Implemented thread control for exported methods

Examples/UIExplorer/UIExplorerTests/UIExplorerTests.m

@@ -59,11 +59,10 @@
   return NO;
 }
 
-// Make sure this test runs first (underscores sort early) otherwise the
+// Make sure this test runs first because the other tests will tear out the rootView
-// other tests will tear out the rootView
+- (void)testAAA_RootViewLoadsAndRenders
-- (void)test__RootViewLoadsAndRenders
 {
-  UIViewController *vc = [[[[UIApplication sharedApplication] delegate] window] rootViewController];
+  UIViewController *vc = [UIApplication sharedApplication].delegate.window.rootViewController;
   RCTAssert([vc.view isKindOfClass:[RCTRootView class]], @"This test must run first.");
   NSDate *date = [NSDate dateWithTimeIntervalSinceNow:TIMEOUT_SECONDS];
   BOOL foundElement = NO;
@@ -72,10 +71,8 @@
   while ([date timeIntervalSinceNow] > 0 && !foundElement && !redboxError) {
     [[NSRunLoop mainRunLoop] runMode:NSDefaultRunLoopMode beforeDate:date];
     [[NSRunLoop mainRunLoop] runMode:NSRunLoopCommonModes beforeDate:date];
-
     redboxError = [[RCTRedBox sharedInstance] currentErrorMessage];
-
+    foundElement = [self findSubviewInView:vc.view matching:^(UIView *view) {
-    foundElement = [self findSubviewInView:vc.view matching:^BOOL(UIView *view) {
       if ([view respondsToSelector:@selector(attributedText)]) {
         NSString *text = [(id)view attributedText].string;
         if ([text isEqualToString:@"<View>"]) {
@@ -120,6 +117,7 @@
   [_runner runTest:_cmd module:@"TabBarExample"];
 }
 
+// Make sure this test runs last
 - (void)testZZZ_NotInRecordMode
 {
   RCTAssert(_runner.recordMode == NO, @"Don't forget to turn record mode back to NO before commit.");

Libraries/ActionSheetIOS/RCTActionSheetManager.m

@@ -34,92 +34,88 @@ RCT_EXPORT_METHOD(showActionSheetWithOptions:(NSDictionary *)options
                   failureCallback:(RCTResponseSenderBlock)failureCallback
                   successCallback:(RCTResponseSenderBlock)successCallback)
 {
-  dispatch_async(dispatch_get_main_queue(), ^{
+  UIActionSheet *actionSheet = [[UIActionSheet alloc] init];
-    UIActionSheet *actionSheet = [[UIActionSheet alloc] init];
 
-    actionSheet.title = options[@"title"];
+  actionSheet.title = options[@"title"];
 
-    for (NSString *option in options[@"options"]) {
+  for (NSString *option in options[@"options"]) {
-      [actionSheet addButtonWithTitle:option];
+    [actionSheet addButtonWithTitle:option];
-    }
+  }
 
-    if (options[@"destructiveButtonIndex"]) {
+  if (options[@"destructiveButtonIndex"]) {
-      actionSheet.destructiveButtonIndex = [options[@"destructiveButtonIndex"] integerValue];
+    actionSheet.destructiveButtonIndex = [options[@"destructiveButtonIndex"] integerValue];
-    }
+  }
-    if (options[@"cancelButtonIndex"]) {
+  if (options[@"cancelButtonIndex"]) {
-      actionSheet.cancelButtonIndex = [options[@"cancelButtonIndex"] integerValue];
+    actionSheet.cancelButtonIndex = [options[@"cancelButtonIndex"] integerValue];
-    }
+  }
 
-    actionSheet.delegate = self;
+  actionSheet.delegate = self;
 
-    _callbacks[keyForInstance(actionSheet)] = successCallback;
+  _callbacks[RCTKeyForInstance(actionSheet)] = successCallback;
 
-    UIWindow *appWindow = [[[UIApplication sharedApplication] delegate] window];
+  UIWindow *appWindow = [[[UIApplication sharedApplication] delegate] window];
-    if (appWindow == nil) {
+  if (appWindow == nil) {
-      RCTLogError(@"Tried to display action sheet but there is no application window. options: %@", options);
+    RCTLogError(@"Tried to display action sheet but there is no application window. options: %@", options);
-      return;
+    return;
-    }
+  }
-    [actionSheet showInView:appWindow];
+  [actionSheet showInView:appWindow];
-  });
 }
 
 RCT_EXPORT_METHOD(showShareActionSheetWithOptions:(NSDictionary *)options
                   failureCallback:(RCTResponseSenderBlock)failureCallback
                   successCallback:(RCTResponseSenderBlock)successCallback)
 {
-  dispatch_async(dispatch_get_main_queue(), ^{
+  NSMutableArray *items = [NSMutableArray array];
-    NSMutableArray *items = [NSMutableArray array];
+  id message = options[@"message"];
-    id message = options[@"message"];
+  id url = options[@"url"];
-    id url = options[@"url"];
+  if ([message isKindOfClass:[NSString class]]) {
-    if ([message isKindOfClass:[NSString class]]) {
+    [items addObject:message];
-      [items addObject:message];
+  }
-    }
+  if ([url isKindOfClass:[NSString class]]) {
-    if ([url isKindOfClass:[NSString class]]) {
+    [items addObject:[NSURL URLWithString:url]];
-      [items addObject:[NSURL URLWithString:url]];
+  }
-    }
+  if ([items count] == 0) {
-    if ([items count] == 0) {
+    failureCallback(@[@"No `url` or `message` to share"]);
-      failureCallback(@[@"No `url` or `message` to share"]);
+    return;
-      return;
+  }
-    }
+  UIActivityViewController *share = [[UIActivityViewController alloc] initWithActivityItems:items applicationActivities:nil];
-    UIActivityViewController *share = [[UIActivityViewController alloc] initWithActivityItems:items applicationActivities:nil];
+  UIViewController *ctrl = [[[[UIApplication sharedApplication] delegate] window] rootViewController];
-    UIViewController *ctrl = [[[[UIApplication sharedApplication] delegate] window] rootViewController];
+  if ([share respondsToSelector:@selector(setCompletionWithItemsHandler:)]) {
-    if ([share respondsToSelector:@selector(setCompletionWithItemsHandler:)]) {
+    share.completionWithItemsHandler = ^(NSString *activityType, BOOL completed, NSArray *returnedItems, NSError *activityError) {
-      share.completionWithItemsHandler = ^(NSString *activityType, BOOL completed, NSArray *returnedItems, NSError *activityError) {
+      if (activityError) {
-        if (activityError) {
+        failureCallback(@[[activityError localizedDescription]]);
-          failureCallback(@[[activityError localizedDescription]]);
+      } else {
-        } else {
+        successCallback(@[@(completed), (activityType ?: [NSNull null])]);
-          successCallback(@[@(completed), (activityType ?: [NSNull null])]);
+      }
-        }
+    };
-      };
+  } else {
-    } else {
 
