Ensure that integration tests are actually being run (flutter#3857)

Many of our integration tests weren't actually being run on CI because they were in the wrong place and/or missing the driver file, and it seems we've just never noticed. This makes a number of changes:
- Ensures that all packages with integration tests also have a driver file in the right location.
  - Also standardizes the format of those files, as the boilerplate `main()` is available in `integration_test`.
- Ensures that all integration_test directories are in the right place.
  - In a couple of places, removes a duplicate copy of the integration test file.
- Makes it an error for a plugin that's not excluded to not have integration tests, so this can't easily happen again.
- Adds logging of what's being run and skipped, so if something does go wrong in the future it's easy to determine what from the logs.
  - Excludes `*_platform_interface` since the logging was (potentially confusingly) reporting that they were skipped because they don't support the current platform. Skipping them is correct, just not for that reason.
- Excludes the plugins that currently have no integration tests, with references to issues about adding them.

Fixes flutter/flutter#81929

Author: stuartmorgan-g

.cirrus.yml

@@ -112,7 +112,7 @@ task:
       build_script:
         - flutter config --enable-linux-desktop
         - ./script/tool_runner.sh build-examples --linux
-      test_script:
+      drive_script:
         - xvfb-run ./script/tool_runner.sh drive-examples --linux
 
 # Heavy-workload Linux tasks.
@@ -167,6 +167,8 @@ task:
     ### Web tasks ###
     - name: build-web+drive-examples
       env:
+        # Currently missing; see https://github.com/flutter/flutter/issues/81982
+        PLUGINS_TO_EXCLUDE_INTEGRATION_TESTS: "image_picker_for_web,shared_preferences_web,video_player_web"
         matrix:
           CHANNEL: "master"
           CHANNEL: "stable"
@@ -178,10 +180,10 @@ task:
         - ./chromedriver/chromedriver --port=4444 &
       build_script:
         - ./script/tool_runner.sh build-examples --web
-      test_script:
+      drive_script:
         # TODO(stuartmorgan): Eliminate this check once 2.1 reaches stable.
         - if [[ "$CHANNEL" == "master" ]]; then
-        -   ./script/tool_runner.sh drive-examples --web
+        -   ./script/tool_runner.sh drive-examples --web --exclude $PLUGINS_TO_EXCLUDE_INTEGRATION_TESTS
         - else
         -   echo "Requires null-safe integration_test; skipping."
         - fi
@@ -203,6 +205,9 @@ task:
       env:
         PATH: $PATH:/usr/local/bin
         PLUGINS_TO_SKIP_XCTESTS: "integration_test"
+        # in_app_purchase_ios is currently missing tests; see https://github.com/flutter/flutter/issues/81695
+        # sensor hangs on CI.
+        PLUGINS_TO_EXCLUDE_INTEGRATION_TESTS: "in_app_purchase_ios,sensors"
         matrix:
           PLUGIN_SHARDING: "--shardIndex 0 --shardCount 4"
           PLUGIN_SHARDING: "--shardIndex 1 --shardCount 4"
@@ -217,12 +222,13 @@ task:
         - xcrun simctl create Flutter-iPhone com.apple.CoreSimulator.SimDeviceType.iPhone-11 com.apple.CoreSimulator.SimRuntime.iOS-14-3 | xargs xcrun simctl boot
       build_script:
         - ./script/tool_runner.sh build-examples --ipa
-      test_script:
+      xctest_script:
         - ./script/tool_runner.sh xctest --skip $PLUGINS_TO_SKIP_XCTESTS --ios-destination "platform=iOS Simulator,name=iPhone 11,OS=latest"
+      drive_script:
         # `drive-examples` contains integration tests, which changes the UI of the application.
         # This UI change sometimes affects `xctest`.
         # So we run `drive-examples` after `xctest`, changing the order will result ci failure.
-        - ./script/tool_runner.sh drive-examples --ios
+        - ./script/tool_runner.sh drive-examples --ios --exclude $PLUGINS_TO_EXCLUDE_INTEGRATION_TESTS
     ### macOS desktop tasks ###
     - name: build_all_plugins_macos
       env:
@@ -241,7 +247,7 @@ task:
       build_script:
         - flutter config --enable-macos-desktop
         - ./script/tool_runner.sh build-examples --macos --no-ipa
-      test_script:
+      drive_script:
         - ./script/tool_runner.sh drive-examples --macos
 
 task:

packages/android_alarm_manager/example/test_driver/integration_test.dart

@@ -4,19 +4,6 @@
 
 // @dart=2.9
 
-import 'dart:async';
-import 'dart:convert';
-import 'dart:io';
+import 'package:integration_test/integration_test_driver.dart';
 
