add markdown-language-features to sqlops (#2338)

extensions/markdown-language-features/src/commandManager.ts

@@ -0,0 +1,36 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import * as vscode from 'vscode';
+
+export interface Command {
+	readonly id: string;
+
+	execute(...args: any[]): void;
+}
+
+export class CommandManager {
+	private readonly commands = new Map<string, vscode.Disposable>();
+
+	public dispose() {
+		for (const registration of this.commands.values()) {
+			registration.dispose();
+		}
+		this.commands.clear();
+	}
+
+	public register<T extends Command>(command: T): T {
+		this.registerCommand(command.id, command.execute, command);
+		return command;
+	}
+
+	private registerCommand(id: string, impl: (...args: any[]) => void, thisArg?: any) {
+		if (this.commands.has(id)) {
+			return;
+		}
+
+		this.commands.set(id, vscode.commands.registerCommand(id, impl, thisArg));
+	}
+}