 #if __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_8_0
 
-      if (![UIActivityViewController instancesRespondToSelector:@selector(completionWithItemsHandler)]) {
+    if (![UIActivityViewController instancesRespondToSelector:@selector(completionWithItemsHandler)]) {
-        // Legacy iOS 7 implementation
+      // Legacy iOS 7 implementation
-        share.completionHandler = ^(NSString *activityType, BOOL completed) {
+      share.completionHandler = ^(NSString *activityType, BOOL completed) {
-          successCallback(@[@(completed), (activityType ?: [NSNull null])]);
+        successCallback(@[@(completed), (activityType ?: [NSNull null])]);
-        };
+      };
-      } else
+    } else
 
 #endif
 
-      {
+    {
-        // iOS 8 version
+      // iOS 8 version
-        share.completionWithItemsHandler = ^(NSString *activityType, BOOL completed, NSArray *returnedItems, NSError *activityError) {
+      share.completionWithItemsHandler = ^(NSString *activityType, BOOL completed, NSArray *returnedItems, NSError *activityError) {
-          successCallback(@[@(completed), (activityType ?: [NSNull null])]);
+        successCallback(@[@(completed), (activityType ?: [NSNull null])]);
-        };
+      };
-      }
     }
-    [ctrl presentViewController:share animated:YES completion:nil];
+  }
-  });
+  [ctrl presentViewController:share animated:YES completion:nil];
 }
 
 #pragma mark UIActionSheetDelegate Methods
 
 - (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex
 {
-  NSString *key = keyForInstance(actionSheet);
+  NSString *key = RCTKeyForInstance(actionSheet);
   RCTResponseSenderBlock callback = _callbacks[key];
   if (callback) {
     callback(@[@(buttonIndex)]);
@@ -133,7 +129,7 @@ RCT_EXPORT_METHOD(showShareActionSheetWithOptions:(NSDictionary *)options
 
 #pragma mark Private
 
-NS_INLINE NSString *keyForInstance(id instance)
+static NSString *RCTKeyForInstance(id instance)
 {
   return [NSString stringWithFormat:@"%p", instance];
 }

Libraries/Animation/RCTAnimationExperimentalManager.m

@@ -68,6 +68,11 @@ RCT_EXPORT_MODULE()
   return self;
 }
 
+- (dispatch_queue_t)methodQueue
+{
+  return _bridge.uiManager.methodQueue;
+}
+
 - (id (^)(CGFloat))interpolateFrom:(CGFloat[])fromArray to:(CGFloat[])toArray count:(NSUInteger)count typeName:(const char *)typeName
 {
   if (count == 1) {

Libraries/Geolocation/RCTLocationObserver.m

@@ -33,7 +33,9 @@ typedef struct {
   CLLocationAccuracy accuracy;
 } RCTLocationOptions;
 
-static RCTLocationOptions RCTLocationOptionsWithJSON(id json)
+@implementation RCTConvert (RCTLocationOptions)
+
++ (RCTLocationOptions)RCTLocationOptions:(id)json
 {
   NSDictionary *options = [RCTConvert NSDictionary:json];
   return (RCTLocationOptions){
@@ -43,6 +45,8 @@ static RCTLocationOptions RCTLocationOptionsWithJSON(id json)
   };
 }
 
+@end
+
 static NSDictionary *RCTPositionError(RCTPositionErrorCode code, NSString *msg /* nil for default */)
 {
   if (!msg) {
@@ -121,6 +125,7 @@ RCT_EXPORT_MODULE()
 - (void)dealloc
 {
   [_locationManager stopUpdatingLocation];
+  _locationManager.delegate = nil;
 }
 
 #pragma mark - Private API
@@ -153,41 +158,33 @@ RCT_EXPORT_MODULE()
 
 #pragma mark - Public API
 
-RCT_EXPORT_METHOD(startObserving:(NSDictionary *)optionsJSON)
+RCT_EXPORT_METHOD(startObserving:(RCTLocationOptions)options)
 {
   [self checkLocationConfig];
 
-  dispatch_async(dispatch_get_main_queue(), ^{
+  // Select best options
+  _observerOptions = options;
+  for (RCTLocationRequest *request in _pendingRequests) {
+    _observerOptions.accuracy = MIN(_observerOptions.accuracy, request.options.accuracy);
+  }
 
-    // Select best options
+  _locationManager.desiredAccuracy = _observerOptions.accuracy;
-    _observerOptions = RCTLocationOptionsWithJSON(optionsJSON);
+  [self beginLocationUpdates];
-    for (RCTLocationRequest *request in _pendingRequests) {
+  _observingLocation = YES;
-      _observerOptions.accuracy = MIN(_observerOptions.accuracy, request.options.accuracy);
-    }
-
-    _locationManager.desiredAccuracy = _observerOptions.accuracy;
-    [self beginLocationUpdates];
-    _observingLocation = YES;
-
-  });
 }
 
 RCT_EXPORT_METHOD(stopObserving)
 {
-  dispatch_async(dispatch_get_main_queue(), ^{
+  // Stop observing
+  _observingLocation = NO;
 
-    // Stop observing
+  // Stop updating if no pending requests
-    _observingLocation = NO;
+  if (_pendingRequests.count == 0) {
-
+    [_locationManager stopUpdatingLocation];
-    // Stop updating if no pending requests
+  }
-    if (_pendingRequests.count == 0) {
-      [_locationManager stopUpdatingLocation];
-    }
-
-  });
 }
 
