use ESM for HTML/CSS/JSON language servers

[aeschli]

No description provided.

[github-actions]

Screenshot Changes

Base: 985aca65 Current: d8ede0af

Changed (1)

agentSessionsViewer/NeedsInput/Dark

Before	After

[Copilot]

Pull request overview

Updates the built-in HTML/CSS/JSON language server packages to align with an ESM build/output model, including ESM-style import specifiers and ESM esbuild bundles. This fits into the ongoing ESM modernization effort and unblocks newer *-languageservice “next” packages for the servers.

Changes:

• Switch server TypeScript compilation targets to ESM (module: "esnext") and update internal relative imports to include .js.
• Build node + browser server bundles as ESM via esbuild (format: "esm") and add a Node createRequire banner for CJS dependencies.
• Bump vscode-*-languageservice dependencies to *-next.* versions for HTML/CSS/JSON servers.

Show a summary per file

File	Description
extensions/json-language-features/server/tsconfig.json	Switch JSON server TS emit to ESM (module: esnext).
extensions/json-language-features/server/src/utils/validation.ts	Update relative imports to .js for ESM compatibility.
extensions/json-language-features/server/src/utils/runner.ts	Update relative import to .js for ESM compatibility.
extensions/json-language-features/server/src/node/jsonServerMain.ts	Update relative imports to .js for ESM compatibility.
extensions/json-language-features/server/src/jsonServer.ts	Update relative imports to .js for ESM compatibility.
extensions/json-language-features/server/src/browser/jsonServerMain.ts	Update relative import to .js for ESM compatibility.
extensions/json-language-features/server/package.json	Bump vscode-json-languageservice to 6.0.0-next.1; adjust install script to @next.
extensions/json-language-features/server/package-lock.json	Lockfile updates for vscode-json-languageservice@6.0.0-next.1 and transitive deps.
extensions/json-language-features/esbuild.mts	Build JSON node server bundle as ESM + add createRequire banner/externalization.
extensions/json-language-features/esbuild.browser.mts	Build JSON browser worker bundle as ESM.
extensions/html-language-features/server/tsconfig.json	Switch HTML server TS emit to ESM (module: esnext).
extensions/html-language-features/server/test/index.js	Convert HTML server test runner to ESM (import + import.meta.dirname).
extensions/html-language-features/server/src/utils/validation.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/utils/runner.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/src/utils/positions.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/src/utils/documentContext.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/src/test/words.test.ts	Update imports and path resolution for ESM (import.meta.dirname).
extensions/html-language-features/server/src/test/semanticTokens.test.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/test/selectionRanges.test.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/test/rename.test.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/test/formatting.test.ts	Update imports and fixture paths for ESM (import.meta.dirname).
extensions/html-language-features/server/src/test/folding.test.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/test/embedded.test.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/test/documentContext.test.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/src/test/completions.test.ts	Update relative imports and fixture root path for ESM (import.meta.dirname).
extensions/html-language-features/server/src/requests.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/src/node/nodeFs.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/src/node/htmlServerMain.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/modes/semanticTokens.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/modes/selectionRanges.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/modes/languageModes.ts	Update relative imports to .js and adjust capability typing/exports.
extensions/html-language-features/server/src/modes/javascriptSemanticTokens.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/src/modes/javascriptMode.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/modes/javascriptLibs.ts	Switch __dirname usage to import.meta.dirname for ESM.
extensions/html-language-features/server/src/modes/htmlMode.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/src/modes/htmlFolding.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/src/modes/formatting.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/modes/embeddedSupport.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/src/modes/cssMode.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/htmlServer.ts	Update relative imports to .js for ESM compatibility.
extensions/html-language-features/server/src/customData.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/src/browser/htmlServerMain.ts	Update relative import to .js for ESM compatibility.
extensions/html-language-features/server/package.json	Mark HTML server package as ESM (type: module) and bump language service deps to next.
extensions/html-language-features/server/package-lock.json	Lockfile updates for bumped HTML/CSS language service deps.
extensions/html-language-features/esbuild.mts	Build HTML node server bundle as ESM + add createRequire banner/externalization.
extensions/html-language-features/esbuild.browser.mts	Build HTML browser worker bundle as ESM.
extensions/html-language-features/client/tsconfig.json	Switch HTML client TS config to nodenext module + resolution.
extensions/css-language-features/server/tsconfig.json	Switch CSS server TS emit to ESM (module: esnext).
extensions/css-language-features/server/src/utils/validation.ts	Update relative imports to .js for ESM compatibility.
extensions/css-language-features/server/src/utils/runner.ts	Update relative import to .js for ESM compatibility.
extensions/css-language-features/server/src/utils/documentContext.ts	Update relative import to .js for ESM compatibility.
extensions/css-language-features/server/src/test/links.test.ts	Update imports and path resolution for ESM (import.meta.dirname).
extensions/css-language-features/server/src/test/completion.test.ts	Update imports and path resolution for ESM (import.meta.dirname).
extensions/css-language-features/server/src/requests.ts	Update relative import to .js for ESM compatibility.
extensions/css-language-features/server/src/node/nodeFs.ts	Update relative import to .js for ESM compatibility.
extensions/css-language-features/server/src/node/cssServerMain.ts	Update relative imports to .js for ESM compatibility.
extensions/css-language-features/server/src/customData.ts	Update relative import to .js for ESM compatibility.
extensions/css-language-features/server/src/cssServer.ts	Update relative imports to .js for ESM compatibility.
extensions/css-language-features/server/src/browser/cssServerMain.ts	Update relative import to .js for ESM compatibility.
extensions/css-language-features/server/package.json	Bump vscode-css-languageservice to 7.0.0-next.1; adjust install script to @next.
extensions/css-language-features/server/package-lock.json	Lockfile updates for bumped CSS language service deps.
extensions/css-language-features/esbuild.mts	Build CSS node server bundle as ESM + add createRequire banner/externalization.
extensions/css-language-features/esbuild.browser.mts	Build CSS browser worker bundle as ESM.

