fix: reconnect to the Dart VM after mobile: launchApp

README.md

@@ -394,6 +394,8 @@ These Appium commands can work across context
 - `getContexts`
 - `activateApp('appId')`/`mobile:activateApp`
     - `mobile:activateApp` has `skipAttachObservatoryUrl` key to not try to attach to an observatory url. e.g. `driver.execute_script 'mobile:activateApp', {skipAttachObservatoryUrl: true, appId: 'com.android.chrome'}`
+- `mobile:launchApp` (iOS)
+    - Relaunches the app with `arguments`/`environment` via XCUITest, then attaches to the observatory url (`skipAttachObservatoryUrl` is honored as well). Use it instead of `activateApp` when the app needs launch arguments again, e.g. with `appium:dartVmServicePort`: `driver.execute_script 'mobile:launchApp', {bundleId: 'com.example.bundleId', arguments: ['--vm-service-port=8283', '--disable-service-auth-codes']}`
 - `terminateApp('appId')`/`mobile:terminateApp`
 - `installApp(appPath, options)`
 - `getClipboard`

driver/lib/driver.ts

@@ -236,7 +236,7 @@ class FlutterDriver extends BaseDriver<FluttertDriverConstraints> {
   }
 
   public async executeCommand(cmd: string, ...args: [string, [{skipAttachObservatoryUrl: string; any: any}]]) {
-    if (new RegExp(/^[\s]*mobile:[\s]*activateApp$/).test(args[0])) {
+    if (new RegExp(/^[\s]*mobile:[\s]*(activateApp|launchApp)$/).test(args[0])) {
       const {skipAttachObservatoryUrl = false} = args[1][0];
       await this.proxydriver?.executeCommand(cmd, ...args);
       if (skipAttachObservatoryUrl) {

driver/test/mobile-launch-app.test.mjs

@@ -0,0 +1,38 @@
+import assert from 'node:assert/strict';
+import {it, mock} from 'node:test';
+
+import {FlutterDriver} from '../build/lib/driver.js';
+
+const noopLog = {info() {}, debug() {}, warn() {}, error() {}, errorWithException() {}};
+
+// The reconnect that follows the launch fails right away here because no device-log monitor
+// was started, which shows that the driver tried to re-attach to the Dart VM.
+it('forwards mobile: launchApp to XCUITest from the FLUTTER context and reconnects', async () => {
+  const proxydriver = {executeCommand: mock.fn(async () => {})};
+  const params = {bundleId: 'com.example.app', arguments: ['--vm-service-port=9123']};
+
+  await assert.rejects(
+    FlutterDriver.prototype.executeCommand.call(
+      {log: noopLog, currentContext: 'FLUTTER', internalCaps: {platformName: 'iOS'}, proxydriver},
+      'execute',
+      'mobile: launchApp',
+      [params],
+    ),
+    /mandatory syslog service/,
+  );
+
+  assert.deepEqual(proxydriver.executeCommand.mock.calls[0].arguments, ['execute', 'mobile: launchApp', [params]]);
+});
+
+it('skips the reconnect for mobile: launchApp when skipAttachObservatoryUrl is set', async () => {
+  const proxydriver = {executeCommand: mock.fn(async () => {})};
+
+  await FlutterDriver.prototype.executeCommand.call(
+    {log: noopLog, currentContext: 'FLUTTER', internalCaps: {platformName: 'iOS'}, proxydriver},
+    'execute',
+    'mobile: launchApp',
+    [{bundleId: 'com.example.app', skipAttachObservatoryUrl: true}],
+  );
+
+  assert.equal(proxydriver.executeCommand.mock.callCount(), 1);
+});