets: vec![target] });
+                }
+            }
+        };
+        if let NodeKind::Text(t) = &n.kind {
+            let spans = t.spans();
+            if spans.iter().all(|(_, _, style)| style.fills.is_none()) {
+                add(&n.fills, true, None);
+            } else {
+                for (start, end, style) in spans {
+                    add(style.fills.as_deref().unwrap_or(&n.fills), true, Some((start, end)));
+                }
+            }
+        } else {
+            add(&n.fills, true, None);
+        }
+        add(&n.strokes, false, None);
+    }
+    groups
+}
+
+pub fn specs() -> Vec<CommandSpec> {
+    vec![
+        spec!(
+            "selection.colors",
+            "Selection colors",
+            "{ids?} → {colors: [{paint, targets}]}; includes descendants and text ranges",
+            false,
+            |s, p| { Ok(json!({"colors": collect(s.doc()?, &targets(s, p))})) }
+        ),
+        spec!("selection.setPaint", "Change selection color", "{targets: [{id, fills, index, range: [start,end] | null}], paint}", true, set_paint),
+        spec!(
+            "selection.applyColorStyle",
+            "Apply selection color style",
+            "{targets, style}; applies the color style to matching fill/stroke lists (text ranges keep typography)",
+            true,
+            apply_style
+        ),
+        spec!(
+            "selection.selectColor",
+            "Select layers with color",
+            "{targets} → {ids}; selects the layers owning these paint slots",
+            false,
+            select_color
+        ),
+    ]
+}
+
+fn checked_targets(s: &Session, p: &Value, cmd: &str) -> Result<Vec<PaintTarget>> {
+    let ts: Vec<PaintTarget> = parse(cmd, p, "targets")?.ok_or_else(|| bad(cmd, "`targets` is required"))?;
+    if ts.is_empty() {
+        return Err(bad(cmd, "`targets` must not be empty"));
+    }
+    for t in &ts {
+        if t.paint(s.doc()?).is_none() {
+            return Err(bad(cmd, "a selection color target no longer exists"));
+        }
+    }
+    Ok(ts)
+}
+
+/// Detach variables only where the explicit edit changed their value. In particular, an
+/// opacity edit keeps the color binding and a range edit keeps other characters' node bindings.
+fn unbind_changed(n: &mut figcraft_doc::Node, t: &PaintTarget, old: &Paint, new: &Paint) {
+    // Range fills override the node's paints; the node binding still belongs to other chars.
+    if t.range.is_some() {
+        return;
+    }
+    let list = if t.fills { BoundList::Fills } else { BoundList::Strokes };
+    n.bound.retain(|key, _| {
+        let Some((l, index, field)) = list_binding(key) else { return true };
+        if l != list || index != t.index {
+            return true;
+        }
+        match field {
+            "color" => match (&old.kind, &new.kind) {
+                (PaintKind::Solid { color: a }, PaintKind::Solid { color: b }) => a == b,
+                _ => false,
+            },
+            "opacity" => old.opacity == new.opacity,
+            _ => {
+                let stop = field.strip_prefix("stops/").and_then(|s| s.strip_suffix("/color")).and_then(|s| s.parse::<usize>().ok());
+                match (stop, &old.kind, &new.kind) {
+                    (Some(i), PaintKind::Gradient(a), PaintKind::Gradient(b)) => a.stops.get(i).map(|s| s.color) == b.stops.get(i).map(|s| s.color),
+                    (Some(_), _, _) => false,
+                    _ => old == new,
+                }
+            }
+        }
+    });
+}
+
+fn set_paint(s: &mut Session, p: &Value) -> Result<Value> {
+    const CMD: &str = "selection.setPaint";
+    let targets = checked_targets(s, p, CMD)?;
+    let paint = get(p, "paint").and_then(paint_of).ok_or_else(|| bad(CMD, "`paint` must be a paint"))?;
+    for target in &targets {
+        let mut paints = target.paints(s.doc()?).ok_or_else(|| bad(CMD, "invalid target"))?;
+        let Some(slot) = paints.get_mut(target.index) else { return Err(bad(CMD, "invalid paint index")) };
+        if *slot == paint {
+            continue;
+        }
+        let old = slot.clone();
+        *slot = paint.clone();
+        let n = s.doc_mut()?.get_mut(target.id)?;
+        unbind_changed(n, target, &old, &paint);
+        if let Some((start, end)) = target.range {
+            if let NodeKind::Text(t) = &mut n.kind {
+                t.restyle(start, end, |style| style.fills = Some(paints.clone()));
+            }
+        } else if target.fills {
+            n.fills = paints;
+            n.styles.fill = None;
+        } else {
+            n.strokes = paints;
+            n.styles.stroke = None;
+        }
+    }
+    Ok(json!({"ok": true}))
+}
+
+fn apply_style(s: &mut Session, p: &Value) -> Result<Value> {
+    const CMD: &str = "selection.applyColorStyle";
+    let targets = checked_targets(s, p, CMD)?;
+    let name = req_string(CMD, p, "style")?;
+    let style = s.doc()?.style(&name).cloned().ok_or_else(|| bad(CMD, "no such color style"))?;
+    if !matches!(style.kind, StyleKind::Paint { .. }) {
+        return Err(bad(CMD, "a color style is required"));
+    }
+    for target in &targets {
+        if let Some((start, end)) = target.range {
+            // Text ranges have typography-style links, not paint-style links. Copy resolved paint
+            // values just as an explicit range fill does; never replace its font or size.
+            let StyleKind::Paint { paints } = crate::style_vars::kind_for(s.doc()?, &style, target.id).into_owned() else { continue };
+            let n = s.doc_mut()?.get_mut(target.id)?;
+            if let NodeKind::Text(t) = &mut n.kind {
+                t.restyle(start, end, |st| st.fills = Some(paints.clone()));
+            }
+        } else {
+            crate::cmd::styles::apply_style_ref(s.doc_mut()?, target.id, if target.fills { "fillStyle" } else { "strokeStyle" }, Some(&style.id))?;
+        }
+    }
+    Ok(json!({"ok": true}))
+}
+
+fn select_color(s: &mut Session, p: &Value) -> Result<Value> {
+    let ts = checked_targets(s, p, "selection.selectColor")?;
+    let ids: Vec<_> = ts.iter().map(|t| t.id).collect::<BTreeSet<_>>().into_iter().collect();
+    crate::cmd::edit::select_and_page(s, ids.clone())?;
+    Ok(json!({"ids": ids}))
+}