-RCT_EXPORT_METHOD(getCurrentPosition:(NSDictionary *)optionsJSON
+RCT_EXPORT_METHOD(getCurrentPosition:(RCTLocationOptions)options
                   withSuccessCallback:(RCTResponseSenderBlock)successBlock
                   errorCallback:(RCTResponseSenderBlock)errorBlock)
 {
@@ -198,56 +195,49 @@ RCT_EXPORT_METHOD(getCurrentPosition:(NSDictionary *)optionsJSON
     return;
   }
 
-  dispatch_async(dispatch_get_main_queue(), ^{
+  if (![CLLocationManager locationServicesEnabled]) {
-
+    if (errorBlock) {
-    if (![CLLocationManager locationServicesEnabled]) {
+      errorBlock(@[
-      if (errorBlock) {
+        RCTPositionError(RCTPositionErrorUnavailable, @"Location services disabled.")
-        errorBlock(@[
+      ]);
-          RCTPositionError(RCTPositionErrorUnavailable, @"Location services disabled.")
-        ]);
-        return;
-      }
-    }
-
-    if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusDenied) {
-      if (errorBlock) {
-        errorBlock(@[
-          RCTPositionError(RCTPositionErrorDenied, nil)
-        ]);
-        return;
-      }
-    }
-
-    // Get options
-    RCTLocationOptions options = RCTLocationOptionsWithJSON(optionsJSON);
-
-    // Check if previous recorded location exists and is good enough
-    if (_lastLocationEvent &&
-        CFAbsoluteTimeGetCurrent() - [RCTConvert NSTimeInterval:_lastLocationEvent[@"timestamp"]] < options.maximumAge &&
-        [_lastLocationEvent[@"coords"][@"accuracy"] doubleValue] >= options.accuracy) {
-
-      // Call success block with most recent known location
-      successBlock(@[_lastLocationEvent]);
       return;
     }
+  }
 
-    // Create request
+  if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusDenied) {
-    RCTLocationRequest *request = [[RCTLocationRequest alloc] init];
+    if (errorBlock) {
-    request.successBlock = successBlock;
+      errorBlock(@[
-    request.errorBlock = errorBlock ?: ^(NSArray *args){};
+        RCTPositionError(RCTPositionErrorDenied, nil)
-    request.options = options;
+      ]);
-    request.timeoutTimer = [NSTimer scheduledTimerWithTimeInterval:options.timeout
+      return;
-                                                            target:self
+    }
-                                                          selector:@selector(timeout:)
+  }
-                                                          userInfo:request
-                                                           repeats:NO];
-    [_pendingRequests addObject:request];
 
-    // Configure location manager and begin updating location
+  // Check if previous recorded location exists and is good enough
-    _locationManager.desiredAccuracy = MIN(_locationManager.desiredAccuracy, options.accuracy);
+  if (_lastLocationEvent &&
-    [self beginLocationUpdates];
+      CFAbsoluteTimeGetCurrent() - [RCTConvert NSTimeInterval:_lastLocationEvent[@"timestamp"]] < options.maximumAge &&
+      [_lastLocationEvent[@"coords"][@"accuracy"] doubleValue] >= options.accuracy) {
 
-  });
+    // Call success block with most recent known location
+    successBlock(@[_lastLocationEvent]);
+    return;
+  }
+
+  // Create request
+  RCTLocationRequest *request = [[RCTLocationRequest alloc] init];
+  request.successBlock = successBlock;
+  request.errorBlock = errorBlock ?: ^(NSArray *args){};
+  request.options = options;
+  request.timeoutTimer = [NSTimer scheduledTimerWithTimeInterval:options.timeout
+                                                          target:self
+                                                        selector:@selector(timeout:)
+                                                        userInfo:request
+                                                         repeats:NO];
+  [_pendingRequests addObject:request];
+
+  // Configure location manager and begin updating location
+  _locationManager.desiredAccuracy = MIN(_locationManager.desiredAccuracy, options.accuracy);
+  [self beginLocationUpdates];
 }
 
 #pragma mark - CLLocationManagerDelegate

Libraries/LinkingIOS/RCTLinkingManager.m

@@ -62,8 +62,10 @@ RCT_EXPORT_METHOD(openURL:(NSURL *)URL)
 RCT_EXPORT_METHOD(canOpenURL:(NSURL *)URL
                   callback:(RCTResponseSenderBlock)callback)
 {
-  BOOL canOpen = [[UIApplication sharedApplication] canOpenURL:URL];
+  dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
-  callback(@[@(canOpen)]);
+    BOOL canOpen = [[UIApplication sharedApplication] canOpenURL:URL];
+    callback(@[@(canOpen)]);
+  });
 }
 
 - (NSDictionary *)constantsToExport

Libraries/RCTTest/RCTTestModule.h

@@ -15,14 +15,24 @@
 
 @interface RCTTestModule : NSObject <RCTBridgeModule>
 
-// This is typically polled while running the runloop until true
+/**
-@property (nonatomic, readonly, getter=isDone) BOOL done;
+ * The snapshot test controller for this module.
-
+ */
-// This is used to give meaningful names to snapshot image files.
+@property (nonatomic, weak) FBSnapshotTestController *controller;
-@property (nonatomic, assign) SEL testSelector;
 
+/**
+ * This is the view to be snapshotted.
+ */
 @property (nonatomic, weak) UIView *view;
 
-- (instancetype)initWithSnapshotController:(FBSnapshotTestController *)controller view:(UIView *)view;
+/**
+ * This is used to give meaningful names to snapshot image files.
+ */
+@property (nonatomic, assign) SEL testSelector;
+
+/**
+ * This is typically polled while running the runloop until true.
+ */
+@property (nonatomic, readonly, getter=isDone) BOOL done;
 
 @end

Libraries/RCTTest/RCTTestModule.m

@@ -12,21 +12,25 @@
 #import "FBSnapshotTestController.h"
 #import "RCTAssert.h"
 #import "RCTLog.h"
+#import "RCTUIManager.h"
 
