feature: add opt-in native TypeScript 7 backend (#736)

* feature: add opt-in native TypeScript 7 backend

* fix: type preference mock arguments

* fix: declare optional backends separately from required language servers

* test: capture native TypeScript UI acceptance pending host release

* fix: type native UI diagnostic expectations

* fix: parse Windows archive listings with CRLF line endings

* fix: register command dispatch before asynchronous backend selection

* fix: register provider dispatch before backend selection

* feature: validate native TypeScript against published host

Author: levivilet

.github/workflows/pr.yml

@@ -40,6 +40,8 @@ jobs:
           THREEJS_ENFORCE_REUSE: 1
       - name: Build
         run: npm run build
+      - name: Verify extension archive excludes native servers
+        run: node scripts/test-extension-archive.mjs
       - name: Build static site
         run: npm run build:static
         env:
@@ -53,6 +55,12 @@ jobs:
         working-directory: ./packages/e2e
         run: sudo npx playwright install-deps chromium firefox webkit
         if: runner.os == 'Linux'
+      - name: Prepare native TypeScript test host
+        run: node scripts/prepare-native-test-host.mjs
+      - name: Run native TypeScript regression
+        run: npm run e2e:native --workspace=packages/e2e -- --trace-renderer-worker
+        env:
+          PLAYWRIGHT_BROWSERS_PATH: 0
       - name: Test persistent file cache and measure diagnostics
         run: node scripts/benchmark-file-cache.mjs
         env:

README.md

@@ -12,3 +12,9 @@ npm test
 ## Credits
 
 This extension is based on https://github.com/microsoft/vscode/tree/main/extensions/typescript-language-features by Microsoft (License MIT)
+
+### TypeScript 7
+
+Set `"typescript.useTs7": true` and reload the window to use LVCE's bundled native TypeScript 7 language server. The default remains the TypeScript web worker. The native server requires a desktop or server host; a static browser deployment cannot launch it. Missing or unsupported native hosts report a language-server error rather than starting a second backend.
+
+The application owns the executable and its standard libraries. No native TypeScript executable is included in `extension.tar.br`. Native mode uses LSP completion, diagnostics, navigation, hover, signature help, rename, symbols, formatting and code actions when the server advertises support. Editor-specific brace, closing-tag, tab and selection providers are unavailable in this mode. Worker performance/cache commands apply only to the default backend. Reloading also disposes the previous server.

package-lock.json

@@ -7,21 +7,27 @@ import { root } from './root.ts'
 const [manifestName, ...args] = process.argv.slice(2)
 const e2ePath = join(root, 'packages', 'e2e')
 const isSmartSelectionE2e = manifestName === 'smart-selection-e2e'
+const isNativeE2e = manifestName === 'native-e2e'
 const isThreeJsE2e = manifestName === 'threejs-e2e'
 const requireFromE2e = createRequire(join(e2ePath, 'package.json'))
 const runnerPath = requireFromE2e.resolve('@lvce-editor/test-with-playwright/bin/test-with-playwright.js')
 const testPath = join(root, '.tmp', 'e2e-manifests', manifestName)
 const testSourcePath = join(e2ePath, 'src')
 const allTestNames = (await readdir(testSourcePath)).filter((name) => !name.startsWith('_'))
-const testNames = isThreeJsE2e
-  ? allTestNames.filter((name) => name === 'typescript.threejs-warm-edits.ts')
-  : isSmartSelectionE2e
-    ? allTestNames.filter(
-        (name) => name.startsWith('typescript.grow-selection') || name === 'typescript.shrink-selection.ts',
-      )
-    : allTestNames.filter(
-        (name) => name !== 'typescript.shrink-selection.ts' && name !== 'typescript.threejs-warm-edits.ts',
-      )
+const testNames = isNativeE2e
+  ? allTestNames.filter((name) => name === 'typescript.native-ts7.ts')
+  : isThreeJsE2e
+    ? allTestNames.filter((name) => name === 'typescript.threejs-warm-edits.ts')
+    : isSmartSelectionE2e
+      ? allTestNames.filter(
+          (name) => name.startsWith('typescript.grow-selection') || name === 'typescript.shrink-selection.ts',
+        )
+      : allTestNames.filter(
+          (name) =>
+            name !== 'typescript.shrink-selection.ts' &&
+            name !== 'typescript.threejs-warm-edits.ts' &&
+            name !== 'typescript.native-ts7.ts',
+        )
 
 await rm(testPath, { force: true, recursive: true })
 await mkdir(join(testPath, 'src'), { recursive: true })