crates/engine/src/selection_spacing.rs

@@ -0,0 +1,132 @@
+//! Smart-selection spacing in page coordinates. Tracks contain aligned siblings (columns for
+//! horizontal spacing, rows for vertical spacing); moving a track preserves its internal layout.
+use figcraft_doc::{Document, NodeId, NodeKind};
+use figcraft_geom::Rect;
+
+const EPS: f64 = 0.01;
+
+#[derive(Clone, Debug)]
+pub struct Track {
+    pub ids: Vec<NodeId>,
+    pub bounds: Rect,
+    anchor: Rect,
+}
+
+#[derive(Clone, Debug)]
+pub struct Axis {
+    pub tracks: Vec<Track>,
+    pub vertical: bool,
+    /// None means the existing distances are mixed; setting a value makes them uniform.
+    pub value: Option<f64>,
+}
+
+impl Axis {
+    pub fn start(&self, b: Rect) -> f64 {
+        if self.vertical { b.y0 } else { b.x0 }
+    }
+    pub fn end(&self, b: Rect) -> f64 {
+        if self.vertical { b.y1 } else { b.x1 }
+    }
+    pub fn gap(&self, a: &Track, b: &Track) -> f64 {
+        self.start(b.bounds) - self.end(a.bounds)
+    }
+    /// Desired page-space translations, keeping the first track fixed.
+    pub fn offsets(&self, value: f64) -> Vec<(NodeId, f64)> {
+        let mut pos = self.tracks.first().map_or(0.0, |t| self.start(t.bounds));
+        let mut out = Vec::new();
+        for t in &self.tracks {
+            let delta = pos - self.start(t.bounds);
+            out.extend(t.ids.iter().map(|id| (*id, delta)));
+            pos += self.end(t.bounds) - self.start(t.bounds) + value;
+        }
+        out
+    }
+}
+
+#[derive(Clone, Debug, Default)]
+pub struct SelectionSpacing {
+    pub horizontal: Option<Axis>,
+    pub vertical: Option<Axis>,
+}
+
+/// Available only for movable, visible siblings outside normal auto-layout flow. Parent/child
+/// selections, instance internals and locked layers must not be moved indirectly by a gap edit.
+pub fn selection_spacing(doc: &Document, ids: &[NodeId]) -> SelectionSpacing {
+    let Some(first) = ids.first().and_then(|id| doc.node(*id)) else { return SelectionSpacing::default() };
+    if ids.len() < 2 || ids.len() > 2000 {
+        return SelectionSpacing::default();
+    }
+    let mut items = Vec::new();
+    for id in ids {
+        let Some(n) = doc.node(*id) else { return SelectionSpacing::default() };
+        if n.parent != first.parent
+            || !n.visible
+            || doc.ancestors(*id).into_iter().any(|a| doc.node(a).is_some_and(|n| !n.visible))
+            || crate::tools::locked_in(doc, *id)
+            || crate::components::inside_instance(doc, *id)
+            || matches!(n.kind, NodeKind::Page { .. })
+            || n.parent.and_then(|p| doc.node(p)).is_some_and(|p| p.layout.is_some() && !n.child_layout.absolute)
+        {
+            return SelectionSpacing::default();
+        }
+        let determinant = n.parent.map(|p| doc.world_transform(p).determinant()).unwrap_or(1.0);
+        if !determinant.is_finite() || determinant.abs() < 1e-12 {
+            return SelectionSpacing::default();
+        }
+        let Some(b) = doc.world_bounds(*id) else { return SelectionSpacing::default() };
+        if ![b.x0, b.y0, b.x1, b.y1].into_iter().all(f64::is_finite) || b.width() <= EPS || b.height() <= EPS {
+            return SelectionSpacing::default();
+        }
+        if !items.iter().any(|(i, _)| i == id) {
+            items.push((*id, b));
+        }
+    }
+    SelectionSpacing { horizontal: axis(&items, false), vertical: axis(&items, true) }
+}
+
+fn axis(items: &[(NodeId, Rect)], vertical: bool) -> Option<Axis> {
+    let edges = |b: Rect| if vertical { (b.y0, b.y1) } else { (b.x0, b.x1) };
+    let mut items = items.to_vec();
+    items.sort_by(|a, b| edges(a.1).0.total_cmp(&edges(b.1).0).then(a.0.cmp(&b.0)));
+    let mut tracks: Vec<Track> = Vec::new();
+    for (id, b) in items {
+        let (lo, hi) = edges(b);
+        let aligned = tracks.iter_mut().find(|t| {
+            let (a, z) = edges(t.anchor);
+            (lo - a).abs() <= EPS || (hi - z).abs() <= EPS || ((lo + hi - a - z) * 0.5).abs() <= EPS
+        });
+        if let Some(t) = aligned {
+            t.ids.push(id);
+            t.bounds = t.bounds.union(b);
+        } else {
+            tracks.push(Track { ids: vec![id], bounds: b, anchor: b });
+        }
+    }
+    if tracks.len() < 2 {
+        return None;
+    }
+    tracks.sort_by(|a, b| edges(a.bounds).0.total_cmp(&edges(b.bounds).0));
+    // Diagonally scattered layers aren't a row/column/grid selection.
+    let cross = |b: Rect| if vertical { (b.x0, b.x1) } else { (b.y0, b.y1) };
+    let low = tracks.iter().map(|t| cross(t.bounds).0).fold(f64::NEG_INFINITY, f64::max);
+    let high = tracks.iter().map(|t| cross(t.bounds).1).fold(f64::INFINITY, f64::min);
+    if high - low <= EPS {
+        return None;
+    }
+    let mut result = Axis { tracks, vertical, value: None };
+    let gaps: Vec<f64> = result.tracks.windows(2).filter_map(|p| p.first().zip(p.get(1)).map(|(a, b)| result.gap(a, b))).collect();
+    result.value = gaps.first().copied().filter(|v| gaps.iter().all(|g| (g - v).abs() <= EPS));
+    Some(result)
+}
+
+/// A spacing gesture never changes selection. Roll it back in its owning document, preserving
+/// a subsequent tab/page/selection change and leaving another document's gesture alone.
+pub fn cancel_gesture(session: &mut crate::Session, uid: u64) {
+    if let Some(ds) = session.docs.iter_mut().find(|d| d.uid == uid)
+        && let Some(it) = ds.interaction.take()
+    {
+        ds.doc = it.doc;
+        ds.revision += 1;
+        ds.clean_selection();
+    }
+}

