Adjust the dispatch queue of EDO reference release.

Make EDOHostService's references of local objects be released on its execution queue (if exists). Before this change, EDOHostService always releases its underlying objects in background queue, which may break user-side assumption that some objects should always be released on main thread.

In this case, user usually sends those objects to remote process through main thread's EDOHostService. So the host service should release the references on main thread as well.

PiperOrigin-RevId: 277129572

Author: AlbertWang0116

Service/Sources/EDOHostService.m

@@ -334,7 +334,11 @@ - (BOOL)isObjectAlive:(EDOObject *)object {
 
 - (BOOL)removeObjectWithAddress:(EDOPointerType)remoteAddress {
   NSNumber *edoKey = [NSNumber numberWithLongLong:remoteAddress];
+  __block NSObject *object NS_VALID_UNTIL_END_OF_SCOPE;
   dispatch_sync(_localObjectsSyncQueue, ^{
+    // Transfer the ownership of local object to the outer queue, where the object should be
+    // released.
+    object = self.localObjects[edoKey];
     [self.localObjects removeObjectForKey:edoKey];
   });
   return YES;
@@ -413,7 +417,14 @@ - (void)startReceivingRequestsForChannel:(id<EDOChannel>)channel {
           // needed for this request. The request handler will process this request
           // properly in its own queue.
           if ([request class] == [EDOObjectReleaseRequest class]) {
-            [EDOObjectReleaseRequest requestHandler](request, strongSelf);
+            dispatch_queue_t executionQueue = strongSelf.executionQueue;
+            if (executionQueue) {
+              dispatch_async(executionQueue, ^{
+                [EDOObjectReleaseRequest requestHandler](request, weakSelf);
+              });
+            } else {
+              [EDOObjectReleaseRequest requestHandler](request, strongSelf);
+            }
           } else {
             // Health check for the channel.
             [targetChannel sendData:EDOClientService.pingMessageData withCompletionHandler:nil];

Service/Tests/FunctionalTests/EDOServiceUITest.m

@@ -388,4 +388,33 @@ - (void)testPassByValueWithLocalObject {
   XCTAssertEqualObjects(localClassName, @"EDOObject");
 }
 
+/** Tests local object is released on the execution queue if it is released by EDOHostService. */
+- (void)testLocalObjectReleaseOnHostExecutionQueue {
+  [self launchApplicationWithPort:EDOTEST_APP_SERVICE_PORT initValue:5];
+  EDOHostService *service =
+      [EDOHostService serviceWithPort:2234
+                           rootObject:[[EDOTestDummyInTest alloc] initWithValue:9]
+                                queue:dispatch_get_main_queue()];
+  __block EDOTestDummyInTest *dummy = [[EDOTestDummyInTest alloc] init];
+  __weak EDOTestDummyInTest *weakDummy = dummy;
+  EDOTestDummy *remoteDummy = [EDOClientService rootObjectWithPort:EDOTEST_APP_SERVICE_PORT];
+
+  XCTestExpectation *expectation = [self expectationWithDescription:@"dummy is released on main."];
+  dummy.deallocHandlerBlock = ^{
+    XCTAssertTrue([NSThread isMainThread]);
+    [expectation fulfill];
+  };
+  dummy.block = ^{
+    dispatch_sync(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
+      dummy = nil;
+    });
+  };
+
+  [remoteDummy returnPlus10AndAsyncExecuteBlock:dummy];
+  [self waitForExpectations:@[ expectation ] timeout:2.0f];
+  XCTAssertNil(weakDummy);
+
+  [service invalidate];
+}
+
 @end

Service/Tests/FunctionalTests/EDOTestDummyInTest.h

@@ -25,6 +25,7 @@
 @property NSNumber *value;
 @property EDOTestDummyInTest *dummyInTest;
 @property void (^block)(void);
+@property(nullable) void (^deallocHandlerBlock)(void);
 
 - (instancetype)initWithValue:(int)value;
 

Service/Tests/FunctionalTests/EDOTestDummyInTest.m

@@ -39,6 +39,12 @@ - (instancetype)initWithValue:(int)value {
   return self;
 }
 
+- (void)dealloc {
+  if (_deallocHandlerBlock) {
+    _deallocHandlerBlock();
+  }
+}
+
 - (int)callTestDummy:(EDOTestDummy *)dummy {
   return self.value.intValue + [dummy returnIdWithInt:10].value + 3;
 }
@@ -59,4 +65,5 @@ - (void)invokeBlock {
     self.block();
   }
 }
+
 @end