[pigeon] Enable iOS Swift integration tests (#2858)

* [pigeon] Fix Java integration test script

Fixes a copy/paste error in run_tests.dart that would cause the command
for the new Java integration tests to run the Kotlin tests instead.

* Enable Swift iOS integration tests

packages/pigeon/platform_tests/test_plugin/ios/Classes/TestPlugin.swift

@@ -6,14 +6,30 @@ import Flutter
 import UIKit
 
 /**
- * This plugin is currently a no-op since only unit tests have been set up.
- * In the future, this will register Pigeon APIs used in integration tests.
+ * This plugin handles the native side of the integration tests in
+ * example/integration_test/.
  */
-public class TestPlugin: NSObject, FlutterPlugin {
+public class TestPlugin: NSObject, FlutterPlugin, AllVoidHostApi, HostEverything {
   public static func register(with registrar: FlutterPluginRegistrar) {
+    let plugin = TestPlugin()
+    AllVoidHostApiSetup.setUp(binaryMessenger: registrar.messenger(), api: plugin)
+    HostEverythingSetup.setUp(binaryMessenger: registrar.messenger(), api: plugin)
   }
 
-  public func handle(_ call: FlutterMethodCall, result: @escaping FlutterResult) {
-    result(FlutterMethodNotImplemented)
+  // MARK: AllVoidHostApi implementation
+
+  func doit() {
+    // No-op
+  }
+
+  // MARK: HostEverything implementation
+
+  func giveMeEverything() -> Everything {
+    // Currently unused in integration tests, so just return an empty object.
+    return Everything()
+  }
+
+  func echo(everything: Everything) -> Everything {
+    return everything
   }
 }

packages/pigeon/run_tests.sh

@@ -165,6 +165,10 @@ run_ios_swift_unittests() {
   dart run tool/run_tests.dart -t ios_swift_unittests --skip-generation
 }
 
+run_ios_swift_e2e_tests() {
+  dart run tool/run_tests.dart -t ios_swift_integration_tests --skip-generation
+}
+
 run_macos_swift_unittests() {
   dart run tool/run_tests.dart -t macos_swift_unittests --skip-generation
 }
@@ -214,7 +218,7 @@ run_ios_unittests() {
   popd
 }
 
-run_ios_e2e_tests() {
+run_ios_e2e_legacy_tests() {
   DARTLE_H="e2e_tests/test_objc/ios/Runner/dartle.h"
   DARTLE_M="e2e_tests/test_objc/ios/Runner/dartle.m"
   DARTLE_DART="e2e_tests/test_objc/lib/dartle.dart"
@@ -262,9 +266,13 @@ should_run_android_unittests=true
 should_run_dart_compilation_tests=true
 should_run_dart_unittests=true
 should_run_flutter_unittests=true
-should_run_ios_e2e_tests=true
+should_run_ios_e2e_legacy_tests=true
 should_run_ios_unittests=true
 should_run_ios_swift_unittests=true
+# Currently these are testing exactly the same thing as macos_swift_e2e_tests,
+# so we don't need to run both by default. This should become `true` if any
+# iOS-only tests are added (e.g., for a feature not supported by macOS).
+should_run_ios_swift_e2e_tests=false
 should_run_mock_handler_tests=true
 should_run_macos_swift_unittests=true
 should_run_macos_swift_e2e_tests=true
@@ -280,9 +288,10 @@ while getopts "t:l?h" opt; do
     should_run_dart_compilation_tests=false
     should_run_dart_unittests=false
     should_run_flutter_unittests=false
-    should_run_ios_e2e_tests=false
+    should_run_ios_e2e_legacy_tests=false
     should_run_ios_unittests=false
     should_run_ios_swift_unittests=false
+    should_run_ios_swift_e2e_tests=false
     should_run_mock_handler_tests=false
     should_run_macos_swift_unittests=false
     should_run_macos_swift_e2e_tests=false
@@ -296,10 +305,11 @@ while getopts "t:l?h" opt; do
     dart_compilation_tests) should_run_dart_compilation_tests=true ;;
     dart_unittests) should_run_dart_unittests=true ;;
     flutter_unittests) should_run_flutter_unittests=true ;;
-    ios_e2e_tests) should_run_ios_e2e_tests=true ;;
+    ios_e2e_legacy_tests) should_run_ios_e2e_legacy_tests=true ;;
     # TODO(stuartmorgan): Rename to include "objc".
     ios_unittests) should_run_ios_unittests=true ;;
     ios_swift_unittests) should_run_ios_swift_unittests=true ;;
+    ios_swift_e2e_tests) should_run_ios_swift_e2e_tests=true ;;
     mock_handler_tests) should_run_mock_handler_tests=true ;;
     macos_swift_unittests) should_run_macos_swift_unittests=true ;;
     macos_swift_e2e_tests) should_run_macos_swift_e2e_tests=true ;;
@@ -320,9 +330,10 @@ while getopts "t:l?h" opt; do
   dart_compilation_tests   - Compilation tests on generated Dart code.
   dart_unittests           - Unit tests on and analysis on Pigeon's implementation.
   flutter_unittests        - Unit tests on generated Dart code.
-  ios_e2e_tests            - End-to-end objc tests run on iOS Simulator
+  ios_e2e_legacy_tests     - Legacy end-to-end Obj-C tests; build-only.
   ios_unittests            - Unit tests on generated Objc code.
   ios_swift_unittests      - Unit tests on generated Swift code.
+  ios_swift_e2e_tests      - Integration tests on generated Swift code on iOS.
   mock_handler_tests       - Unit tests on generated Dart mock handler code.
   macos_swift_unittests    - Unit tests on generated Swift code on macOS.
   macos_swift_e2e_tests    - Integration tests on generated Swift code on macOS.
@@ -373,8 +384,11 @@ fi
 if [ "$should_run_ios_swift_unittests" = true ]; then
   run_ios_swift_unittests
 fi
-if [ "$should_run_ios_e2e_tests" = true ]; then
-  run_ios_e2e_tests
+if [ "$should_run_ios_swift_e2e_tests" = true ]; then
+  run_ios_swift_e2e_tests
+fi
+if [ "$should_run_ios_e2e_legacy_tests" = true ]; then
+  run_ios_e2e_legacy_tests
 fi
 if [ "$should_run_android_unittests" = true ]; then
   run_android_unittests