packages/build/src/run-e2e.ts

@@ -4,6 +4,7 @@
   "description": "End-to-end tests for TypeScript language features",
   "main": "index.js",
   "scripts": {
+    "e2e:native": "node ../build/src/run-e2e.ts native-e2e --headless",
     "e2e": "node ../build/src/run-e2e.ts stable-e2e",
     "e2e:headless": "node ../build/src/run-e2e.ts stable-e2e --headless",
     "e2e:firefox:headless": "node ../build/src/run-e2e.ts stable-e2e --browser=firefox --headless",
@@ -20,7 +21,7 @@
   },
   "license": "MIT",
   "devDependencies": {
-    "@lvce-editor/server-smart-selection": "npm:@lvce-editor/server@^0.122.17",
+    "@lvce-editor/server-smart-selection": "npm:@lvce-editor/server@^0.125.8",
     "@lvce-editor/test-with-playwright": "^22.40.2"
   }
 }

packages/e2e/package.json

@@ -0,0 +1,50 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'typescript.native-ts7'
+
+export const test: Test = async ({ Command, Editor, expect, FileSystem, Locator, Main, Settings, Workspace }) => {
+  const root = await FileSystem.getTmpDir({ scheme: 'file' })
+  await FileSystem.writeFile(
+    `${root}/tsconfig.json`,
+    JSON.stringify({ compilerOptions: { strict: true }, files: ['main.ts'] }),
+  )
+  const uri = `${root}/main.ts`
+  await FileSystem.writeFile(uri, 'const value: string = 123;\n')
+  await Settings.update({ 'editor.diagnostics': true, 'typescript.useTs7': true })
+  await Workspace.setUri(root)
+  await Main.openUri(uri)
+  await Command.execute('Editor.waitForDiagnostics')
+  const expectedDiagnostics = [
+    {
+      code: 2322,
+      columnIndex: 6,
+      endColumnIndex: 11,
+      endRowIndex: 0,
+      message: "Type 'number' is not assignable to type 'string'.",
+      rowIndex: 0,
+      source: 'ts',
+      type: 'error',
+      uri,
+    },
+  ] as const
+  await Editor.shouldHaveDiagnostics(expectedDiagnostics)
+  let workerCommandError = ''
+  try {
+    await Command.executeExtensionCommand('typescript.getProjectCacheStatistics')
+  } catch (error) {
+    workerCommandError = String(error)
+  }
+  if (!workerCommandError.includes('command typescript.getProjectCacheStatistics not found')) {
+    throw new Error(
+      `Native mode must dispose worker-only commands: ${workerCommandError || 'worker command succeeded'}`,
+    )
+  }
+  await Editor.setText('const value: string = "valid";\n')
+  await Command.execute('Editor.waitForDiagnostics')
+  await Editor.shouldHaveDiagnostics([])
+  await Editor.setText('const greeting = "hello";\ngreeting.toU')
+  await Editor.setCursor(1, 12)
+  await Editor.openCompletion()
+  const items = Locator('#Completions')
+  await expect(items).toContainText('toUpperCase')
+}

packages/e2e/src/typescript.native-ts7.ts

@@ -28,6 +28,11 @@
       "type": "array",
       "default": [],
       "description": "Prevalidated documents for static demos. Each entry must match the exact document URI, SHA-256 text hash, compiler configuration URI and SHA-256 configuration hash. Only use with fixed, validated project dependencies. Edits and missing evidence resume diagnostics; other language features are unaffected."
+    },
+    "typescript.useTs7": {
+      "type": "boolean",
+      "default": false,
+      "description": "Use the application-bundled TypeScript 7 language server instead of the TypeScript web worker. Requires a native LVCE host. Reload the window after changing this setting."
     }
   },
   "rpc": [
@@ -91,6 +96,10 @@
     {
       "id": "typescript.provideCompletions.typescriptreact",
       "languageId": "typescriptreact"
+    },
+    {
+      "id": "typescript.provideCompletions.javascriptreact",
+      "languageId": "javascriptreact"
     }
   ],
   "diagnosticProviders": [
@@ -105,6 +114,10 @@
     {
       "id": "typescript.provideDiagnostics.typescriptreact",
       "languageId": "typescriptreact"
+    },
+    {
+      "id": "typescript.provideDiagnostics.javascriptreact",
+      "languageId": "javascriptreact"
     }
   ],
   "commands": [
@@ -129,6 +142,10 @@
     {
       "id": "typescript.provideHover.typescriptreact",
       "languageId": "typescriptreact"
+    },
+    {
+      "id": "typescript.provideHover.javascriptreact",
+      "languageId": "javascriptreact"
     }
   ],
   "signatureHelpProviders": [
@@ -143,6 +160,10 @@
     {
       "id": "typescript.provideSignatureHelp.typescriptreact",
       "languageId": "typescriptreact"
+    },
+    {
+      "id": "typescript.provideSignatureHelp.javascriptreact",
+      "languageId": "javascriptreact"
     }
   ],
   "languages": [
@@ -204,5 +225,31 @@
       "fileMatch": "jsconfig.*.json",
       "url": "./schemas/jsconfig.schema.json"
     }
+  ],
+  "optionalLanguageServers": [
+    {
+      "id": "typescript.ts7.javascript",
+      "connectionId": "typescript.ts7",
+      "languageId": "javascript",
+      "activationCommand": "typescript.awaitActivation"
+    },
+    {
+      "id": "typescript.ts7.javascriptreact",
+      "connectionId": "typescript.ts7",
+      "languageId": "javascriptreact",
+      "activationCommand": "typescript.awaitActivation"
+    },
+    {
+      "id": "typescript.ts7.typescript",
+      "connectionId": "typescript.ts7",
+      "languageId": "typescript",
+      "activationCommand": "typescript.awaitActivation"
+    },
+    {
+      "id": "typescript.ts7.typescriptreact",
+      "connectionId": "typescript.ts7",
+      "languageId": "typescriptreact",
+      "activationCommand": "typescript.awaitActivation"
+    }
   ]
 }