crates/engine/src/selection_spacing_tests.rs

@@ -0,0 +1,123 @@
+use crate::{Session, selection_spacing::selection_spacing};
+use figcraft_doc::NodeId;
+use serde_json::json;
+
+fn rect(s: &mut Session, x: f64, y: f64, w: f64, h: f64, parent: Option<NodeId>) -> NodeId {
+    NodeId(s.execute("shape.rectangle", &json!({"x":x,"y":y,"width":w,"height":h,"parent":parent})).unwrap()["id"].as_u64().unwrap())
+}
+fn xy(s: &Session, id: NodeId) -> (f64, f64) {
+    let b = s.doc().unwrap().world_bounds(id).unwrap();
+    (b.x0, b.y0)
+}
+
+#[test]
+fn rows_columns_and_grids_keep_track_contents_and_sizes() {
+    let mut s = Session::new();
+    // Unequal widths, left-aligned columns. The column widths are 50 and 80; gaps 30 and 20.
+    let a = rect(&mut s, 100., 100., 50., 40., None);
+    let b = rect(&mut s, 180., 100., 80., 40., None);
+    let c = rect(&mut s, 100., 160., 30., 60., None);
+    let d = rect(&mut s, 180., 160., 40., 60., None);
+    let ids = [a, b, c, d];
+    let layout = selection_spacing(s.doc().unwrap(), &ids);
+    assert_eq!(layout.horizontal.unwrap().value, Some(30.));
+    assert_eq!(layout.vertical.unwrap().value, Some(20.));
+    s.execute("arrange.spacing", &json!({"ids":ids,"horizontal":12,"vertical":25})).unwrap();
+    assert_eq!(xy(&s, a), (100., 100.));
+    assert_eq!(xy(&s, b), (162., 100.));
+    assert_eq!(xy(&s, c), (100., 165.));
+    assert_eq!(xy(&s, d), (162., 165.));
+
+    assert_eq!(s.doc().unwrap().node(d).unwrap().width, 40.);
+    s.undo().unwrap();
+    assert_eq!(xy(&s, d), (180., 160.));
+    s.redo().unwrap();
+    assert_eq!(xy(&s, d), (162., 165.));
+    s.begin_interaction("Spacing").unwrap();
+    s.execute("arrange.spacing", &json!({"ids":ids,"horizontal":22,"fromGesture":true})).unwrap();
+    s.execute("arrange.spacing", &json!({"ids":ids,"vertical":35,"fromGesture":true})).unwrap();
+    assert_eq!(xy(&s, d), (172., 175.), "the unrequested axis keeps the earlier edit");
+    s.commit_interaction().unwrap();
+}
+
+#[test]
+fn mixed_gaps_normalize_and_fractional_negative_gaps_are_supported() {
+    let mut s = Session::new();
+    let a = rect(&mut s, 0., 0., 50., 40., None);
+    let b = rect(&mut s, 70., 0., 50., 40., None);
+    let c = rect(&mut s, 160., 0., 50., 40., None);
+    assert_eq!(selection_spacing(s.doc().unwrap(), &[a, b, c]).horizontal.unwrap().value, None);
+    s.execute("arrange.spacing", &json!({"ids":[a,b,c],"horizontal":-5.5})).unwrap();
+    assert_eq!(xy(&s, b), (44.5, 0.));
+    assert_eq!(xy(&s, c), (89., 0.));
+    assert_eq!(selection_spacing(s.doc().unwrap(), &[a, b, c]).horizontal.unwrap().value, Some(-5.5));
+}
+
+#[test]
+fn a_scrub_uses_the_original_tracks_after_crossing_and_makes_one_undo_step() {
+    let mut s = Session::new();
+    let a = rect(&mut s, 0., 0., 50., 40., None);
+    let b = rect(&mut s, 70., 0., 50., 40., None);
+    let c = rect(&mut s, 140., 0., 50., 40., None);
+    let before = s.undo_depth().0;
+    s.begin_interaction("Spacing").unwrap();
+    for v in [-100., 0., 30.] {
+        s.execute("arrange.spacing", &json!({"ids":[a,b,c],"horizontal":v,"fromGesture":true})).unwrap();
+    }
+    assert_eq!(xy(&s, b), (80., 0.));
+    assert_eq!(xy(&s, c), (160., 0.));
+    s.commit_interaction().unwrap();
+    assert_eq!(s.undo_depth().0, before + 1);
+    s.undo().unwrap();
+    assert_eq!(xy(&s, c), (140., 0.));
+}
+
+#[test]
+fn unsafe_selections_and_invalid_axes_are_rejected_without_changes() {
+    let mut s = Session::new();
+    let a = rect(&mut s, 0., 0., 50., 40., None);
+    let b = rect(&mut s, 70., 0., 50., 40., None);
+    for props in [json!({"locked":true}), json!({"visible":false})] {
+        s.execute("node.set", &json!({"id":b,"props":props})).unwrap();
+        assert!(s.execute("arrange.spacing", &json!({"ids":[a,b],"horizontal":5})).is_err());
+        s.execute("node.set", &json!({"id":b,"props":{"locked":false,"visible":true}})).unwrap();
+    }
+    for args in [
+        json!({"ids":[a,b],"vertical":5}),
+        json!({"ids":[a,b],"horizontal":5,"vertical":5}),
+        json!({"ids":[a,b],"horizontal":"bad"}),
+        json!({"ids":[a,b],"horizontal":1e300}),
+    ] {
+        assert!(s.execute("arrange.spacing", &args).is_err());
+        assert_eq!(xy(&s, b), (70., 0.));
+    }
+    let f = NodeId(
+        s.execute("frame.create", &json!({"x":0,"y":0,"width":300,"height":100,"props":{"layout":"horizontal"}})).unwrap()["id"].as_u64().unwrap(),
+    );
+    let x = rect(&mut s, 0., 0., 50., 40., Some(f));
+    let y = rect(&mut s, 70., 0., 50., 40., Some(f));
+    assert!(selection_spacing(s.doc().unwrap(), &[x, y]).horizontal.is_none());
+    assert!(selection_spacing(s.doc().unwrap(), &[a, x]).horizontal.is_none());
+}
+
+#[test]
+fn rotated_parents_use_page_space_and_cancellation_stays_with_its_document() {
+    let mut s = Session::new();
+    let f = NodeId(
+        s.execute("frame.create", &json!({"x":100,"y":100,"width":300,"height":200,"props":{"rotation":90}})).unwrap()["id"].as_u64().unwrap(),
+    );
+    let a = rect(&mut s, 0., 0., 50., 40., Some(f));
+    let b = rect(&mut s, 70., 0., 50., 40., Some(f));
+    let before = xy(&s, b);
+    let uid = s.ds().unwrap().uid;
+    s.begin_interaction("Spacing").unwrap();
+    s.execute("arrange.spacing", &json!({"ids":[a,b],"vertical":40,"fromGesture":true})).unwrap();
+    assert!(((xy(&s, b).1 - xy(&s, a).1).abs() - 90.0).abs() < 1e-7, "50-high rotated rectangles must have a 40-point gap");
+    s.execute("file.new", &json!({})).unwrap();
+    s.begin_interaction("Unrelated").unwrap();
+    crate::selection_spacing::cancel_gesture(&mut s, uid);
+    assert!(s.ds().unwrap().interaction.is_some());
+    s.active = 0;
+    assert_eq!(xy(&s, b), before);
+    assert!(s.ds().unwrap().interaction.is_none());
+}

