feat(vscode): rs fmt document formatter stack

.vscode/launch.json

@@ -13,6 +13,18 @@
       "args": [
         "--extensionDevelopmentPath=${workspaceFolder}/packages/vscode",
         "--disable-extensions",
+        // An isolated, auto-created profile, so personal user settings
+        // (formatters, format-on-save, keybindings) cannot leak into the
+        // playground. `--user-data-dir` would be the stronger isolation, but
+        // the extension-host debugger strips it; `--profile` is the supported
+        // mechanism for debug launches.
+        "--profile=rstack-playground",
+        // A fresh profile would otherwise prompt for workspace trust and greet
+        // with the welcome tour on every first launch.
+        "--disable-workspace-trust",
+        "--skip-welcome",
+        "--skip-release-notes",
+        "--disable-updates",
         "${workspaceFolder}/packages/vscode/${input:playgroundTarget}"
       ],
       "outFiles": ["${workspaceFolder}/packages/vscode/dist/**/*.js"],

.vscode/tasks.json

@@ -23,7 +23,11 @@
         "background": {
           "activeOnStart": true,
           "beginsPattern": "build started\\.\\.\\.",
-          "endsPattern": "built in"
+          // Not "built in" — that line fires once per target, and the tiny
+          // worker bundle finishes seconds before the extension bundle, which
+          // released the F5 launch against a half-written dist/. This line is
+          // printed once, after every target completed.
+          "endsPattern": "build completed"
         }
       },
       "presentation": {

README.md

@@ -17,7 +17,7 @@ The extension takes its configuration from five sources. The tool-native configs
 | `rslint.config.*` | **Supported.** Diagnostics, quick fixes and the language server, all resolved from the `@rslint/core` installed in your project. |
 | `rstest.config.*` | **Supported.** Test discovery, run and debug, watch mode, coverage and snapshot updates in the Test Explorer. |
 | `define.test()` in `rstack.config.*` | **Supported.** Tests run through the same config shim `rs test` uses, so the editor and the CLI resolve the config identically. |
-| `define.fmt()` in `rstack.config.*` | **Planned.** Detected and reported in the status bar; formatting itself arrives next, first over `rs fmt --stdin-filepath` and later over an `rs fmt` language server. |
+| `define.fmt()` in `rstack.config.*` | **Supported.** Document formatting through the project-local `rs fmt --stdin-filepath`, resolving the config the same way the CLI does; an `rs fmt` language server is the longer-term path. |
 | `define.lint()` in `rstack.config.*` | **Planned.** Linting a project configured only through `rstack.config.*` needs upstream changes in Rslint and rstack-cli before the editor can evaluate it correctly. `rs lint` on the command line is unaffected. |
 
 ## License

packages/vscode/AGENTS.md

@@ -31,7 +31,7 @@ One extension replacing the standalone `rstack.rslint` and `rstack.rstest` exten
 
 - The lint × `rstack.config.*` bridge was built and deliberately removed: a partial editor-side bridge gave wrong results, and a correct one needs upstream work first. `TODO(rstack-bridge)` markers carry the plan. Do not reintroduce a partial bridge.
 - The test × `rstack.config.*` bridge stays thin on purpose: it points the upstream machinery at rstack's shipped shim and lets the shim interpret the config inside the worker, same as the CLI. Never re-implement rstack config semantics in the extension.
-- The fmt stack is a stub on purpose. The MVP will spawn `rs fmt --stdin-filepath` with cwd = the config directory (forced by rs fmt's cwd-only config resolution); the endgame is an upstream LSP, so do not add a warm-process middle tier or "fix" the stub into an error state.
+- The fmt stack is a spawn-per-request `rs fmt --stdin-filepath` MVP. Its cwd is the governing config directory because rs fmt resolves config from cwd only, and formatting errors are log-only by design. The endgame is an upstream LSP, so do not add a warm-process middle tier.
 - `projectModules.ts` has no cache-invalidation hook and restart must not grow one. Node's ESM registry is keyed by resolved URL and process-lifetime, so clearing the local memo hands back the identical module object (verified); a `?epoch=` query does reload the entry but relative specifiers inside it do not inherit the query, yielding a fresh entry over stale dependencies. In-place reinstalls under an unchanged path need a window reload — say so, don't fake it.
 - The VSIX is platform-targeted for exactly one reason: the test stack's AST collection loads a native parser binding. Do not add another native dependency — it multiplies the release matrix.
 

packages/vscode/README.md

@@ -1,6 +1,6 @@
 # Rstack for VS Code
 
-One extension for the whole [Rstack](https://rstack.rs) toolchain: [Rslint](https://github.com/web-infra-dev/rslint) linting, [Rstest](https://github.com/web-infra-dev/rstest) testing, and [rstack-cli](https://github.com/rstackjs/rstack-cli) support (coming soon). It replaces the standalone `rstack.rslint` and `rstack.rstest` extensions.
+One extension for the whole [Rstack](https://rstack.rs) toolchain: [Rslint](https://github.com/web-infra-dev/rslint) linting, [Rstest](https://github.com/web-infra-dev/rstest) testing, and [rstack-cli](https://github.com/rstackjs/rstack-cli) support. It replaces the standalone `rstack.rslint` and `rstack.rstest` extensions.
 