packages/pigeon/tool/run_tests.dart

@@ -68,11 +68,14 @@ const Map<String, _TestInfo> _tests = <String, _TestInfo>{
       function: _runFlutterUnitTests,
       description: 'Unit tests on generated Dart code.'),
   'ios_unittests': _TestInfo(
-      function: _runIosUnitTests,
+      function: _runIOSUnitTests,
       description: 'Unit tests on generated Objective-C code.'),
   'ios_swift_unittests': _TestInfo(
-      function: _runIosSwiftUnitTests,
+      function: _runIOSSwiftUnitTests,
       description: 'Unit tests on generated Swift code.'),
+  'ios_swift_integration_tests': _TestInfo(
+      function: _runIOSSwiftIntegrationTests,
+      description: 'Integration tests on generated Swift code.'),
   'macos_swift_unittests': _TestInfo(
       function: _runMacOSSwiftUnitTests,
       description: 'Unit tests on generated Swift code on macOS.'),
@@ -89,7 +92,8 @@ Future<int> _runAndroidJavaUnitTests() async {
 }
 
 Future<int> _runAndroidJavaIntegrationTests() async {
-  return _runAndroidIntegrationTests(_alternateLanguageTestPluginRelativePath);
+  return _runMobileIntegrationTests(
+      'Android', _alternateLanguageTestPluginRelativePath);
 }
 
 Future<int> _runAndroidKotlinUnitTests() async {
@@ -107,14 +111,15 @@ Future<int> _runAndroidKotlinUnitTests() async {
 }
 
 Future<int> _runAndroidKotlinIntegrationTests() async {
-  return _runAndroidIntegrationTests(_testPluginRelativePath);
+  return _runMobileIntegrationTests('Android', _testPluginRelativePath);
 }
 
-Future<int> _runAndroidIntegrationTests(String testPluginPath) async {
-  final String? device = await getDeviceForPlatform('android');
+Future<int> _runMobileIntegrationTests(
+    String platform, String testPluginPath) async {
+  final String? device = await getDeviceForPlatform(platform.toLowerCase());
   if (device == null) {
-    print('No Android device available. Attach an Android device or start '
-        'an emulator to run integration tests');
+    print('No $platform device available. Attach an $platform device or start '
+        'an emulator/simulator to run integration tests');
     return _noDeviceAvailableExitCode;
   }
 
@@ -218,7 +223,7 @@ Future<int> _runFlutterUnitTests() async {
   return 0;
 }
 
-Future<int> _runIosUnitTests() async {
+Future<int> _runIOSUnitTests() async {
   throw UnimplementedError('See run_tests.sh.');
 }
 
@@ -244,7 +249,7 @@ Future<int> _runMacOSSwiftIntegrationTests() async {
   );
 }
 
-Future<int> _runIosSwiftUnitTests() async {
+Future<int> _runIOSSwiftUnitTests() async {
   const String examplePath = './$_testPluginRelativePath/example';
   final int compileCode = await runFlutterBuild(
     examplePath,
@@ -263,6 +268,10 @@ Future<int> _runIosSwiftUnitTests() async {
   );
 }
 
+Future<int> _runIOSSwiftIntegrationTests() async {
+  return _runMobileIntegrationTests('iOS', _testPluginRelativePath);
+}
+
 Future<int> _runMockHandlerTests() async {
   const String unitTestsPath = './mock_handler_tester';
   final int generateCode = await runPigeon(