-import 'package:flutter_driver/flutter_driver.dart';
-
-Future<void> main() async {
-  final FlutterDriver driver = await FlutterDriver.connect();
-  final String data = await driver.requestData(
-    null,
-    timeout: const Duration(minutes: 1),
-  );
-  await driver.close();
-  final Map<String, dynamic> result = jsonDecode(data);
-  exit(result['result'] == 'true' ? 0 : 1);
-}
+Future<void> main() => integrationDriver();

packages/android_intent/example/test_driver/integration_test.dart

@@ -2,21 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.9
+// @dart=2.9
 
-import 'dart:async';
-import 'dart:convert';
-import 'dart:io';
+import 'package:integration_test/integration_test_driver.dart';
 
-import 'package:flutter_driver/flutter_driver.dart';
-
-Future<void> main() async {
-  final FlutterDriver driver = await FlutterDriver.connect();
-  final String data = await driver.requestData(
-    null,
-    timeout: const Duration(minutes: 1),
-  );
-  await driver.close();
-  final Map<String, dynamic> result = jsonDecode(data);
-  exit(result['result'] == 'true' ? 0 : 1);
-}
+Future<void> main() => integrationDriver();

…ttery/integration_test/battery_test.dart …ample/integration_test/battery_test.dartpackages/battery/battery/integration_test/battery_test.dart renamed to packages/battery/battery/example/integration_test/battery_test.dart packages/battery/battery/integration_test/battery_test.dart renamed to packages/battery/battery/example/integration_test/battery_test.dart

@@ -2,8 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.9
+// @dart=2.9
 
+import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:battery/battery.dart';
 import 'package:integration_test/integration_test.dart';
@@ -13,7 +14,18 @@ void main() {
 
   testWidgets('Can get battery level', (WidgetTester tester) async {
     final Battery battery = Battery();
-    final int batteryLevel = await battery.batteryLevel;
+    int batteryLevel;
+    try {
+      batteryLevel = await battery.batteryLevel;
+    } on PlatformException catch (e) {
+      // The "UNAVAIBLE" error just means that the system reported the battery
+      // level as unknown (e.g., the test is running on simulator); it still
+      // indicates that the plugin itself is working as expected, so consider it
+      // as passing.
+      if (e.code == 'UNAVAILABLE') {
+        batteryLevel = 1;
+      }
+    }
     expect(batteryLevel, isNotNull);
   });
 }

packages/battery/battery/example/test_driver/integration_test.dart

@@ -0,0 +1,9 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// @dart=2.9
+
+import 'package:integration_test/integration_test_driver.dart';
+
+Future<void> main() => integrationDriver();

…/integration_test/connectivity_test.dart …/integration_test/connectivity_test.dartpackages/connectivity/connectivity/example/test_driver/integration_test/connectivity_test.dart renamed to packages/connectivity/connectivity/example/integration_test/connectivity_test.dart packages/connectivity/connectivity/example/test_driver/integration_test/connectivity_test.dart renamed to packages/connectivity/connectivity/example/integration_test/connectivity_test.dart

@@ -0,0 +1,9 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// @dart=2.9
+
+import 'package:integration_test/integration_test_driver.dart';
+
+Future<void> main() => integrationDriver();

packages/connectivity/connectivity/example/test_driver/integration_test.dart

@@ -4,4 +4,4 @@
 
 import 'package:integration_test/integration_test_driver.dart';
 
-Future<void> main() async => integrationDriver();
+Future<void> main() => integrationDriver();