 @implementation RCTTestModule
 {
-  __weak FBSnapshotTestController *_snapshotController;
-  __weak UIView *_view;
   NSMutableDictionary *_snapshotCounter;
 }
 
+@synthesize bridge = _bridge;
+
 RCT_EXPORT_MODULE()
 
-- (instancetype)initWithSnapshotController:(FBSnapshotTestController *)controller view:(UIView *)view
+- (dispatch_queue_t)methodQueue
+{
+  return _bridge.uiManager.methodQueue;
+}
+
+- (instancetype)init
 {
   if ((self = [super init])) {
-    _snapshotController = controller;
-    _view = view;
     _snapshotCounter = [NSMutableDictionary new];
   }
   return self;
@@ -34,30 +38,29 @@ RCT_EXPORT_MODULE()
 
 RCT_EXPORT_METHOD(verifySnapshot:(RCTResponseSenderBlock)callback)
 {
-  if (!_snapshotController) {
+  RCTAssert(_controller != nil, @"No snapshot controller configured.");
-    RCTLogWarn(@"No snapshot controller configured.");
+
-    callback(@[]);
+  [_bridge.uiManager addUIBlock:^(RCTUIManager *uiManager, RCTSparseArray *viewRegistry) {
-    return;
-  }
 
-  dispatch_async(dispatch_get_main_queue(), ^{
     NSString *testName = NSStringFromSelector(_testSelector);
-    _snapshotCounter[testName] = @([_snapshotCounter[testName] integerValue] + 1);
+    _snapshotCounter[testName] = [@([_snapshotCounter[testName] integerValue] + 1) stringValue];
+
     NSError *error = nil;
-    BOOL success = [_snapshotController compareSnapshotOfView:_view
+    BOOL success = [_controller compareSnapshotOfView:_view
-                                                     selector:_testSelector
+                                             selector:_testSelector
-                                                   identifier:[_snapshotCounter[testName] stringValue]
+                                           identifier:_snapshotCounter[testName]
-                                                        error:&error];
+                                                error:&error];
+
     RCTAssert(success, @"Snapshot comparison failed: %@", error);
     callback(@[]);
-  });
+  }];
 }
 
 RCT_EXPORT_METHOD(markTestCompleted)
 {
-  dispatch_async(dispatch_get_main_queue(), ^{
+  [_bridge.uiManager addUIBlock:^(RCTUIManager *uiManager, RCTSparseArray *viewRegistry) {
     _done = YES;
-  });
+  }];
 }
 
 @end

Libraries/RCTTest/RCTTestRunner.m

@@ -19,7 +19,7 @@
 
 @implementation RCTTestRunner
 {
-  FBSnapshotTestController *_snapshotController;
+  FBSnapshotTestController *_testController;
 }
 
 - (instancetype)initWithApp:(NSString *)app referenceDir:(NSString *)referenceDir
@@ -27,8 +27,8 @@
   if ((self = [super init])) {
     NSString *sanitizedAppName = [app stringByReplacingOccurrencesOfString:@"/" withString:@"-"];
     sanitizedAppName = [sanitizedAppName stringByReplacingOccurrencesOfString:@"\\" withString:@"-"];
-    _snapshotController = [[FBSnapshotTestController alloc] initWithTestName:sanitizedAppName];
+    _testController = [[FBSnapshotTestController alloc] initWithTestName:sanitizedAppName];
-    _snapshotController.referenceImagesDirectory = referenceDir;
+    _testController.referenceImagesDirectory = referenceDir;
     _scriptURL = [NSURL URLWithString:[NSString stringWithFormat:@"http://localhost:8081/%@.includeRequire.runModule.bundle?dev=true", app]];
   }
   return self;
@@ -36,12 +36,12 @@
 
 - (void)setRecordMode:(BOOL)recordMode
 {
-  _snapshotController.recordMode = recordMode;
+  _testController.recordMode = recordMode;
 }
 
 - (BOOL)recordMode
 {
-  return _snapshotController.recordMode;
+  return _testController.recordMode;
 }
 
 - (void)runTest:(SEL)test module:(NSString *)moduleName
@@ -59,27 +59,22 @@
 
 - (void)runTest:(SEL)test module:(NSString *)moduleName initialProps:(NSDictionary *)initialProps expectErrorBlock:(BOOL(^)(NSString *error))expectErrorBlock
 {
-  UIViewController *vc = [[[[UIApplication sharedApplication] delegate] window] rootViewController];
+  RCTRootView *rootView = [[RCTRootView alloc] initWithBundleURL:_scriptURL
-  if ([vc.view isKindOfClass:[RCTRootView class]]) {
+                                                      moduleName:moduleName
-    [(RCTRootView *)vc.view invalidate]; // Make sure the normal app view doesn't interfere
+                                                   launchOptions:nil];
-  }
-  vc.view = [[UIView alloc] init];
-
-  RCTTestModule *testModule = [[RCTTestModule alloc] initWithSnapshotController:_snapshotController view:nil];
-  testModule.testSelector = test;
-  RCTBridge *bridge = [[RCTBridge alloc] initWithBundleURL:_scriptURL
-                                            moduleProvider:^(){
-                                              return @[testModule];
-                                            }
-                                             launchOptions:nil];
-
-  RCTRootView *rootView = [[RCTRootView alloc] initWithBridge:bridge
-                                                   moduleName:moduleName];
-  testModule.view = rootView;
-  [vc.view addSubview:rootView]; // Add as subview so it doesn't get resized
   rootView.initialProperties = initialProps;
   rootView.frame = CGRectMake(0, 0, 320, 2000); // Constant size for testing on multiple devices
 
+  NSString *testModuleName = RCTBridgeModuleNameForClass([RCTTestModule class]);
+  RCTTestModule *testModule = rootView.bridge.modules[testModuleName];
+  testModule.controller = _testController;
+  testModule.testSelector = test;
+  testModule.view = rootView;
+
+  UIViewController *vc = [UIApplication sharedApplication].delegate.window.rootViewController;
+  vc.view = [[UIView alloc] init];
+  [vc.view addSubview:rootView]; // Add as subview so it doesn't get resized
+
   NSDate *date = [NSDate dateWithTimeIntervalSinceNow:TIMEOUT_SECONDS];
   NSString *error = [[RCTRedBox sharedInstance] currentErrorMessage];
   while ([date timeIntervalSinceNow] > 0 && ![testModule isDone] && error == nil) {

