Smoke tests - run each suite in its own user-data-dir (#125670)

* Initial commit for isolated smoke tests

* Do not wait for the explorer view when restarting

* Debug failed localization test

* User data path suffix length

* Kill server when application exits

* Do not run yarn install

* Refactor application start/stop

* Reverted some changes

* Missed one

* One more change to revert

* Restored one more file

* Pull request feedback

test/smoke/src/utils.ts

@@ -3,7 +3,9 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
+import minimist = require('minimist');
 import { Suite, Context } from 'mocha';
+import { Application, ApplicationOptions } from '../../automation';
 
 export function describeRepeat(n: number, description: string, callback: (this: Suite) => void): void {
 	for (let i = 0; i < n; i++) {
@@ -16,3 +18,25 @@ export function itRepeat(n: number, description: string, callback: (this: Contex
 		it(`${description} (iteration ${i})`, callback);
 	}
 }
+
+export function beforeSuite(opts: minimist.ParsedArgs) {
+	before(async function () {
+		// https://github.com/microsoft/vscode/issues/34988
+		const options = this.defaultOptions as ApplicationOptions;
+		const userDataPathSuffix = [...Array(8)].map(() => Math.random().toString(36)[3]).join('');
+		const userDataDir = options.userDataDir.concat(`-${userDataPathSuffix}`);
+
+		const app = new Application({ ...options, userDataDir });
+		await app!.start(opts.web ? false : undefined);
+		this.app = app;
+	});
+}
+
+export function afterSuite() {
+	after(async function () {
+		const app = this.app as Application;
+		if (app) {
+			await app.stop();
+		}
+	});
+}