packages/extension/extension.json

@@ -1,4 +1,9 @@
-import { activate as activateExtensionApi, registerCommand } from '@lvce-editor/api'
+import {
+  activate as activateExtensionApi,
+  getPreference,
+  registerCommand,
+  registerLanguageServer,
+} from '@lvce-editor/api'
 import * as DiskWatch from '../DiskWatch/DiskWatch.ts'
 import * as Providers from '../Providers/Providers.ts'
 import * as RegisterProviders from '../RegisterProviders/RegisterProviders.ts'
@@ -7,24 +12,65 @@ import * as ShowPerformanceTrace from '../ShowPerformanceTrace/ShowPerformanceTr
 
 const state = {
   isActivated: false,
+  native: false,
+}
+const activation = Promise.withResolvers<void>()
+
+const requireWorkerBackend = async (): Promise<void> => {
+  await activation.promise
+  if (state.native) {
+    throw new Error('This command requires the TypeScript web-worker backend')
+  }
 }
 
 export const activate = async (): Promise<void> => {
   if (state.isActivated) {
-    return
+    return activation.promise
   }
   state.isActivated = true
-  await activateExtensionApi()
-  registerCommand({
-    execute: ShowPerformanceTrace.showPerformanceTrace,
-    id: 'typescript.showPerformanceTrace',
-  })
-  registerCommand({
-    execute: (options?: { readonly waitForIdle?: boolean }) =>
-      Rpc.invoke(options?.waitForIdle ? 'ProjectLifecycle.waitForIdle' : 'ProjectLifecycle.getStatistics'),
-    id: 'typescript.getProjectCacheStatistics',
-  })
-  RegisterProviders.registerProviders(Object.values(Providers))
+  // Observe rejection even when no host request is awaiting readiness yet.
+  void activation.promise.catch(() => {})
+  // Install dispatch before the API creates its initial RPC command map. The
+  // preference round trip must not expose a partially registered extension.
+  registerCommand({ execute: () => activation.promise, id: 'typescript.awaitActivation' })
+  const workerCommands = [
+    registerCommand({
+      execute: async (...args: Parameters<typeof ShowPerformanceTrace.showPerformanceTrace>) => {
+        await requireWorkerBackend()
+        return ShowPerformanceTrace.showPerformanceTrace(...args)
+      },
+      id: 'typescript.showPerformanceTrace',
+    }),
+    registerCommand({
+      execute: async (options?: { readonly waitForIdle?: boolean }) => {
+        await requireWorkerBackend()
+        return Rpc.invoke(options?.waitForIdle ? 'ProjectLifecycle.waitForIdle' : 'ProjectLifecycle.getStatistics')
+      },
+      id: 'typescript.getProjectCacheStatistics',
+    }),
+  ]
+  const workerProviders = RegisterProviders.registerProviders(Object.values(Providers), requireWorkerBackend)
+  const nativeServers = ['javascript', 'javascriptreact', 'typescript', 'typescriptreact'].map((languageId) =>
+    registerLanguageServer({
+      argv: ['--lsp', '--stdio'],
+      id: `typescript.ts7.${languageId}`,
+      languageId,
+      uri: 'lvce-language-server:typescript',
+    }),
+  )
+  try {
+    await activateExtensionApi()
+    state.native = (await getPreference('typescript.useTs7')) === true
+    if (state.native) {
+      for (const registration of [...workerCommands, ...workerProviders]) registration.dispose()
+    } else {
+      for (const server of nativeServers) server.dispose()
+    }
+    activation.resolve()
+  } catch (error) {
+    activation.reject(error)
+    throw error
+  }
 }
 
 export const deactivate = async (): Promise<void> => {