React/Base/RCTBridge.h

@@ -101,13 +101,6 @@ static const char *__rct_import_##module##_##method##__ = #module"."#method;
  */
 @property (nonatomic, copy, readonly) NSDictionary *modules;
 
-/**
- * The shadow queue is used to execute callbacks from the JavaScript code. All
- * native hooks (e.g. exported module methods) will be executed on the shadow
- * queue.
- */
-@property (nonatomic, readonly) dispatch_queue_t shadowQueue;
-
 /**
  * The launch options that were used to initialize the bridge.
  */

React/Base/RCTBridge.m

@@ -792,6 +792,7 @@ static NSDictionary *RCTLocalModulesConfig()
 @implementation RCTBridge
 {
   RCTSparseArray *_modulesByID;
+  RCTSparseArray *_queuesByID;
   NSDictionary *_modulesByName;
   id<RCTJavaScriptExecutor> _javaScriptExecutor;
   Class _executorClass;
@@ -824,13 +825,13 @@ static id<RCTJavaScriptExecutor> _latestJSExecutor;
 
   return self;
 }
+
 - (void)setUp
 {
   Class executorClass = _executorClass ?: _globalExecutorClass ?: [RCTContextExecutor class];
   _javaScriptExecutor = [[executorClass alloc] init];
   _latestJSExecutor = _javaScriptExecutor;
   _eventDispatcher = [[RCTEventDispatcher alloc] initWithBridge:self];
-  _shadowQueue = dispatch_queue_create("com.facebook.React.ShadowQueue", DISPATCH_QUEUE_SERIAL);
   _displayLink = [[RCTDisplayLink alloc] initWithBridge:self];
   _frameUpdateObservers = [[NSMutableSet alloc] init];
   _scheduledCalls = [[NSMutableArray alloc] init];
@@ -848,21 +849,29 @@ static id<RCTJavaScriptExecutor> _latestJSExecutor;
   [RCTBridgeModuleClassesByModuleID() enumerateObjectsUsingBlock:^(Class moduleClass, NSUInteger moduleID, BOOL *stop) {
     NSString *moduleName = RCTModuleNamesByID[moduleID];
     // Check if module instance has already been registered for this name
-    if ((_modulesByID[moduleID] = modulesByName[moduleName])) {
+    id<RCTBridgeModule> module = modulesByName[moduleName];
+    if (module) {
       // Preregistered instances takes precedence, no questions asked
       if (!preregisteredModules[moduleName]) {
         // It's OK to have a name collision as long as the second instance is nil
         RCTAssert([[moduleClass alloc] init] == nil,
-                  @"Attempted to register RCTBridgeModule class %@ for the name '%@', \
+                  @"Attempted to register RCTBridgeModule class %@ for the name "
-                  but name was already registered by class %@", moduleClass,
+                  "'%@', but name was already registered by class %@", moduleClass,
                   moduleName, [modulesByName[moduleName] class]);
       }
+      if ([module class] != moduleClass) {
+        RCTLogInfo(@"RCTBridgeModule of class %@ with name '%@' was encountered "
+                   "in the project, but name was already registered by class %@."
+                   "That's fine if it's intentional - just letting you know.",
+                   moduleClass, moduleName, [modulesByName[moduleName] class]);
+      }
     } else {
       // Module name hasn't been used before, so go ahead and instantiate
-      id<RCTBridgeModule> module = [[moduleClass alloc] init];
+      module = [[moduleClass alloc] init];
-      if (module) {
+    }
-        _modulesByID[moduleID] = modulesByName[moduleName] = module;
+    if (module) {
-      }
+      // Store module instance
+      _modulesByID[moduleID] = modulesByName[moduleName] = module;
     }
   }];
 
@@ -876,6 +885,14 @@ static id<RCTJavaScriptExecutor> _latestJSExecutor;
     }
   }
 
+  // Get method queue
+  _queuesByID = [[RCTSparseArray alloc] init];
+  [_modulesByID enumerateObjectsUsingBlock:^(id<RCTBridgeModule> module, NSNumber *moduleID, BOOL *stop) {
+    if ([module respondsToSelector:@selector(methodQueue)]) {
+      _queuesByID[moduleID] = [module methodQueue] ?: dispatch_get_main_queue();
+    }
+  }];
+
   // Inject module data into JS context
   NSString *configJSON = RCTJSONStringify(@{
     @"remoteModuleConfig": RCTRemoteModulesConfig(_modulesByName),
@@ -1027,6 +1044,7 @@ static id<RCTJavaScriptExecutor> _latestJSExecutor;
 
   // Release modules (breaks retain cycle if module has strong bridge reference)
   _modulesByID = nil;
+  _queuesByID = nil;
   _modulesByName = nil;
 }
 
@@ -1203,6 +1221,8 @@ static id<RCTJavaScriptExecutor> _latestJSExecutor;
     return;
   }
 
+  // TODO: if we sort the requests by module, we could dispatch once per
+  // module instead of per request, which would reduce the call overhead.
   for (NSUInteger i = 0; i < numRequests; i++) {
     @autoreleasepool {
       [self _handleRequestNumber:i
@@ -1212,14 +1232,15 @@ static id<RCTJavaScriptExecutor> _latestJSExecutor;
     }
   }
 
-  // TODO: only used by RCTUIManager - can we eliminate this special case?
+  // TODO: batchDidComplete is only used by RCTUIManager - can we eliminate this special case?
-  dispatch_async(self.shadowQueue, ^{
+  [_modulesByID enumerateObjectsUsingBlock:^(id<RCTBridgeModule> module, NSNumber *moduleID, BOOL *stop) {
-    for (id module in _modulesByID.allObjects) {
+    if ([module respondsToSelector:@selector(batchDidComplete)]) {
-      if ([module respondsToSelector:@selector(batchDidComplete)]) {
+      dispatch_queue_t queue = _queuesByID[moduleID];
+      dispatch_async(queue ?: dispatch_get_main_queue(), ^{
         [module batchDidComplete];
-      }
+      });
     }
-  });
+  }];
 }
 