 ## Installation
 
@@ -13,7 +13,7 @@ The extension ships no tool binaries: `@rslint/core`, `@rstest/core` and `rstack
 
 - **Linting (Rslint)** — diagnostics, quick fixes and auto-fix on save via Rslint's language server.
 - **Testing (Rstest)** — a Test Explorer tree built from your test files: run or debug individual tests, suites or files; the tree stays in sync as files change; failed tests show up as editor diagnostics.
-- **rstack-cli** — detected today, integration lands in upcoming releases, starting with formatting.
+- **rstack-cli** — document formatting through the project-local `rs fmt` CLI.
 - **One status bar item** — a single `Rstack` entry shows which tools are active in the current workspace and why.
 
 ## Detection
@@ -38,7 +38,7 @@ The project-resolved packages are checked against a support matrix at runtime; a
 | -------------- | --------- |
 | `@rslint/core` | `>=0.7.2` |
 | `@rstest/core` | `>=0.6.0` |
-| `rstack`       | `>=0.3.2` |
+| `rstack`       | `>=0.3.5` |
 
 ## Auto-fix on save (Rslint)
 
@@ -94,8 +94,9 @@ All settings live under the unified `rstack.*` namespace. There are no `rslint.*
 | `rstack.rstest.debuggerAddress` | — | Debugger address. |
 | `rstack.rstest.terminalShellPath` | — | Shell used by **Run in Terminal**. |
 | `rstack.rstest.terminalShellArgs` | `[]` | Shell args for **Run in Terminal**. |
-| `rstack.fmt.enable` | `true` | Enable/disable the formatter integration (upcoming). |
-| `rstack.fmt.suggestDefaultFormatter` | `true` | Offer to set `editor.defaultFormatter` once rstack-cli is detected. |
+| `rstack.fmt.enable` | `true` | Enable/disable the formatter integration. |
+
+To use `rs fmt` as the formatter for supported documents, opt in through your VS Code settings: `"editor.defaultFormatter": "rstack.rstack"`. The extension never changes `editor.defaultFormatter` itself.
 
 ## Migrating from the standalone extensions
 

packages/vscode/package.json

@@ -334,14 +334,7 @@
             "type": "boolean",
             "default": true,
             "scope": "window",
-            "markdownDescription": "Enable the `rs fmt` document formatter for detected workspace folders. Requires `#rstack.enable#`. This is a window-level kill switch; which folders are formatted is decided by detection. Phase 2 — the formatter is not registered yet."
-          },
-          "rstack.fmt.suggestDefaultFormatter": {
-            "order": 1,
-            "type": "boolean",
-            "default": true,
-            "scope": "resource",
-            "markdownDescription": "Offer a one-time prompt to set Rstack as the workspace `editor.defaultFormatter` when `rs fmt` is detected. The extension never writes `editor.defaultFormatter` without confirmation."
+            "markdownDescription": "Enable the `rs fmt` document formatter for detected workspace folders. Requires `#rstack.enable#`. This is a window-level kill switch; which folders are formatted is decided by detection."
           }
         }
       }

packages/vscode/src/extension.ts

@@ -40,7 +40,7 @@ type Gate =
  */
 class ExtensionShell {
   readonly #channels = new Channels();
-  readonly #statusBar = new StatusBar();
+  readonly #statusBar = new StatusBar(this.#channels.shell);
   readonly #detection: DetectionService;
   readonly #controllers = new Map<StackId, StackController>();
   readonly #subscriptions: vscode.Disposable[] = [];

packages/vscode/src/shared/vendored/loadRstackConfig.ts

@@ -6,9 +6,9 @@
 // explicit-path config loader plus adapter exports, rslint accepting per-root
 // fallback config candidates on `rslint/configRefresh`, and a generic
 // evaluator-module seam shared by the config host and plugin workers). The
-// loader is kept for the phase-2 fmt stack (evaluating `define.fmt()`) and
-// possible future status refinements; today only
-// `nativeTypeStrippingAvailable` is consumed.
+// formatter deliberately leaves `define.fmt()` evaluation to the CLI. This
+// copy remains for the Rslint jiti preflight's `nativeTypeStrippingAvailable`
+// probe and for direct loader unit coverage.
 //
 // Vendored from rstackjs/rstack-cli `packages/rstack/src/config.ts`
 // (origin/main @ 6494ba2, rstack@0.3.2). Only three things differ from upstream:

packages/vscode/src/shared/versionCheck.ts

@@ -11,12 +11,13 @@ import { readPackageJson } from './packageResolve';
  * - `@rslint/core >= 0.7.2` — first version whose package exports
  *   `./config-loader` and `./eslint-plugin`.
  * - `@rstest/core >= 0.6.0` — the existing `MIN_CORE_VERSION` upstream.
- * - `rstack >= 0.3.2` — first release containing `rs fmt --stdin-filepath`.
+ * - `rstack >= 0.3.5` — first release with the full supported config and
+ *   formatter surface.
  */
 export const SUPPORT_MATRIX = {
   '@rslint/core': '>=0.7.2',
   '@rstest/core': '>=0.6.0',
-  rstack: '>=0.3.2',
+  rstack: '>=0.3.5',
 } as const;
 
 export type SupportedPackage = keyof typeof SUPPORT_MATRIX;