Added handling for multiple '--user-data-dir' to enable Spectron smoke testing in #25291.

src/main.js

@@ -170,8 +170,15 @@ function mkdir(dir) {
 	});
 }
 
+// Because Spectron doesn't allow us to pass a custom user-data-dir,
+// Code receives two of them. Let's just take the first one.
+var userDataDir = args['user-data-dir'];
+if (userDataDir) {
+	userDataDir = typeof userDataDir === 'string' ? userDataDir : userDataDir[0];
+}
+
 // Set userData path before app 'ready' event and call to process.chdir
-var userData = path.resolve(args['user-data-dir'] || paths.getDefaultUserDataPath(process.platform));
+var userData = path.resolve(userDataDir || paths.getDefaultUserDataPath(process.platform));
 app.setPath('userData', userData);
 
 // Update cwd based on environment and platform

src/vs/platform/environment/node/argv.ts

@@ -105,7 +105,14 @@ export function parseCLIProcessArgv(processArgv: string[]): ParsedArgs {
  * Use this to parse code arguments such as `--verbose --wait`
  */
 export function parseArgs(args: string[]): ParsedArgs {
-	return minimist(args, options) as ParsedArgs;
+	const result = minimist(args, options) as ParsedArgs;
+
+	// Because Spectron doesn't allow us to pass a custom user-data-dir,
+	// Code receives two of them. Let's just take the first one.
+	const userDataDir: string | string[] = result['user-data-dir'];
+	result['user-data-dir'] = typeof userDataDir === 'string' ? userDataDir : userDataDir[0];
+
+	return result;
 }
 
 export const optionsHelp: { [name: string]: string; } = {

src/vs/platform/environment/test/node/environmentService.test.ts

@@ -41,4 +41,11 @@ suite('EnvironmentService', () => {
 		assert.equal(parse(['--user-data-dir', './dir'], { cwd: () => '/foo', env: { 'VSCODE_CWD': '/bar' } }), path.resolve('/bar/dir'),
 			'should use VSCODE_CWD as the cwd when --user-data-dir is specified');
 	});
+
+	test('userDataPath should always take the first one', () => {
+		const parse = (a, b: { cwd: () => string, env: { [key: string]: string } }) => parseUserDataDir(parseArgs(a), <any>b);
+
+		assert.equal(parse(['--user-data-dir', './dir1', '--user-data-dir', './dir2'], { cwd: () => '/foo', env: {} }), path.resolve('/foo/dir1'),
+			'should pick first --user-data-dir (dir1)');
+	});
 });