 - (BOOL)_handleRequestNumber:(NSUInteger)i
@@ -1241,7 +1262,8 @@ static id<RCTJavaScriptExecutor> _latestJSExecutor;
   RCTModuleMethod *method = methods[methodID];
 
   __weak RCTBridge *weakSelf = self;
-  dispatch_async(self.shadowQueue, ^{
+  dispatch_queue_t queue = _queuesByID[moduleID];
+  dispatch_async(queue ?: dispatch_get_main_queue(), ^{
     __strong RCTBridge *strongSelf = weakSelf;
 
     if (!strongSelf.isValid) {

React/Base/RCTBridgeModule.h

@@ -89,6 +89,23 @@ typedef void (^RCTResponseSenderBlock)(NSArray *response);
   __attribute__((__aligned__(1))) \
   static const char *__rct_export_entry__[] = { __func__, #js_name, NULL }
 
+/**
+ * The queue that will be used to call all exported methods. If omitted, this
+ * will default the main queue, which is recommended for any methods that
+ * interact with UIKit. If your methods perform heavy work such as filesystem
+ * or network access, you should return a custom serial queue. Example:
+ *
+ * - (dispatch_queue_t)methodQueue
+ * {
+ *   return dispatch_queue_create("com.mydomain.FileQueue", DISPATCH_QUEUE_SERIAL);
+ * }
+ *
+ * Alternatively, if only some methods on the module should be executed on a
+ * background queue you can leave this method unimplemented, and simply
+ * dispatch_async() within the method itself.
+ */
+- (dispatch_queue_t)methodQueue;
+
 /**
  * Injects constants into JS. These constants are made accessible via
  * NativeModules.ModuleName.X. This method is called when the module is

React/Base/RCTConvert.h

@@ -138,7 +138,7 @@ BOOL RCTCopyProperty(id target, id source, NSString *keyPath);
 /**
  * Underlying implementation of RCT_ENUM_CONVERTER macro. Ignore this.
  */
-NSNumber *RCTConverterEnumValue(const char *, NSDictionary *, NSNumber *, id);
+NSNumber *RCTConvertEnumValue(const char *, NSDictionary *, NSNumber *, id);
 
 #ifdef __cplusplus
 }
@@ -190,7 +190,7 @@ RCT_CUSTOM_CONVERTER(type, type, [[self NSNumber:json] getter])
   dispatch_once(&onceToken, ^{                            \
     mapping = values;                                     \
   });                                                     \
-  NSNumber *converted = RCTConverterEnumValue(#type, mapping, @(default), json); \
+  NSNumber *converted = RCTConvertEnumValue(#type, mapping, @(default), json); \
   return ((type(*)(id, SEL))objc_msgSend)(converted, @selector(getter)); \
 }
 

React/Base/RCTConvert.m

@@ -58,6 +58,10 @@ RCT_CONVERTER(NSString *, NSString, description)
 
 + (NSURL *)NSURL:(id)json
 {
+  if (!json || json == (id)kCFNull) {
+    return nil;
+  }
+
   if (![json isKindOfClass:[NSString class]]) {
     RCTLogError(@"Expected NSString for NSURL, received %@: %@", [json classForCoder], json);
     return nil;
@@ -115,7 +119,7 @@ RCT_CUSTOM_CONVERTER(NSTimeInterval, NSTimeInterval, [self double:json] / 1000.0
 // JS standard for time zones is minutes.
 RCT_CUSTOM_CONVERTER(NSTimeZone *, NSTimeZone, [NSTimeZone timeZoneForSecondsFromGMT:[self double:json] * 60.0])
 
-NSNumber *RCTConverterEnumValue(const char *typeName, NSDictionary *mapping, NSNumber *defaultValue, id json)
+NSNumber *RCTConvertEnumValue(const char *typeName, NSDictionary *mapping, NSNumber *defaultValue, id json)
 {
   if (!json || json == (id)kCFNull) {
     return defaultValue;

React/Modules/RCTAlertManager.m

@@ -64,37 +64,34 @@ RCT_EXPORT_METHOD(alertWithArgs:(NSDictionary *)args
     return;
   }
 
-  dispatch_async(dispatch_get_main_queue(), ^{
+  UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:title
+                                                      message:message
+                                                     delegate:self
+                                            cancelButtonTitle:nil
+                                            otherButtonTitles:nil];
 
-    UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:title
+  NSMutableArray *buttonKeys = [[NSMutableArray alloc] initWithCapacity:buttons.count];
-                                                        message:message
-                                                       delegate:self
-                                              cancelButtonTitle:nil
-                                              otherButtonTitles:nil];
 
-    NSMutableArray *buttonKeys = [[NSMutableArray alloc] initWithCapacity:buttons.count];
+  NSInteger index = 0;
-
+  for (NSDictionary *button in buttons) {
-    NSInteger index = 0;
+    if (button.count != 1) {
-    for (NSDictionary *button in buttons) {
+      RCTLogError(@"Button definitions should have exactly one key.");
-      if (button.count != 1) {
-        RCTLogError(@"Button definitions should have exactly one key.");
-      }
-      NSString *buttonKey = [button.allKeys firstObject];
-      NSString *buttonTitle = [button[buttonKey] description];
-      [alertView addButtonWithTitle:buttonTitle];
-      if ([buttonKey isEqualToString: @"cancel"]) {
-        alertView.cancelButtonIndex = index;
-      }
-      [buttonKeys addObject:buttonKey];
-      index ++;
     }
+    NSString *buttonKey = [button.allKeys firstObject];
+    NSString *buttonTitle = [button[buttonKey] description];
+    [alertView addButtonWithTitle:buttonTitle];
+    if ([buttonKey isEqualToString: @"cancel"]) {
+      alertView.cancelButtonIndex = index;
+    }
+    [buttonKeys addObject:buttonKey];
+    index ++;
+  }
 
-    [_alerts addObject:alertView];
+  [_alerts addObject:alertView];
-    [_alertCallbacks addObject:callback ?: ^(id unused) {}];
+  [_alertCallbacks addObject:callback ?: ^(id unused) {}];
-    [_alertButtonKeys addObject:buttonKeys];
+  [_alertButtonKeys addObject:buttonKeys];
 
