feat(language-service): add support for executeCommand handler

packages/language-server/lib/register/registerLanguageFeatures.ts

@@ -31,6 +31,7 @@ export function registerLanguageFeatures(server: LanguageServer) {
 		semanticTokensProvider,
 		diagnosticProvider,
 		inlayHintProvider,
+		executeCommandProvider,
 		experimental,
 	} = server.initializeResult.capabilities;
 
@@ -401,6 +402,17 @@ export function registerLanguageFeatures(server: LanguageServer) {
 			});
 		});
 	}
+	if (executeCommandProvider) {
+		server.connection.onExecuteCommand(async (params, token) => {
+			for (const languageService of await server.project.getExistingLanguageServices()) {
+				if (languageService.executeCommand && languageService.getCommands().includes(params.command)) {
+					try {
+						return await languageService.executeCommand(params.command, params.arguments ?? [], token);
+					} catch { }
+				}
+			}
+		});
+	}
 	if (typeof inlayHintProvider === 'object' && inlayHintProvider.resolveProvider) {
 		server.connection.languages.inlayHint.resolve(async (hint, token) => {
 			return await lastInlayHintLs?.resolveInlayHint(hint, token) ?? hint;

packages/language-server/lib/server.ts

@@ -186,6 +186,11 @@ export function createServerBase(
 					moreTriggerCharacter: [...new Set(capabilitiesArr.map(data => data.documentOnTypeFormattingProvider?.triggerCharacters ?? []).flat())].slice(1),
 				}
 				: undefined,
+			executeCommandProvider: capabilitiesArr.some(data => data.executeCommandProvider)
+				? {
+					commands: [...new Set(capabilitiesArr.map(data => data.executeCommandProvider?.commands ?? []).flat())],
+				}
+				: undefined,
 		};
 
 		if (!status.pullModelDiagnostics && status.initializeResult.capabilities.diagnosticProvider) {

packages/language-service/lib/languageService.ts

@@ -38,6 +38,7 @@ import * as documentLinkResolve from './features/resolveDocumentLink';
 import * as inlayHintResolve from './features/resolveInlayHint';
 import * as workspaceSymbolResolve from './features/resolveWorkspaceSymbol';
 import type { LanguageServiceContext, LanguageServiceEnvironment, LanguageServicePlugin } from './types';
+import { NoneCancellationToken } from './utils/cancellation';
 import { UriMap, createUriMap } from './utils/uriMap';
 
 export type LanguageService = ReturnType<typeof createLanguageServiceBase>;
@@ -188,11 +189,24 @@ function createLanguageServiceBase(
 				tokenTypes: [...new Set(tokenTypes)],
 			};
 		},
+		getCommands: () => plugins.map(plugin => plugin.capabilities.executeCommandProvider?.commands ?? []).flat(),
 		getTriggerCharacters: () => plugins.map(plugin => plugin.capabilities.completionProvider?.triggerCharacters ?? []).flat(),
 		getAutoFormatTriggerCharacters: () => plugins.map(plugin => plugin.capabilities.documentOnTypeFormattingProvider?.triggerCharacters ?? []).flat(),
 		getSignatureHelpTriggerCharacters: () => plugins.map(plugin => plugin.capabilities.signatureHelpProvider?.triggerCharacters ?? []).flat(),
 		getSignatureHelpRetriggerCharacters: () => plugins.map(plugin => plugin.capabilities.signatureHelpProvider?.retriggerCharacters ?? []).flat(),
 
+		executeCommand(command: string, args: any[], token = NoneCancellationToken) {
+			for (const plugin of context.plugins) {
+				if (context.disabledServicePlugins.has(plugin[1])) {
+					continue;
+				}
+				if (!plugin[1].executeCommand || !plugin[0].capabilities.executeCommandProvider?.commands.includes(command)) {
+					continue;
+				}
+				return plugin[1].executeCommand(command, args, token);
+			}
+		},
+
 		getDocumentFormattingEdits: format.register(context),
 		getFoldingRanges: foldingRanges.register(context),
 		getSelectionRanges: selectionRanges.register(context),

packages/language-service/lib/types.ts

@@ -83,6 +83,9 @@ export type SemanticToken = [
 export interface LanguageServicePlugin<P = any> {
 	name?: string;
 	capabilities: {
+		executeCommandProvider?: {
+			commands: string[];
+		};
 		selectionRangeProvider?: boolean;
 		foldingRangeProvider?: boolean;
 		linkedEditingRangeProvider?: boolean;
@@ -133,8 +136,8 @@ export interface LanguageServicePlugin<P = any> {
 			codeActionKinds?: string[];
 			resolveProvider?: boolean;
 		};
-		// TODO: interFileDependencies
 		diagnosticProvider?: {
+			// TODO: interFileDependencies
 			workspaceDiagnostics?: boolean;
 		};
 		fileReferencesProvider?: boolean;
@@ -151,6 +154,7 @@ export interface EmbeddedCodeFormattingOptions {
 export interface LanguageServicePluginInstance<P = any> {
 	provide?: P;
 	isAdditionalCompletion?: boolean; // volar specific
+	executeCommand?(command: string, args: any[], token: vscode.CancellationToken): ProviderResult<any>;
 	provideHover?(document: TextDocument, position: vscode.Position, token: vscode.CancellationToken): NullableProviderResult<vscode.Hover>;
 	provideDocumentSymbols?(document: TextDocument, token: vscode.CancellationToken): NullableProviderResult<vscode.DocumentSymbol[]>;
 	provideDocumentHighlights?(document: TextDocument, position: vscode.Position, token: vscode.CancellationToken): NullableProviderResult<vscode.DocumentHighlight[]>;