`code --add` breaks if executed repeatedly (fixes #38138)

src/vs/workbench/electron-browser/window.ts

@@ -45,6 +45,7 @@ import { RunOnceScheduler } from 'vs/base/common/async';
 import { IDisposable, dispose } from 'vs/base/common/lifecycle';
 import { ConfigurationTarget, IConfigurationChangeEvent } from 'vs/platform/configuration/common/configuration';
 import { LifecyclePhase, ILifecycleService } from 'vs/platform/lifecycle/common/lifecycle';
+import { IWorkspaceFolderCreationData } from 'vs/platform/workspaces/common/workspaces';
 
 const TextInputActions: IAction[] = [
 	new Action('undo', nls.localize('undo', "Undo"), null, true, () => document.execCommand('undo') && TPromise.as(true)),
@@ -68,6 +69,9 @@ export class ElectronWindow extends Themable {
 
 	private previousConfiguredZoomLevel: number;
 
+	private addFoldersScheduler: RunOnceScheduler;
+	private pendingFoldersToAdd: IAddFoldersRequest[];
+
 	constructor(
 		shellContainer: HTMLElement,
 		@IWorkbenchEditorService private editorService: IWorkbenchEditorService,
@@ -96,6 +100,10 @@ export class ElectronWindow extends Themable {
 		this.touchBarUpdater = new RunOnceScheduler(() => this.doSetupTouchbar(), 300);
 		this.toUnbind.push(this.touchBarUpdater);
 
+		this.pendingFoldersToAdd = [];
+		this.addFoldersScheduler = new RunOnceScheduler(() => this.doAddFolders(), 100);
+		this.toUnbind.push(this.addFoldersScheduler);
+
 		this.registerListeners();
 		this.create();
 	}
@@ -180,7 +188,7 @@ export class ElectronWindow extends Themable {
 		ipc.on('vscode:openFiles', (_event: any, request: IOpenFileRequest) => this.onOpenFiles(request));
 
 		// Support addFolders event if we have a workspace opened
-		ipc.on('vscode:addFolders', (_event: any, request: IAddFoldersRequest) => this.onAddFolders(request));
+		ipc.on('vscode:addFolders', (_event: any, request: IAddFoldersRequest) => this.onAddFoldersRequest(request));
 
 		// Message support
 		ipc.on('vscode:showInfoMessage', (_event: any, message: string) => {
@@ -394,8 +402,25 @@ export class ElectronWindow extends Themable {
 		});
 	}
 
-	private onAddFolders(request: IAddFoldersRequest): void {
-		const foldersToAdd = request.foldersToAdd.map(folderToAdd => ({ uri: URI.file(folderToAdd.filePath) }));
+	private onAddFoldersRequest(request: IAddFoldersRequest): void {
+
+		// Buffer all pending requests
+		this.pendingFoldersToAdd.push(request);
+
+		// Delay the adding of folders a bit to buffer in case more requests are coming
+		if (!this.addFoldersScheduler.isScheduled()) {
+			this.addFoldersScheduler.schedule();
+		}
+	}
+
+	private doAddFolders(): void {
+		const foldersToAdd: IWorkspaceFolderCreationData[] = [];
+
+		this.pendingFoldersToAdd.forEach(request => {
+			foldersToAdd.push(...request.foldersToAdd.map(folderToAdd => ({ uri: URI.file(folderToAdd.filePath) })));
+		});
+
+		this.pendingFoldersToAdd = [];
 
 		this.workspaceEditingService.addFolders(foldersToAdd).done(null, errors.onUnexpectedError);
 	}