crates/engine/src/tests.rs

@@ -415,6 +415,9 @@ fn every_command_survives_junk_params() {
         // Online files: ids, servers, refreshes, actions and names as junk.
         json!({"file": [1], "server": 7, "refresh": "maybe", "action": "share", "name": {"x": 1}}),
         json!({"file": "../x", "server": "wss://\u{0}", "refresh": true, "action": "unshare", "name": 5}),
+        // Selection color slots: malformed indexes, ranges and paints.
+        json!({"targets": [{"id": 2, "fills": true, "index": -1, "range": [0, 1e308]}], "paint": {"type": "solid", "color": "invalid"}}),
+        json!({"targets": [{"id": 2, "fills": "yes", "index": 0, "range": [4, 1]}], "style": 5}),
         // Rotation origins and placing with a tool as junk.
         json!({"tool": [1], "x": 1e308, "y": "NaN", "reset": "maybe", "on": {"x": 1}}),
         json!({"tool": "frame", "x": -1e308, "y": 1e308, "reset": true, "on": "yes"}),

crates/engine/src/tools.rs

@@ -661,6 +661,9 @@ fn on_corner_square(doc: &Document, sel: &[NodeId], p: Point, zoom: f64) -> bool
 /// handles: the canvas draws just its outline (the handles still answer just outside it).
 pub const SMALL_BOX_PX: f64 = 16.0;
 
+/// The stroke the Pencil draws: its colour and weight (the canvas previews it the same).
+pub const PENCIL_STROKE: (figcraft_color::Color, f64) = (figcraft_color::Color::BLACK, 2.0);
+
 /// The shorter and longer sides, in screen pixels, of the box with `corners` (tl, tr, br, bl).
 pub fn box_sides_px(corners: &[Point; 4], zoom: f64) -> (f64, f64) {
     let [a, b, _, d] = corners;
@@ -1859,6 +1862,20 @@ impl Session {
         if self.tool.tool == ToolId::Pen {
             return self.pen_finish();
         }
+        // A frame's or section's name label: rename it there (the canvas puts a field over it).
+        // Labels come before widgets, as on a press; the second press began a move: undo it.
+        if matches!(self.tool.tool, ToolId::Move | ToolId::Scale)
+            && !(ev.shift || ev.cmd || ev.alt)
+            && let Some(id) = label_at(&doc, page, &self.tool.labels, ev.p())
+        {
+            self.tool.gesture = Gesture::None;
+            self.cancel_interaction()?;
+            if sel != [id] {
+                self.set_selection(vec![id]);
+            }
+            self.request_ui("canvas.renameLabel", serde_json::json!({"id": id}));
+            return Ok(());
+        }
         // Quick clicks on a widget's clickable part are clicks, one by one.
         if matches!(self.tool.tool, ToolId::Move | ToolId::Scale)
             && !(ev.shift || ev.cmd || ev.alt)
@@ -2051,13 +2068,7 @@ impl Session {
         if self.tool.pen.is_none()
             && let Some((id, v)) = selected_end_at(&doc, &self.selection(), ev.p(), 8.0 / ev.zoom.max(1e-6))
         {
-            self.set_tool(ToolId::Move);
-            crate::vectoredit::begin(self, id)?;
-            crate::vectoredit::set_tool(self, crate::vectoredit::VTool::Pen)?;
-            return crate::vectoredit::set_state(self, |e| {
-                e.anchor = Some(v);
-                e.vertices = vec![v];
-            });
+            return self.pen_edit(id, Some(v));
         }
         let pen = self.tool.pen.get_or_insert_with(PenPath::default);
         // Clicking the first anchor closes the path.
@@ -2175,7 +2186,30 @@ impl Session {
         Ok(())
     }
 
-    /// Finish the pen path (Enter/Escape/double-click).
+    /// Edit `id` as a vector with the pen, going on from point `anchor` (or, without one, starting
+    /// a new path in the same layer at the next click).
+    fn pen_edit(&mut self, id: NodeId, anchor: Option<usize>) -> Result<()> {
+        self.set_tool(ToolId::Move);
+        crate::vectoredit::begin(self, id)?;
+        crate::vectoredit::set_tool(self, crate::vectoredit::VTool::Pen)?;
+        crate::vectoredit::set_state(self, |e| {
+            e.anchor = anchor;
+            e.vertices = anchor.into_iter().collect();
+        })
+    }
+
+    /// Enter/Escape while the pen draws: the path ends but its layer stays in edit mode with the
+    /// pen, so the next path joins the same vector (another Escape leaves edit mode).
+    pub fn pen_end(&mut self) -> Result<()> {
+        let id = self.tool.pen.as_ref().and_then(|p| p.id);
+        self.pen_finish()?;
+        match id {
+            Some(id) if self.doc()?.contains(id) => self.pen_edit(id, None),
+            _ => Ok(()),
+        }
+    }
+
+    /// Finish the pen path (and keep the pen tool: double-click, Delete, a tool switch).
     pub fn pen_finish(&mut self) -> Result<()> {
         let pen = self.tool.pen.take();
         self.tool.overlay.pen.clear();
@@ -2210,8 +2244,8 @@ impl Session {
         let mut local = fitted.clone();
         local.apply_affine(pw.inverse());
         let _ = d;
-        let mut props =
-            json!({"fills": [], "strokes": ["#000000"], "strokeWeight": 2, "strokeCap": "round", "strokeJoin": "round", "strokeAlign": "center"});
+        let (color, weight) = PENCIL_STROKE;
+        let mut props = json!({"fills": [], "strokes": [color.to_css_hex()], "strokeWeight": weight, "strokeCap": "round", "strokeJoin": "round", "strokeAlign": "center"});
         // Pen pressure becomes the stroke's width profile (brushes follow it too).
         if let Some(points) = pressure_profile(points, pressure) {
             props["widthProfile"] = json!(points);
@@ -2320,7 +2354,7 @@ impl Session {
             return Ok(());
         }
         if self.tool.pen.is_some() {
-            return self.pen_finish();
+            return self.pen_end();
         }
         if self.tool.busy() {
             self.tool.gesture = Gesture::None;

