do not automatically pop up devtools when running tests

src/vs/code/electron-main/window.ts

@@ -458,7 +458,8 @@ export class VSCodeWindow {
 		this._win.loadURL(this.getUrl(config));
 
 		// Make window visible if it did not open in N seconds because this indicates an error
-		if (!this.environmentService.isBuilt) {
+		// Only do this when running out of sources and not when running tests
+		if (!this.environmentService.isBuilt && !this.environmentService.extensionTestsPath) {
 			this.showTimeoutHandle = setTimeout(() => {
 				if (this._win && !this._win.isVisible() && !this._win.isMinimized()) {
 					this._win.show();

src/vs/workbench/electron-browser/bootstrap/index.js

@@ -139,7 +139,7 @@ function main() {
 
 	window.document.documentElement.setAttribute('lang', locale);
 
-	const enableDeveloperTools = process.env['VSCODE_DEV'] || !!configuration.extensionDevelopmentPath;
+	const enableDeveloperTools = (process.env['VSCODE_DEV'] || !!configuration.extensionDevelopmentPath) && !configuration.extensionTestsPath;
 	const unbind = registerListeners(enableDeveloperTools);
 
 	// disable pinch zoom & apply zoom level early to avoid glitches
@@ -193,7 +193,6 @@ function main() {
 			timers.afterLoadWorkbenchMain = new Date();
 
 			process.lazyEnv.then(function () {
-
 				require('vs/workbench/electron-browser/main')
 					.startup(configuration)
 					.done(function () {
@@ -202,7 +201,6 @@ function main() {
 						onError(error, enableDeveloperTools);
 					});
 			});
-
 		});
 	});
 }