[Darwin] Move FlutterBinaryMessengerRelay to common (flutter#44395)

Migrates FlutterBinaryMessengerRelay to
//flutter/shell/platform/darwin/common so that it can be used in a
followup patch on macOS, to fix a memory leak due to a retain cycle.

Migrates the unit tests to be compatible with gtest, which is used by
the darwin/common unit tests.

Issue: flutter#116445


## Pre-launch Checklist

- [X] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [X] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [X] I read and followed the [Flutter Style Guide] and the [C++,
Objective-C, Java style guides].
- [X] I listed at least one issue that this PR fixes in the description
above.
- [X] I added new tests to check the change I am making or feature I am
adding, or Hixie said the PR is test-exempt. See [testing the engine]
for instructions on writing and running engine tests.
- [X] I updated/added relevant documentation (doc comments with `///`).
- [X] I signed the [CLA].
- [X] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

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Author: cbracken

ci/licenses_golden/licenses_flutter

@@ -2567,6 +2567,9 @@ ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Headers/FlutterC
 ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Headers/FlutterDartProject.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Headers/FlutterMacros.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Headers/FlutterTexture.h + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.h + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.mm + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelayTest.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterChannels.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterChannelsTest.m + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterCodecs.mm + ../../../flutter/LICENSE
@@ -2576,6 +2579,8 @@ ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterSt
 ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterStandardCodecHelper.cc + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterStandardCodecHelper.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterStandardCodec_Internal.h + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterTestUtils.h + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterTestUtils.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/graphics/FlutterDarwinContextMetalImpeller.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/graphics/FlutterDarwinContextMetalImpeller.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/graphics/FlutterDarwinContextMetalSkia.h + ../../../flutter/LICENSE
@@ -2595,9 +2600,6 @@ ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Headers/FlutterView
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterAppDelegate.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterAppDelegateTest.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterAppDelegate_Test.h + ../../../flutter/LICENSE
-ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.h + ../../../flutter/LICENSE
-ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.mm + ../../../flutter/LICENSE
-ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelayTest.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterCallbackCache.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterCallbackCache_Internal.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterChannelKeyResponder.h + ../../../flutter/LICENSE
@@ -5296,6 +5298,9 @@ FILE: ../../../flutter/shell/platform/darwin/common/framework/Headers/FlutterCod
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Headers/FlutterDartProject.h
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Headers/FlutterMacros.h
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Headers/FlutterTexture.h
+FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.h
+FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.mm
+FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelayTest.mm
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterChannels.mm
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterChannelsTest.m
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterCodecs.mm
@@ -5305,6 +5310,8 @@ FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterStan
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterStandardCodecHelper.cc
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterStandardCodecHelper.h
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterStandardCodec_Internal.h
+FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterTestUtils.h
+FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterTestUtils.mm
 FILE: ../../../flutter/shell/platform/darwin/graphics/FlutterDarwinContextMetalImpeller.h
 FILE: ../../../flutter/shell/platform/darwin/graphics/FlutterDarwinContextMetalImpeller.mm
 FILE: ../../../flutter/shell/platform/darwin/graphics/FlutterDarwinContextMetalSkia.h
@@ -5325,9 +5332,6 @@ FILE: ../../../flutter/shell/platform/darwin/ios/framework/Info.plist
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterAppDelegate.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterAppDelegateTest.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterAppDelegate_Test.h
-FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.h
-FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.mm
-FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelayTest.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterCallbackCache.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterCallbackCache_Internal.h
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterChannelKeyResponder.h

shell/platform/darwin/common/BUILD.gn

@@ -37,6 +37,7 @@ source_set("framework_common") {
   cflags_objcc = flutter_cflags_objcc_arc
 
   sources = [
+    "framework/Source/FlutterBinaryMessengerRelay.mm",
     "framework/Source/FlutterChannels.mm",
     "framework/Source/FlutterCodecs.mm",
     "framework/Source/FlutterNSBundleUtils.h",
@@ -69,6 +70,8 @@ executable("framework_common_unittests") {
   testonly = true
 
   sources = [
+    "framework/Source/FlutterBinaryMessengerRelayTest.mm",
+    "framework/Source/FlutterTestUtils.mm",
     "framework/Source/flutter_codecs_unittest.mm",
     "framework/Source/flutter_standard_codec_unittest.mm",
   ]
@@ -82,6 +85,7 @@ executable("framework_common_unittests") {
     ":framework_common_fixtures",
     "//flutter/testing",
     "//third_party/dart/runtime:libdart_jit",
+    "//third_party/ocmock:ocmock",
   ]
 
   public_configs = [ "//flutter:config" ]