crates/engine/src/variables_import_shapes_tests.rs

@@ -0,0 +1,60 @@
+//! `variable.import` reads `variables` next to `variableCollections`, under `meta` or at the top
+//! level, and never imports nothing without saying so (#790).
+
+use serde_json::{Value, json};
+
+use crate::Session;
+
+fn collections() -> Value {
+    json!({"VC:1": {"id": "VC:1", "name": "Theme", "modes": [{"modeId": "1:0", "name": "Light"}], "defaultModeId": "1:0",
+                    "variableIds": ["VariableID:1"]}})
+}
+
+fn variables() -> Value {
+    json!({"VariableID:1": {"id": "VariableID:1", "name": "bg", "variableCollectionId": "VC:1", "resolvedType": "COLOR",
+                            "valuesByMode": {"1:0": {"r": 1.0, "g": 1.0, "b": 1.0, "a": 1.0}}}})
+}
+
+fn import(json: Value) -> Value {
+    let mut s = Session::new();
+    match s.execute("variable.import", &json!({"variables": json})) {
+        Ok(r) => r,
+        Err(e) => panic!("{e}"),
+    }
+}
+
+#[test]
+fn variables_import_reads_every_shape() {
+    for shape in [
+        json!({"meta": {"variableCollections": collections(), "variables": variables()}}),
+        json!({"variableCollections": collections(), "variables": variables()}),
+        json!({"meta": {"variableCollections": collections()}, "variables": variables()}),
+        json!({"variableCollections": collections(), "meta": {"variables": variables()}}),
+    ] {
+        let r = import(shape.clone());
+        assert_eq!((r["collections"].as_u64(), r["variables"].as_u64()), (Some(1), Some(1)), "{shape}: {r}");
+        assert_eq!(r["warnings"], json!([]), "{shape}: {r}");
+    }
+}
+
+#[test]
+fn variables_import_never_imports_nothing_silently() {
+    // Collections without variables: they are added, with a warning saying where variables go.
+    let r = import(json!({"meta": {"variableCollections": collections()}}));
+    assert_eq!((r["collections"].as_u64(), r["variables"].as_u64()), (Some(1), Some(0)), "{r}");
+    assert!(r["warnings"].to_string().contains("no variables found: expected `meta.variables`"), "{r}");
+    // An empty file's export reads back with the same warning, not an error.
+    let mut s = Session::new();
+    let text = s.execute("variable.export", &json!({})).unwrap()["text"].as_str().unwrap().to_string();
+    let r = s.execute("variable.import", &json!({"variables": text})).unwrap();
+    assert!(r["warnings"].to_string().contains("no variables found"), "{r}");
+    // Collections listing variables that aren't there.
+    let mut colls = collections();
+    colls["VC:1"]["variableIds"] = json!(["VariableID:1", "VariableID:2"]);
+    let r = import(json!({"meta": {"variableCollections": colls, "variables": variables()}}));
+    assert_eq!(r["variables"].as_u64(), Some(1), "{r}");
+    assert!(r["warnings"].to_string().contains("1 of the 2 variables the collections list in `variableIds` weren't imported"), "{r}");
+    // No collections anywhere: an error naming the expected shape.
+    let e = Session::new().execute("variable.import", &json!({"variables": {"variables": variables()}})).unwrap_err().to_string();
+    assert!(e.contains("(`meta.variableCollections` and `meta.variables`)"), "{e}");
+}

crates/engine/src/vector_behaviour_tests.rs

@@ -439,3 +439,61 @@ fn bend_paint_bucket_cut_join_and_eraser_tools() {
     assert_eq!(net(&s, id).segments.len(), 2, "the eraser removes what it passes over");
     assert_eq!(s.doc().unwrap().node(page).unwrap().children, vec![id], "and the pieces stay one layer");
 }
+
+#[test]
+fn vector_paths_take_the_requested_size_and_refuse_empty_geometry() {
+    let mut s = Session::new();
+    let path = "M0 0 L24 0 L24 24 L0 24 Z";
+    let intrinsic = id_of(&ex(&mut s, "vector.create", json!({"path": path}))["id"]).unwrap();
+    let n = s.doc().unwrap().node(intrinsic).unwrap();
+    assert_eq!((n.width, n.height), (24.0, 24.0), "a path without a size keeps its intrinsic box");
+    // Both sides: each scales independently, like resizing a vector.
+    let both = id_of(&ex(&mut s, "vector.create", json!({"path": path, "width": 16, "height": 8}))["id"]).unwrap();
+    let n = s.doc().unwrap().node(both).unwrap();
+    assert_eq!((n.width, n.height), (16.0, 8.0));
+    let n = net(&s, both);
+    let max = n.vertices.iter().fold((0.0f64, 0.0f64), |(x, y), v| (x.max(v.x), y.max(v.y)));
+    assert!((max.0 - 16.0).abs() < 1e-9 && (max.1 - 8.0).abs() < 1e-9, "{max:?}: the geometry itself is scaled");
+    // One side: the other keeps its proportion.
+    let width = id_of(&ex(&mut s, "vector.create", json!({"path": path, "width": 16}))["id"]).unwrap();
+    let n = s.doc().unwrap().node(width).unwrap();
+    assert_eq!((n.width, n.height), (16.0, 16.0));
+    // A path or point set that draws nothing is an error, not an invisible zero-size layer.
+    let e = s.execute("vector.create", &json!({"path": "M5 5"})).unwrap_err().to_string();
+    assert!(e.contains("draws nothing"), "{e}");
+    let e = s.execute("vector.create", &json!({"points": [[5, 5], [5, 5]]})).unwrap_err().to_string();
+    assert!(e.contains("draws nothing"), "{e}");
+    // A size on an axis the geometry has none of is refused, not silently ignored.
+    let e = s.execute("vector.create", &json!({"path": "M0 0 L0 24", "width": 16})).unwrap_err().to_string();
+    assert!(e.contains("horizontal extent"), "{e}");
+    let e = s.execute("vector.create", &json!({"path": "M0 0 L24 0", "height": 16})).unwrap_err().to_string();
+    assert!(e.contains("vertical extent"), "{e}");
+    // But 0 on an axis it has none of is what it already is: a horizontal line with height 0.
+    let line = id_of(&ex(&mut s, "vector.create", json!({"path": "M0 0 L24 0", "width": 16, "height": 0}))["id"]).unwrap();
+    let n = s.doc().unwrap().node(line).unwrap();
+    assert_eq!((n.width, n.height), (16.0, 0.0));
+    // A size of 0 or less on an axis it has would flatten it, so it is refused, alone or with the other.
+    for p in [json!({"path": path, "width": 0}), json!({"path": path, "width": 16, "height": 0}), json!({"path": path, "width": -4, "height": 8})] {
+        let e = s.execute("vector.create", &p).unwrap_err().to_string();
+        assert!(e.contains("positive"), "{p}: {e}");
+    }
+}
+
+#[test]
+fn vector_points_take_the_requested_size() {
+    let mut s = Session::new();
+    let points = json!([[10, 20], [34, 20], [34, 32]]);
+    let corners = |s: &Session, id: NodeId| net(s, id).vertices.iter().map(|v| (v.x, v.y)).collect::<Vec<_>>();
+    // Both sides: each axis scales on its own; the vertices move with the box.
+    let both = id_of(&ex(&mut s, "vector.create", json!({"points": points, "x": 10, "y": 20, "width": 48, "height": 6}))["id"]).unwrap();
+    let n = s.doc().unwrap().node(both).unwrap();
+    assert_eq!((n.width, n.height), (48.0, 6.0));
+    assert_eq!(corners(&s, both), vec![(0.0, 0.0), (48.0, 0.0), (48.0, 6.0)]);
+    // One side: the other keeps its proportion.
+    let one = id_of(&ex(&mut s, "vector.create", json!({"points": points, "height": 24}))["id"]).unwrap();
+    let n = s.doc().unwrap().node(one).unwrap();
+    assert_eq!((n.width, n.height), (48.0, 24.0));
+    assert_eq!(corners(&s, one), vec![(0.0, 0.0), (48.0, 0.0), (48.0, 24.0)]);
+    let e = s.execute("vector.create", &json!({"points": points, "width": 16, "height": -1})).unwrap_err().to_string();
+    assert!(e.contains("positive"), "{e}");
+}

