run tests in a separate user data dir by default

Fixes microsoft/vscode#137678

Author: connor4312

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+### 2.0.0 | 2021-12-14
+
+- Run tests using a separate instance of VS Code by default. This can be disabled by setting `reuseMachineInstall: true`.
+
 ### 1.6.2 | 2021-07-15
 
 - Add `--disable-workspace-trust` flag when running tests by default

lib/download.ts

@@ -170,14 +170,16 @@ function spawnDecompressorChild(command: string, args: ReadonlyArray<string>, in
 	})
 }
 
+export const defaultCachePath = path.resolve(extensionRoot, '.vscode-test');
+
 /**
  * Download and unzip a copy of VS Code.
  * @returns Promise of `vscodeExecutablePath`.
  */
 export async function download(options?: Partial<DownloadOptions>): Promise<string> {
 	let version = options?.version;
-	let platform = options?.platform ?? systemDefaultPlatform;
-	let cachePath = options?.cachePath ?? path.resolve(extensionRoot, '.vscode-test');
+	const platform = options?.platform ?? systemDefaultPlatform;
+	const cachePath = options?.cachePath ?? defaultCachePath;
 
 	if (version) {
 		if (version === 'stable') {
@@ -258,4 +260,4 @@ export async function download(options?: Partial<DownloadOptions>): Promise<stri
  */
 export async function downloadAndUnzipVSCode(version?: DownloadVersion, platform: DownloadPlatform = systemDefaultPlatform): Promise<string> {
 	return await download({ version, platform });
-}
+}

lib/runTest.ts

@@ -4,7 +4,8 @@
  *--------------------------------------------------------------------------------------------*/
 
 import * as cp from 'child_process';
-import { downloadAndUnzipVSCode, DownloadVersion, DownloadPlatform } from './download';
+import * as path from 'path';
+import { downloadAndUnzipVSCode, DownloadVersion, DownloadPlatform, defaultCachePath } from './download';
 
 export interface TestOptions {
 	/**
@@ -37,6 +38,15 @@ export interface TestOptions {
 	 */
 	platform?: DownloadPlatform;
 
+	/**
+	 * Whether VS Code should be launched using default settings and extensions
+	 * installed on this machine. If `false`, then separate directories will be
+	 * used inside the `.vscode-test` folder within the project.
+	 *
+	 * Defaults to `false`.
+	 */
+	reuseMachineInstall?: boolean;
+
 	/**
 	 * Absolute path to the extension root. Passed to `--extensionDevelopmentPath`.
 	 * Must include a `package.json` Extension Manifest.
@@ -91,6 +101,8 @@ export async function runTests(options: TestOptions): Promise<number> {
 	let args = [
 		// https://github.com/microsoft/vscode/issues/84238
 		'--no-sandbox',
+		'--skip-welcome',
+		'--skip-release-notes',
 		'--disable-workspace-trust',
 		'--extensionDevelopmentPath=' + options.extensionDevelopmentPath,
 		'--extensionTestsPath=' + options.extensionTestsPath
@@ -100,9 +112,23 @@ export async function runTests(options: TestOptions): Promise<number> {
 		args = options.launchArgs.concat(args);
 	}
 
+	if (!options.reuseMachineInstall) {
+		if (!hasArg('extensions-dir', args)) {
+			args.push(`--extensions-dir=${path.join(defaultCachePath, 'extensions')}`)
+		}
+
+		if (!hasArg('user-data-dir', args)) {
+			args.push(`--user-data-dir=${path.join(defaultCachePath, 'user-data')}`)
+		}
+	}
+
 	return innerRunTests(options.vscodeExecutablePath, args, options.extensionTestsEnv);
 }
 
+function hasArg(argName: string, argList: readonly string[]) {
+	return argList.some(a => a === `--${argName}` || a.startsWith(`--${argName}=`));
+}
+
 async function innerRunTests(
 	executable: string,
 	args: string[],