-    [alertView show];
+  [alertView show];
-  });
 }
 
 #pragma mark - UIAlertViewDelegate

React/Modules/RCTAsyncLocalStorage.m

@@ -61,20 +61,6 @@ static id RCTReadFile(NSString *filePath, NSString *key, NSDictionary **errorOut
   return nil;
 }
 
-static dispatch_queue_t RCTFileQueue(void)
-{
-  static dispatch_queue_t fileQueue = NULL;
-  static dispatch_once_t onceToken;
-  dispatch_once(&onceToken, ^{
-    // All JS is single threaded, so a serial queue is our only option.
-    fileQueue = dispatch_queue_create("com.facebook.rkFile", DISPATCH_QUEUE_SERIAL);
-    dispatch_set_target_queue(fileQueue,
-                              dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0));
-  });
-
-  return fileQueue;
-}
-
 #pragma mark - RCTAsyncLocalStorage
 
 @implementation RCTAsyncLocalStorage
@@ -90,6 +76,11 @@ static dispatch_queue_t RCTFileQueue(void)
 
 RCT_EXPORT_MODULE()
 
+- (dispatch_queue_t)methodQueue
+{
+  return dispatch_queue_create("com.facebook.React.AsyncLocalStorageQueue", DISPATCH_QUEUE_SERIAL);
+}
+
 - (NSString *)_filePathForKey:(NSString *)key
 {
   NSString *safeFileName = RCTMD5Hash(key);
@@ -196,99 +187,89 @@ RCT_EXPORT_METHOD(multiGet:(NSArray *)keys
     return;
   }
 
-  dispatch_async(RCTFileQueue(), ^{
+  id errorOut = [self _ensureSetup];
-    id errorOut = [self _ensureSetup];
+  if (errorOut) {
-    if (errorOut) {
+    callback(@[@[errorOut], [NSNull null]]);
-      callback(@[@[errorOut], [NSNull null]]);
+    return;
-      return;
+  }
-    }
+  NSMutableArray *errors;
-    NSMutableArray *errors;
+  NSMutableArray *result = [[NSMutableArray alloc] initWithCapacity:keys.count];
-    NSMutableArray *result = [[NSMutableArray alloc] initWithCapacity:keys.count];
+  for (NSString *key in keys) {
-    for (NSString *key in keys) {
+    id keyError = [self _appendItemForKey:key toArray:result];
-      id keyError = [self _appendItemForKey:key toArray:result];
+    RCTAppendError(keyError, &errors);
-      RCTAppendError(keyError, &errors);
+  }
-    }
+  [self _writeManifest:&errors];
-    [self _writeManifest:&errors];
+  callback(@[errors ?: [NSNull null], result]);
-    callback(@[errors ?: [NSNull null], result]);
-  });
 }
 
 RCT_EXPORT_METHOD(multiSet:(NSArray *)kvPairs
                   callback:(RCTResponseSenderBlock)callback)
 {
-  dispatch_async(RCTFileQueue(), ^{
+  id errorOut = [self _ensureSetup];
-    id errorOut = [self _ensureSetup];
+  if (errorOut) {
-    if (errorOut) {
+    callback(@[@[errorOut]]);
-      callback(@[@[errorOut]]);
+    return;
-      return;
+  }
-    }
+  NSMutableArray *errors;
-    NSMutableArray *errors;
+  for (NSArray *entry in kvPairs) {
-    for (NSArray *entry in kvPairs) {
+    id keyError = [self _writeEntry:entry];
-      id keyError = [self _writeEntry:entry];
+    RCTAppendError(keyError, &errors);
-      RCTAppendError(keyError, &errors);
+  }
-    }
+  [self _writeManifest:&errors];
-    [self _writeManifest:&errors];
+  if (callback) {
-    if (callback) {
+    callback(@[errors ?: [NSNull null]]);
-      callback(@[errors ?: [NSNull null]]);
+  }
-    }
-  });
 }
 
 RCT_EXPORT_METHOD(multiRemove:(NSArray *)keys
                   callback:(RCTResponseSenderBlock)callback)
 {
-  dispatch_async(RCTFileQueue(), ^{
+  id errorOut = [self _ensureSetup];
-    id errorOut = [self _ensureSetup];
+  if (errorOut) {
-    if (errorOut) {
+    callback(@[@[errorOut]]);
-      callback(@[@[errorOut]]);
+    return;
-      return;
+  }
+  NSMutableArray *errors;
+  for (NSString *key in keys) {
+    id keyError = RCTErrorForKey(key);
+    if (!keyError) {
+      NSString *filePath = [self _filePathForKey:key];
+      [[NSFileManager defaultManager] removeItemAtPath:filePath error:nil];
+      [_manifest removeObjectForKey:key];
     }
-    NSMutableArray *errors;
+    RCTAppendError(keyError, &errors);
-    for (NSString *key in keys) {
+  }
-      id keyError = RCTErrorForKey(key);
+  [self _writeManifest:&errors];
-      if (!keyError) {
+  if (callback) {
-        NSString *filePath = [self _filePathForKey:key];
+    callback(@[errors ?: [NSNull null]]);
-        [[NSFileManager defaultManager] removeItemAtPath:filePath error:nil];
+  }
-        [_manifest removeObjectForKey:key];
-      }
-      RCTAppendError(keyError, &errors);
-    }
-    [self _writeManifest:&errors];
-    if (callback) {
-      callback(@[errors ?: [NSNull null]]);
-    }
-  });
 }
 
 RCT_EXPORT_METHOD(clear:(RCTResponseSenderBlock)callback)
 {
-  dispatch_async(RCTFileQueue(), ^{
+  id errorOut = [self _ensureSetup];
-    id errorOut = [self _ensureSetup];
+  if (!errorOut) {
-    if (!errorOut) {
+    NSError *error;
-      NSError *error;
+    for (NSString *key in _manifest) {
-      for (NSString *key in _manifest) {
+      NSString *filePath = [self _filePathForKey:key];
-        NSString *filePath = [self _filePathForKey:key];
+      [[NSFileManager defaultManager] removeItemAtPath:filePath error:&error];
-        [[NSFileManager defaultManager] removeItemAtPath:filePath error:&error];
-      }
-      [_manifest removeAllObjects];
-      errorOut = [self _writeManifest:nil];
     }
-    if (callback) {
+    [_manifest removeAllObjects];
-      callback(@[errorOut ?: [NSNull null]]);
+    errorOut = [self _writeManifest:nil];
-    }
+  }
-  });
+  if (callback) {
+    callback(@[errorOut ?: [NSNull null]]);
+  }
 }
 