…ork/Source/FlutterBinaryMessengerRelay.h …ork/Source/FlutterBinaryMessengerRelay.hshell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.h renamed to shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.h shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.h renamed to shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.h

@@ -2,6 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#ifndef SHELL_PLATFORM_DARWIN_COMMON_FRAMEWORK_SOURCE_FLUTTERBINARYMESSENGERRELAY_H_
+#define SHELL_PLATFORM_DARWIN_COMMON_FRAMEWORK_SOURCE_FLUTTERBINARYMESSENGERRELAY_H_
+
 #import "flutter/shell/platform/darwin/common/framework/Headers/FlutterBinaryMessenger.h"
 #import "flutter/shell/platform/darwin/common/framework/Headers/FlutterMacros.h"
 
@@ -12,3 +15,5 @@ FLUTTER_DARWIN_EXPORT
 @property(nonatomic, assign) NSObject<FlutterBinaryMessenger>* parent;
 - (instancetype)initWithParent:(NSObject<FlutterBinaryMessenger>*)parent;
 @end
+
+#endif  // SHELL_PLATFORM_DARWIN_COMMON_FRAMEWORK_SOURCE_FLUTTERBINARYMESSENGERRELAY_H_

…rk/Source/FlutterBinaryMessengerRelay.mm …rk/Source/FlutterBinaryMessengerRelay.mmshell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.mm renamed to shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.mm shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.mm renamed to shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.mm

@@ -2,10 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#import "flutter/shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.h"
+#import "flutter/shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.h"
 
 #include "flutter/fml/logging.h"
 
+FLUTTER_ASSERT_ARC
+
 @implementation FlutterBinaryMessengerRelay
 #pragma mark - FlutterBinaryMessenger
 

…ource/FlutterBinaryMessengerRelayTest.mm …ource/FlutterBinaryMessengerRelayTest.mmshell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelayTest.mm renamed to shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelayTest.mm shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelayTest.mm renamed to shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelayTest.mm

@@ -2,35 +2,31 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#import "flutter/shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.h"
+#import "flutter/shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.h"
 
 #import <OCMock/OCMock.h>
-#import <XCTest/XCTest.h>
 
 #import "flutter/shell/platform/darwin/common/framework/Headers/FlutterMacros.h"
+#import "flutter/shell/platform/darwin/common/framework/Source/FlutterTestUtils.h"
+#import "flutter/testing/testing.h"
+#include "gtest/gtest.h"
 
 FLUTTER_ASSERT_ARC
 
 @protocol FlutterTaskQueue <NSObject>
 @end
 
-@interface FlutterBinaryMessengerRelayTest : XCTestCase
+@interface FlutterBinaryMessengerRelayTest : NSObject
 @end
 
 @implementation FlutterBinaryMessengerRelayTest
 
-- (void)setUp {
-}
-
-- (void)tearDown {
-}
-
 - (void)testCreate {
   id messenger = OCMProtocolMock(@protocol(FlutterBinaryMessenger));
   FlutterBinaryMessengerRelay* relay =
       [[FlutterBinaryMessengerRelay alloc] initWithParent:messenger];
-  XCTAssertNotNil(relay);
-  XCTAssertEqual(messenger, relay.parent);
+  EXPECT_NE(relay, nil);
+  EXPECT_EQ(messenger, relay.parent);
 }
 
 - (void)testPassesCallOn {
@@ -78,3 +74,33 @@ - (void)testMakeBackgroundTaskQueue {
 }
 
 @end
+
+TEST(FlutterBinaryMessengerRelayTest, Create) {
+  ASSERT_FALSE(FLTThrowsObjcException(^{
+    [[FlutterBinaryMessengerRelayTest alloc] testCreate];
+  }));
+}
+
+TEST(FlutterBinaryMessengerRelayTest, PassesCallOn) {
+  ASSERT_FALSE(FLTThrowsObjcException(^{
+    [[FlutterBinaryMessengerRelayTest alloc] testPassesCallOn];
+  }));
+}
+
+TEST(FlutterBinaryMessengerRelayTest, DoesntPassCallOn) {
+  ASSERT_FALSE(FLTThrowsObjcException(^{
+    [[FlutterBinaryMessengerRelayTest alloc] testDoesntPassCallOn];
+  }));
+}
+
+TEST(FlutterBinaryMessengerRelayTest, SetMessageHandlerWithTaskQueue) {
+  ASSERT_FALSE(FLTThrowsObjcException(^{
+    [[FlutterBinaryMessengerRelayTest alloc] testSetMessageHandlerWithTaskQueue];
+  }));
+}
+
+TEST(FlutterBinaryMessengerRelayTest, SetMakeBackgroundTaskQueue) {
+  ASSERT_FALSE(FLTThrowsObjcException(^{
+    [[FlutterBinaryMessengerRelayTest alloc] testMakeBackgroundTaskQueue];
+  }));
+}