crates/engine/src/vectoredit.rs

@@ -508,16 +508,15 @@ pub fn begin_many(s: &mut Session, ids: &[NodeId]) -> Result<()> {
     let before = s.ds()?.doc.clone();
     let mut edited = Vec::new();
     let mut first_err = None;
-    {
-        let doc = s.doc_mut()?;
-        for id in ids.iter().take(MAX_EDITED) {
-            if edited.contains(id) {
-                continue;
-            }
-            match ensure_vector(doc, *id) {
-                Ok(()) => edited.push(*id),
-                Err(e) => first_err = first_err.or(Some(e)),
-            }
+    for id in ids.iter().take(MAX_EDITED) {
+        if edited.contains(id) {
+            continue;
+        }
+        // Vectors are left untouched, so editing only them records no undo step.
+        let is_vector = before.node(*id).is_some_and(|n| matches!(n.kind, NodeKind::Vector { .. }));
+        match if is_vector { Ok(()) } else { ensure_vector(s.doc_mut()?, *id) } {
+            Ok(()) => edited.push(*id),
+            Err(e) => first_err = first_err.or(Some(e)),
         }
     }
     let Some((&id, rest)) = edited.split_first() else {

crates/engine/src/view_behaviour_tests.rs

@@ -742,3 +742,32 @@ fn alt_measures_between_layers() {
         assert_eq!(measured(&mut s, p, m), want, "{why}");
     }
 }
+
+#[test]
+fn view_toggles_are_kept_for_the_next_launch() {
+    let mut s = Session::new();
+    // (command, turned to, ViewState field, derivation)
+    let rows: Vec<(&str, bool, fn(&ViewState) -> bool, &str)> = vec![
+        ("view.rulers", true, |v| v.rulers, "rulers shown stay shown"),
+        ("view.pixelGrid", false, |v| v.pixel_grid, "a hidden pixel grid stays hidden"),
+        ("view.layoutGrids", false, |v| v.layout_grids, "hidden layout grids stay hidden"),
+        ("view.snapPixel", false, |v| v.snap_pixel, "snapping to the pixel grid off stays off"),
+    ];
+    for (cmd, on, _, _) in &rows {
+        ex(&mut s, cmd, json!({"on": on}));
+    }
+    // Modes stay with their file: a new one never opens in outline mode or soft-proofing.
+    for cmd in ["view.outlines", "view.outlinesSelection", "view.proofSrgb"] {
+        ex(&mut s, cmd, json!({"on": true}));
+    }
+    // The app writes its preferences as JSON and reads them back at the next launch.
+    let saved = serde_json::to_value(&s.prefs).unwrap();
+    let mut next = Session::empty();
+    next.prefs = serde_json::from_value(saved).unwrap();
+    ex(&mut next, "file.new", json!({}));
+    let view = &next.ds().unwrap().view;
+    for (cmd, on, get, why) in rows {
+        assert_eq!(get(view), on, "{cmd}: {why}");
+    }
+    assert!(!view.outlines && !view.outlines_selection && !view.proof_srgb, "{view:?}");
+}

crates/engine/tests/library_style_acceptance.rs

@@ -1,5 +1,5 @@
 //! Accepting a library update that changes only a paint style refreshes the layers linked to it.
-#![allow(clippy::unwrap_used, clippy::expect_used, clippy::panic)]
+#![allow(clippy::unwrap_used, clippy::expect_used, clippy::panic, clippy::disallowed_methods)]
 
 use figcraft_doc::{NodeId, StyleKind};
 use figcraft_engine::Session;

