[flutter_plugin_tools] Check for FlutterTestRunner in FTL tests (#4531)

stuartmorgan-g · web-flow · commit aa8095470117 · 2021-11-23T18:52:01.000-08:00
When running via Firebase Test Lab, ensure that there is a test using `FlutterTestRunner`. This ensures that a plugin can't silently not run any of the Dart integration test on Android by having some other native integration test. Fixes flutter/flutter#93952
diff --git a/script/tool/CHANGELOG.md b/script/tool/CHANGELOG.md
@@ -1,3 +1,7 @@
+## NEXT
+
+- Ensures that `firebase-test-lab` runs include an `integration_test` runner.
+
 ## 0.7.3
 
 - `native-test` now builds unit tests before running them on Windows and Linux,
diff --git a/script/tool/lib/src/firebase_test_lab_command.dart b/script/tool/lib/src/firebase_test_lab_command.dart
@@ -127,16 +127,24 @@ class FirebaseTestLabCommand extends PackageLoopingCommand {
           '${example.displayName} does not support Android.');
     }
 
-    if (!androidDirectory
+    final Directory uiTestDirectory = androidDirectory
         .childDirectory('app')
         .childDirectory('src')
-        .childDirectory('androidTest')
-        .existsSync()) {
+        .childDirectory('androidTest');
+    if (!uiTestDirectory.existsSync()) {
       printError('No androidTest directory found.');
       return PackageResult.fail(
           <String>['No tests ran (use --exclude if this is intentional).']);
     }
 
+    // Ensure that the Dart integration tests will be run, not just native UI
+    // tests.
+    if (!await _testsContainDartIntegrationTestRunner(uiTestDirectory)) {
+      printError('No integration_test runner found. '
+          'See the integration_test package README for setup instructions.');
+      return PackageResult.fail(<String>['No integration_test runner.']);
+    }
+
     // Ensures that gradle wrapper exists
     final GradleProject project = GradleProject(example.directory,
         processRunner: processRunner, platform: platform);
@@ -280,4 +288,19 @@ class FirebaseTestLabCommand extends PackageLoopingCommand {
             file is File && file.basename.endsWith('_test.dart'))
         .cast<File>();
   }
+
+  /// Returns true if any of the test files in [uiTestDirectory] contain the
+  /// annotation that means that the test will reports the results of running
+  /// the Dart integration tests.
+  Future<bool> _testsContainDartIntegrationTestRunner(
+      Directory uiTestDirectory) async {
+    return uiTestDirectory
+        .list(recursive: true, followLinks: false)
+        .where((FileSystemEntity entity) => entity is File)
+        .cast<File>()
+        .any((File file) {
+      return file.basename.endsWith('.java') &&
+          file.readAsStringSync().contains('@RunWith(FlutterTestRunner.class)');
+    });
+  }
 }
diff --git a/script/tool/test/firebase_test_lab_command_test.dart b/script/tool/test/firebase_test_lab_command_test.dart