shell/platform/darwin/common/framework/Source/FlutterTestUtils.h

@@ -0,0 +1,13 @@
+// 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.
+
+#ifndef SHELL_PLATFORM_DARWIN_COMMON_FRAMEWORK_SOURCE_FLUTTERTESTUTILS_H_
+#define SHELL_PLATFORM_DARWIN_COMMON_FRAMEWORK_SOURCE_FLUTTERTESTUTILS_H_
+
+#import <Foundation/Foundation.h>
+
+/// Returns YES if the block throws an exception.
+BOOL FLTThrowsObjcException(dispatch_block_t block);
+
+#endif  // SHELL_PLATFORM_DARWIN_COMMON_FRAMEWORK_SOURCE_FLUTTERTESTUTILS_H_

shell/platform/darwin/common/framework/Source/FlutterTestUtils.mm

@@ -0,0 +1,18 @@
+// 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.
+
+#import "flutter/shell/platform/darwin/common/framework/Source/FlutterTestUtils.h"
+
+#import "flutter/shell/platform/darwin/common/framework/Headers/FlutterMacros.h"
+
+FLUTTER_ASSERT_ARC
+
+BOOL FLTThrowsObjcException(dispatch_block_t block) {
+  @try {
+    block();
+  } @catch (...) {
+    return YES;
+  }
+  return NO;
+}

shell/platform/darwin/ios/BUILD.gn

@@ -75,7 +75,6 @@ source_set("flutter_framework_source") {
 
   sources = [
     "framework/Source/FlutterAppDelegate.mm",
-    "framework/Source/FlutterBinaryMessengerRelay.mm",
     "framework/Source/FlutterCallbackCache.mm",
     "framework/Source/FlutterCallbackCache_Internal.h",
     "framework/Source/FlutterChannelKeyResponder.h",
@@ -283,7 +282,6 @@ shared_library("ios_test_flutter") {
   ]
   sources = [
     "framework/Source/FlutterAppDelegateTest.mm",
-    "framework/Source/FlutterBinaryMessengerRelayTest.mm",
     "framework/Source/FlutterChannelKeyResponderTest.mm",
     "framework/Source/FlutterDartProjectTest.mm",
     "framework/Source/FlutterEmbedderKeyResponderTest.mm",

shell/platform/darwin/ios/framework/Source/FlutterEngine.mm

@@ -19,7 +19,7 @@
 #include "flutter/shell/common/thread_host.h"
 #include "flutter/shell/common/variable_refresh_rate_display.h"
 #import "flutter/shell/platform/darwin/common/command_line.h"
-#import "flutter/shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.h"
+#import "flutter/shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.h"
 #import "flutter/shell/platform/darwin/ios/framework/Source/FlutterDartProject_Internal.h"
 #import "flutter/shell/platform/darwin/ios/framework/Source/FlutterDartVMServicePublisher.h"
 #import "flutter/shell/platform/darwin/ios/framework/Source/FlutterIndirectScribbleDelegate.h"

shell/platform/darwin/ios/framework/Source/FlutterEngineTest.mm

@@ -11,7 +11,7 @@
 #import "flutter/common/settings.h"
 #include "flutter/fml/synchronization/sync_switch.h"
 #import "flutter/shell/platform/darwin/common/framework/Headers/FlutterMacros.h"
-#import "flutter/shell/platform/darwin/ios/framework/Source/FlutterBinaryMessengerRelay.h"
+#import "flutter/shell/platform/darwin/common/framework/Source/FlutterBinaryMessengerRelay.h"
 #import "flutter/shell/platform/darwin/ios/framework/Source/FlutterDartProject_Internal.h"
 #import "flutter/shell/platform/darwin/ios/framework/Source/FlutterEngine_Test.h"
 #import "flutter/shell/platform/darwin/ios/framework/Source/FlutterTextInputPlugin.h"