crates/engine/tests/selection_colors.rs

@@ -0,0 +1,274 @@
+#![allow(clippy::unwrap_used)]
+
+use figcraft_color::Paint;
+use figcraft_doc::NodeId;
+use figcraft_engine::{
+    Session,
+    selection_colors::{SelectionColor, collect},
+};
+use serde_json::{Value, json};
+
+fn run(s: &mut Session, cmd: &str, p: Value) -> Value {
+    s.execute(cmd, &p).unwrap()
+}
+fn rectangle(s: &mut Session, color: &str) -> NodeId {
+    NodeId(run(s, "shape.rectangle", json!({"width":40,"height":40,"props":{"fill":color}}))["id"].as_u64().unwrap())
+}
+fn group(s: &Session, ids: &[NodeId], hex: &str) -> SelectionColor {
+    collect(s.doc().unwrap(), ids).into_iter().find(|g| g.paint.solid_color().is_some_and(|c| c.to_hex() == hex)).unwrap()
+}
+fn fill(s: &Session, id: NodeId) -> String {
+    s.doc().unwrap().node(id).unwrap().fills[0].solid_color().unwrap().to_hex()
+}
+
+#[test]
+fn aggregate_descendants_deduplicate_roots_and_ignore_images_and_hidden_paints() {
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    let b = rectangle(&mut s, "#00ff00");
+    run(&mut s, "stroke.add", json!({"id":b,"color":"#ff0000"}));
+    let parent = NodeId(run(&mut s, "object.group", json!({"ids":[a,b]}))["id"].as_u64().unwrap());
+    let colors = collect(s.doc().unwrap(), &[parent, a]);
+    assert_eq!(colors.len(), 2);
+    assert_eq!(group(&s, &[parent, a], "FF0000").targets.len(), 2);
+    run(&mut s, "fill.add", json!({"id":a,"paint":Paint::image("synthetic",figcraft_color::ImageScaleMode::Fill)}));
+    run(&mut s, "fill.add", json!({"id":a,"paint":{"type":"solid","color":"#0000ff","visible":false}}));
+    assert_eq!(collect(s.doc().unwrap(), &[parent]).len(), 2);
+    run(&mut s, "select.set", json!({"ids":[parent]}));
+    assert_eq!(run(&mut s, "selection.colors", json!({}))["colors"].as_array().unwrap().len(), 2);
+}
+
+#[test]
+fn editing_only_matching_slots_is_one_undo_step_and_keeps_selection() {
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    let b = rectangle(&mut s, "#0000ff");
+    let c = rectangle(&mut s, "#00ff00");
+    run(&mut s, "stroke.add", json!({"id":b,"color":"#ff0000"}));
+    run(&mut s, "select.set", json!({"ids":[a,b]}));
+    let red = group(&s, &[a, b], "FF0000");
+    let before = s.undo_depth();
+    run(&mut s, "selection.setPaint", json!({"targets":red.targets,"paint":"#ffff00"}));
+    assert_eq!(fill(&s, a), "FFFF00");
+    assert_eq!(fill(&s, b), "0000FF");
+    assert_eq!(fill(&s, c), "00FF00");
+    assert_eq!(s.doc().unwrap().node(b).unwrap().strokes[0].solid_color().unwrap().to_hex(), "FFFF00");
+    assert_eq!(s.selection(), vec![a, b]);
+    assert_eq!(s.undo_depth().0, before.0 + 1);
+    s.undo().unwrap();
+    assert_eq!(fill(&s, a), "FF0000");
+    s.redo().unwrap();
+    assert_eq!(fill(&s, a), "FFFF00");
+}
+
+#[test]
+fn live_picker_targets_do_not_expand_when_colors_merge() {
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    let b = rectangle(&mut s, "#0000ff");
+    let red = group(&s, &[a, b], "FF0000");
+    let before = s.undo_depth();
+    s.begin_interaction("Color").unwrap();
+    for hex in ["#0000ff", "#00ff00"] {
+        run(&mut s, "selection.setPaint", json!({"targets":red.targets,"paint":hex}));
+    }
+    s.commit_interaction().unwrap();
+    assert_eq!(fill(&s, a), "00FF00");
+    assert_eq!(fill(&s, b), "0000FF");
+    assert_eq!(s.undo_depth().0, before.0 + 1);
+    s.undo().unwrap();
+    assert_eq!(fill(&s, a), "FF0000");
+}
+
+#[test]
+fn text_range_colors_use_character_offsets_and_preserve_typography() {
+    let mut s = Session::new();
+    let id = NodeId(run(&mut s, "text.create", json!({"text":"Яab","props":{"fill":"#ff0000"}}))["id"].as_u64().unwrap());
+    run(&mut s, "text.style", json!({"id":id,"start":1,"end":2,"fontSize":30,"textFills":["#0000ff"]}));
+    let blue = group(&s, &[id], "0000FF");
+    assert_eq!(blue.targets[0].range, Some((1, 2)));
+    run(&mut s, "selection.setPaint", json!({"targets":blue.targets,"paint":"#00ff00"}));
+    let n = s.doc().unwrap().node(id).unwrap();
+    let t = n.kind.text().unwrap();
+    assert_eq!(t.characters, "Яab");
+    assert_eq!(t.style_at(1).font_size, 30.0);
+    assert_eq!(t.style_at(1).fills.as_ref().unwrap()[0].solid_color().unwrap().to_hex(), "00FF00");
+    assert_eq!(t.style_at(0).fills.as_deref().unwrap_or(&n.fills)[0].solid_color().unwrap().to_hex(), "FF0000");
+    assert_eq!(t.style_at(2).fills.as_deref().unwrap_or(&n.fills)[0].solid_color().unwrap().to_hex(), "FF0000");
+}
+
+#[test]
+fn selecting_color_selects_its_unique_owners_without_document_history() {
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    let b = rectangle(&mut s, "#0000ff");
+    run(&mut s, "stroke.add", json!({"id":a,"color":"#ff0000"}));
+    let red = group(&s, &[a, b], "FF0000");
+    let before = s.undo_depth();
+    run(&mut s, "selection.selectColor", json!({"targets":red.targets}));
+    assert_eq!(s.selection(), vec![a]);
+    assert_eq!(s.undo_depth(), before);
+}
+
+#[test]
+fn applying_color_styles_links_matching_fill_and_stroke_lists_only() {
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    let b = rectangle(&mut s, "#0000ff");
+    run(&mut s, "stroke.add", json!({"id":b,"color":"#ff0000"}));
+    let red = group(&s, &[a, b], "FF0000");
+    let style = run(&mut s, "style.create", json!({"type":"paint","name":"Brand","value":"#00ff00"}))["id"].clone();
+    let before = s.undo_depth();
+    run(&mut s, "selection.applyColorStyle", json!({"targets":red.targets,"style":style}));
+    assert_eq!(fill(&s, a), "00FF00");
+    assert_eq!(fill(&s, b), "0000FF");
+    assert_eq!(s.doc().unwrap().node(a).unwrap().styles.fill.as_deref(), style.as_str());
+    assert_eq!(s.doc().unwrap().node(b).unwrap().styles.stroke.as_deref(), style.as_str());
+    assert_eq!(s.undo_depth().0, before.0 + 1);
+    run(&mut s, "style.update", json!({"style":style,"value":"#ffff00"}));
+    assert_eq!(fill(&s, a), "FFFF00");
+    assert_eq!(fill(&s, b), "0000FF");
+}
+
+#[test]
+fn explicit_color_detaches_its_binding_but_keeps_other_bindings() {
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    run(&mut s, "variable.createCollection", json!({"name":"Theme"}));
+    let v = run(&mut s, "variable.create", json!({"collection":"Theme","name":"Brand","type":"color","value":"#ff0000"}))["id"].clone();
+    run(&mut s, "variable.bind", json!({"id":a,"field":"fill","variable":v}));
+    let red = group(&s, &[a], "FF0000");
+    run(&mut s, "selection.setPaint", json!({"targets":red.targets,"paint":"#0000ff"}));
