[einari]

The Screenplay VS Code extension now opens .play files on the Cratis event model board, the board Cratis Studio draws. A new TypeScript compiler for Screenplay draws it.

Added

• A .play file opens on the event model board by default and redraws as you edit. Show Source opens the text beside the board, Open Event Model Board goes back, and Reopen Editor With… still offers the text editor. See VS Code extension. (Open .play files on the event model board in the VS Code extension #322)
• A file inside a folder application, the folder holding an application.play, shows the whole application on the board. This includes unsaved edits to any of its files.
• Errors in the model are listed above the board and link to the line, while the board still draws everything that could be read.
• A TypeScript compiler for Screenplay, shipped with the extension. It parses .play documents and folders into the same syntax tree as the C# compiler, with the same visitors and walker. It reports the same diagnostics as the C# compiler for the constructs it reads. See TypeScript compiler.

[einari]

Notes for reviewers

What was verified, and how:

• TypeScript specs: yarn build, yarn lint:ci and yarn test pass for the compiler (72 specs), the event model mapping (18), the language service (66) and the extension (63). They were also run from a clean worktree.
• C# against TypeScript: the new spec Syntax/Serialization/for_SyntaxJson/when_holding_the_typescript_compiler_to_it holds the C# compiler's SyntaxJson to the golden syntax the TypeScript compiler writes for six corpus documents. It passed in .NET Build (4,841 specs, 0 failed) on 42eba1c.
• Board schema: every .play file in the repository maps into a document that the published @cratis/event-models 0.106.0 JSON Schema accepts. The check is not vacuous: a planted bad id and a bad slice type were both reported.
• Rendering: the webview bundle was rendered in headless Chromium under the real content security policy. It draws the invoicing sample with one canvas and no page errors. Pixi needs pixi.js/unsafe-eval to run without 'unsafe-eval' in the CSP.
• Packaging: the VSIX packages at 673 KB.

Not verified here:

• The custom editor inside a real VS Code. The container cannot download VS Code. Please try it with F5, or by installing the VSIX: open a .play file, edit it beside the board, and open a file of a folder application.

Decisions worth a look:

• Dark only. The board is always dark. Its header labels are colored for a dark surface (for example #ffffffb3) rather than drawn from the theme tokens, so on a light background they are unreadable. Studio's viewer is dark only for the same reason. Following the editor theme needs that change in @cratis/event-models.
• Private packages. @cratis/screenplay-compiler and @cratis/screenplay-event-models are private. The extension bundles them, and publishing them to npm needs trusted publishing configured for each new package first.
• Pre-existing failure. The root yarn build fails in the screenplay-editor demo app on a monaco-editor type mismatch between workspaces. This PR does not touch that app. The new JavaScript Build workflow builds the packages it depends on explicitly, and lints and tests every workspace.

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Generated by Claude Code

[einari]

Update for reviewers

Root workspace fixed. yarn build and yarn compile both pass from the root now, and the JavaScript Build workflow runs the root build, compile, lint:ci and test on every pull request. Two failures predated this PR:

• the editor demo pinned monaco-editor 0.52 against the language service's 0.55
• a language service spec asserted on a possibly undefined value

Diagnostics held to C#. Conformance/diagnostics.json lists 112 invalid documents with the code, line and order of every diagnostic. The TypeScript spec and a new C# spec (when_holding_the_typescript_compiler_to_its_diagnostics) hold both compilers to it, and it covers every code the TypeScript parser can report. Writing it led to porting the C# checks the first version skipped inside modeled constructs:

• concept attribute reasons
• an empty validate in an enumeration
• variant entering events
• tags
• $context paths
• structured values

Syntax, tags and structured values. Event tags and {...} / [...] values are now read into the tree. The golden syntax was regenerated, and the diff only adds those.

Coverage, enforced. Both packages run their specs with coverage thresholds, and a planted uncovered file fails the run.

Package	Lines	Branches	Specs
Compiler	99.9%	96.9%	240
Event model mapping	100%	96.3%	37

The walker spec checks that the walker visits exactly the nodes the tree holds, kind by kind.

Still untested by specs: the extension's VS Code glue (BoardRefresh, boardSources, the editor provider) and the React webview. The pure parts of the extension (findApplicationRoot, boardFor, boardHtml) are covered, and the webview was rendered in headless Chromium.

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Generated by Claude Code