Copilot's findings

Files not reviewed (3)

• extensions/css-language-features/server/package-lock.json: Language not supported
• extensions/html-language-features/server/package-lock.json: Language not supported
• extensions/json-language-features/server/package-lock.json: Language not supported

Comments suppressed due to low confidence (7)

extensions/html-language-features/esbuild.browser.mts:113

• The browser server bundle is now built as ESM (format: 'esm'), but the web extension clients create the worker using new Worker(url) (classic worker). Classic workers cannot execute ESM output. Either switch the worker creation to { type: 'module' } in the browser client, or keep the browser server build in a classic-script format.

	// Build server
	run({
		platform: 'browser',
		format: 'esm',
		entryPoints: {
			'htmlServerMain': path.join(extensionRoot, 'server', 'src', 'browser', 'htmlServerWorkerMain.ts'),
		},
		srcDir: path.join(extensionRoot, 'server', 'src'),
		outdir: path.join(extensionRoot, 'server', 'dist', 'browser'),
		additionalOptions: {
			tsconfig: path.join(extensionRoot, 'server', 'tsconfig.browser.json'),
			plugins: [javaScriptLibsPlugin()],
		},
	}, process.argv),
]);

extensions/css-language-features/server/tsconfig.json:16

• With module: "esnext" and the new relative imports using explicit .js extensions in this project, TypeScript needs Node-style ESM resolution (e.g. moduleResolution: "nodenext" / "node16", or switching module to "nodenext"). Without that, TS will try to resolve ./foo.js as an actual .js source file and the build is expected to fail.

		"lib": [
			"ES2024",
			"WebWorker"
		],
		"module": "esnext",
		"types": [
			"node"
		],
		"typeRoots": [
			"../node_modules/@types"
		]

extensions/html-language-features/server/tsconfig.json:17

• With module: "esnext" and the new relative imports using explicit .js extensions in this project, TypeScript needs Node-style ESM resolution (e.g. moduleResolution: "nodenext" / "node16", or switching module to "nodenext"). Without that, TS will try to resolve ./foo.js as an actual .js source file and the build is expected to fail.
  extensions/css-language-features/esbuild.browser.mts:33
• The browser server bundle is now built as ESM (format: 'esm'), but the web extension clients create the worker using new Worker(url) (classic worker). Classic workers cannot execute ESM output. Either switch the worker creation to { type: 'module' } in the browser client, or keep the browser server build in a classic-script format.

	// Build server
	run({
		platform: 'browser',
		format: 'esm',
		entryPoints: {
			'cssServerMain': path.join(extensionRoot, 'server', 'src', 'browser', 'cssServerWorkerMain.ts'),
		},
		srcDir: path.join(extensionRoot, 'server', 'src'),
		outdir: path.join(extensionRoot, 'server', 'dist', 'browser'),
		additionalOptions: {

extensions/json-language-features/esbuild.browser.mts:35

• The browser server bundle is now built as ESM (format: 'esm'), but the web extension clients create the worker using new Worker(url) (classic worker). Classic workers cannot execute ESM output. Either switch the worker creation to { type: 'module' } in the browser client, or keep the browser server build in a classic-script format.
  extensions/json-language-features/server/tsconfig.json:18
• With module: "esnext" and the new relative imports using explicit .js extensions in this project, TypeScript needs Node-style ESM resolution (e.g. moduleResolution: "nodenext" / "node16", or switching module to "nodenext"). Without that, TS will try to resolve ./foo.js as an actual .js source file and the build is expected to fail.
  extensions/json-language-features/server/package.json:22
• This server package is now being built/emitted as ESM (tsconfig module: esnext, .js import specifiers, and esbuild format: 'esm'), but the package remains CommonJS (no type: "module"). This is also incompatible with the current CLI entrypoint (bin/vscode-json-languageserver) which uses require('../out/node/jsonServerMain'). Either switch the package + bin wrapper to ESM (or add a .cjs wrapper), or keep the emitted server entrypoint as CJS.

• Files reviewed: 60/63 changed files
• Comments generated: 4