+    assert_eq!(fill(&s, a), "0000FF");
+    assert!(s.doc().unwrap().node(a).unwrap().bound.is_empty());
+    s.undo().unwrap();
+    assert_eq!(fill(&s, a), "FF0000");
+    assert!(!s.doc().unwrap().node(a).unwrap().bound.is_empty());
+}
+
+#[test]
+fn invalid_or_stale_targets_roll_back_atomically() {
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    let mut red = group(&s, &[a], "FF0000");
+    let mut bad = red.targets[0].clone();
+    bad.index = 999;
+    red.targets.push(bad);
+    let before = s.undo_depth();
+    assert!(s.execute("selection.setPaint", &json!({"targets":red.targets,"paint":"#0000ff"})).is_err());
+    assert_eq!(fill(&s, a), "FF0000");
+    assert_eq!(s.undo_depth(), before);
+    for command in ["selection.setPaint", "selection.selectColor", "selection.applyColorStyle"] {
+        for params in [json!({}), json!({"targets":[]}), json!({"targets":[{"id":a,"fills":true,"index":0,"range":[0,1]}]})] {
+            assert!(s.execute(command, &params).is_err());
+        }
+    }
+}
+
+#[test]
+fn equal_resolved_colors_from_different_styles_or_variables_stay_separate() {
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    let b = rectangle(&mut s, "#ff0000");
+    let c = rectangle(&mut s, "#ff0000");
+    let style = run(&mut s, "style.create", json!({"type":"paint","name":"Brand","value":"#ff0000"}))["id"].clone();
+    run(&mut s, "style.apply", json!({"id":a,"style":style,"target":"fill"}));
+    run(&mut s, "variable.createCollection", json!({"name":"Theme"}));
+    let variable = run(&mut s, "variable.create", json!({"collection":"Theme","name":"Accent","type":"color","value":"#ff0000"}))["id"].clone();
+    run(&mut s, "variable.bind", json!({"id":b,"field":"fill","variable":variable}));
+    let colors = collect(s.doc().unwrap(), &[a, b, c]);
+    assert_eq!(colors.len(), 3);
+    assert_eq!(colors[0].style.as_deref(), style.as_str());
+    assert_eq!(colors[1].variable.as_deref(), variable.as_str());
+    assert!(colors[2].style.is_none() && colors[2].variable.is_none());
+}
+
+#[test]
+fn gradients_and_multiple_paints_are_edited_without_replacing_other_slots() {
+    use figcraft_color::{Color, Gradient, GradientKind};
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    let paint = Paint::gradient(Gradient::default_for(GradientKind::Linear, Color::BLACK));
+    run(&mut s, "fill.add", json!({"id":a,"paint":paint}));
+    let colors = collect(s.doc().unwrap(), &[a]);
+    assert_eq!(colors.len(), 2);
+    let gradient = colors.iter().find(|g| g.paint == paint).unwrap();
+    run(&mut s, "selection.setPaint", json!({"targets":gradient.targets,"paint":"#00ff00"}));
+    let paints = &s.doc().unwrap().node(a).unwrap().fills;
+    assert_eq!(paints.len(), 2);
+    assert_eq!(paints[0].solid_color().unwrap().to_hex(), "FF0000");
+    assert_eq!(paints[1].solid_color().unwrap().to_hex(), "00FF00");
+}
+
+#[test]
+fn masks_and_boolean_operands_are_not_selection_colors() {
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    let b = rectangle(&mut s, "#00ff00");
+    let boolean = NodeId(run(&mut s, "bool.union", json!({"ids":[a,b]}))["id"].as_u64().unwrap());
+    run(&mut s, "fill.set", json!({"id":boolean,"color":"#0000ff"}));
+    let colors = collect(s.doc().unwrap(), &[boolean]);
+    assert_eq!(colors.len(), 1);
+    assert_eq!(colors[0].paint.solid_color().unwrap().to_hex(), "0000FF");
+    s.doc_mut().unwrap().get_mut(boolean).unwrap().is_mask = true;
+    assert!(collect(s.doc().unwrap(), &[boolean]).is_empty());
+}
+
+#[test]
+fn range_edit_keeps_a_node_binding_that_other_characters_inherit() {
+    let mut s = Session::new();
+    let id = NodeId(run(&mut s, "text.create", json!({"text":"abc","props":{"fill":"#ff0000"}}))["id"].as_u64().unwrap());
+    run(&mut s, "variable.createCollection", json!({"name":"Theme"}));
+    let v = run(&mut s, "variable.create", json!({"collection":"Theme","name":"Brand","type":"color","value":"#ff0000"}))["id"].clone();
+    run(&mut s, "variable.bind", json!({"id":id,"field":"fill","variable":v}));
+    run(&mut s, "text.style", json!({"id":id,"start":1,"end":2,"textFills":["#0000ff"]}));
+    let blue = group(&s, &[id], "0000FF");
+    run(&mut s, "selection.setPaint", json!({"targets":blue.targets,"paint":"#00ff00"}));
+    assert!(!s.doc().unwrap().node(id).unwrap().bound.is_empty());
+    assert_eq!(fill(&s, id), "FF0000");
+    assert_eq!(
+        s.doc().unwrap().node(id).unwrap().kind.text().unwrap().style_at(1).fills.as_ref().unwrap()[0].solid_color().unwrap().to_hex(),
+        "00FF00"
+    );
+}
+
+#[test]
+fn selection_color_edits_respect_read_only_version_previews() {
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    run(&mut s, "file.saveVersion", json!({"name":"Before"}));
+    run(&mut s, "version.preview", json!({"index":0}));
+    let red = group(&s, &[a], "FF0000");
+    let before = s.undo_depth();
+    assert!(s.execute("selection.setPaint", &json!({"targets":red.targets,"paint":"#0000ff"})).is_err());
+    assert_eq!(fill(&s, a), "FF0000");
+    assert_eq!(s.undo_depth(), before);
+}
+
+#[test]
+fn opacity_edits_keep_the_color_variable_binding() {
+    let mut s = Session::new();
+    let a = rectangle(&mut s, "#ff0000");
+    run(&mut s, "variable.createCollection", json!({"name":"Theme"}));
+    let v = run(&mut s, "variable.create", json!({"collection":"Theme","name":"Brand","type":"color","value":"#ff0000"}))["id"].clone();
+    run(&mut s, "variable.bind", json!({"id":a,"field":"fill","variable":v}));
+    let mut red = group(&s, &[a], "FF0000");
+    red.paint.opacity = 0.5;
+    run(&mut s, "selection.setPaint", json!({"targets":red.targets,"paint":red.paint}));
+    let n = s.doc().unwrap().node(a).unwrap();
+    assert_eq!(n.fills[0].opacity, 0.5);
+    assert!(!n.bound.is_empty());
+}
+
+#[test]
+fn whole_text_fill_keeps_a_color_style_link() {
+    let mut s = Session::new();
+    let id = NodeId(run(&mut s, "text.create", json!({"text":"Text","props":{"fill":"#ff0000"}}))["id"].as_u64().unwrap());
+    let red = group(&s, &[id], "FF0000");
+    assert_eq!(red.targets[0].range, None);
+    let style = run(&mut s, "style.create", json!({"type":"paint","name":"Brand","value":"#0000ff"}))["id"].clone();
+    run(&mut s, "selection.applyColorStyle", json!({"targets":red.targets,"style":style}));
+    assert_eq!(s.doc().unwrap().node(id).unwrap().styles.fill.as_deref(), style.as_str());
+    run(&mut s, "style.update", json!({"style":style,"value":"#00ff00"}));
+    assert_eq!(fill(&s, id), "00FF00");
+}