 RCT_EXPORT_METHOD(getAllKeys:(RCTResponseSenderBlock)callback)
 {
-  dispatch_async(RCTFileQueue(), ^{
+  id errorOut = [self _ensureSetup];
-    id errorOut = [self _ensureSetup];
+  if (errorOut) {
-    if (errorOut) {
+    callback(@[errorOut, [NSNull null]]);
-      callback(@[errorOut, [NSNull null]]);
+  } else {
-    } else {
+    callback(@[[NSNull null], [_manifest allKeys]]);
-      callback(@[[NSNull null], [_manifest allKeys]]);
+  }
-    }
-  });
 }
 
 @end

React/Modules/RCTExceptionsManager.m

@@ -48,13 +48,11 @@ RCT_EXPORT_METHOD(reportUnhandledException:(NSString *)message
   }
 
 #ifdef DEBUG
-    [[RCTRedBox sharedInstance] showErrorMessage:message withStack:stack];
+  [[RCTRedBox sharedInstance] showErrorMessage:message withStack:stack];
 #else
   if (RCTReloadRetries < _maxReloadAttempts) {
     RCTReloadRetries++;
-    dispatch_async(dispatch_get_main_queue(), ^{
+    [[NSNotificationCenter defaultCenter] postNotificationName:RCTReloadNotification object:nil];
-      [[NSNotificationCenter defaultCenter] postNotificationName:RCTReloadNotification object:nil];
-    });
   } else {
     NSError *error;
     const NSUInteger MAX_SANITIZED_LENGTH = 75;

React/Modules/RCTSourceCode.m

@@ -24,7 +24,6 @@ RCT_EXPORT_METHOD(getScriptText:(RCTResponseSenderBlock)successCallback
   } else {
     failureCallback(@[RCTMakeError(@"Source code is not available", nil, nil)]);
   }
-
 }
 
 @end

React/Modules/RCTStatusBarManager.m

@@ -29,31 +29,25 @@ RCT_EXPORT_MODULE()
 RCT_EXPORT_METHOD(setStyle:(UIStatusBarStyle)statusBarStyle
                   animated:(BOOL)animated)
 {
-  dispatch_async(dispatch_get_main_queue(), ^{
+  if (RCTViewControllerBasedStatusBarAppearance()) {
-
+    RCTLogError(@"RCTStatusBarManager module requires that the \
-    if (RCTViewControllerBasedStatusBarAppearance()) {
+                UIViewControllerBasedStatusBarAppearance key in the Info.plist is set to NO");
-      RCTLogError(@"RCTStatusBarManager module requires that the \
+  } else {
-                  UIViewControllerBasedStatusBarAppearance key in the Info.plist is set to NO");
+    [[UIApplication sharedApplication] setStatusBarStyle:statusBarStyle
-    } else {
+                                                animated:animated];
-      [[UIApplication sharedApplication] setStatusBarStyle:statusBarStyle
+  }
-                                                  animated:animated];
-    }
-  });
 }
 
 RCT_EXPORT_METHOD(setHidden:(BOOL)hidden
                   withAnimation:(UIStatusBarAnimation)animation)
 {
-  dispatch_async(dispatch_get_main_queue(), ^{
+  if (RCTViewControllerBasedStatusBarAppearance()) {
-
+    RCTLogError(@"RCTStatusBarManager module requires that the \
-    if (RCTViewControllerBasedStatusBarAppearance()) {
+                UIViewControllerBasedStatusBarAppearance key in the Info.plist is set to NO");
-      RCTLogError(@"RCTStatusBarManager module requires that the \
+  } else {
-                  UIViewControllerBasedStatusBarAppearance key in the Info.plist is set to NO");
+    [[UIApplication sharedApplication] setStatusBarHidden:hidden
-    } else {
+                                            withAnimation:animation];
-      [[UIApplication sharedApplication] setStatusBarHidden:hidden
+  }
-                                              withAnimation:animation];
-    }
-  });
 }
 
 - (NSDictionary *)constantsToExport

React/Modules/RCTTiming.m

@@ -187,21 +187,17 @@ RCT_EXPORT_METHOD(createTimer:(NSNumber *)callbackID
                                                 interval:jsDuration
                                               targetTime:targetTime
                                                  repeats:repeats];
-  dispatch_async(dispatch_get_main_queue(), ^{
+  _timers[callbackID] = timer;
-    _timers[callbackID] = timer;
+  [self startTimers];
-    [self startTimers];
-  });
 }
 
 RCT_EXPORT_METHOD(deleteTimer:(NSNumber *)timerID)
 {
   if (timerID) {
-    dispatch_async(dispatch_get_main_queue(), ^{
+    _timers[timerID] = nil;
-      _timers[timerID] = nil;
+    if (_timers.count == 0) {
-      if (_timers.count == 0) {
+      [self stopTimers];
-        [self stopTimers];
+    }
-      }
-    });
   } else {
     RCTLogWarn(@"Called deleteTimer: with a nil timerID");
   }

React/Modules/RCTUIManager.m

@@ -178,7 +178,7 @@ static UIViewAnimationCurve UIViewAnimationCurveFromRCTAnimationType(RCTAnimatio
 
 @implementation RCTUIManager
 {
-  __weak dispatch_queue_t _shadowQueue;
+  dispatch_queue_t _shadowQueue;
 
   // Root views are only mutated on the shadow queue
   NSMutableSet *_rootViewTags;
@@ -242,24 +242,12 @@ static NSDictionary *RCTViewConfigForModule(Class managerClass, NSString *viewNa
   };
 }
 
-/**
- * This private constructor should only be called when creating
- * isolated UIImanager instances for testing. Normal initialization
- * is via -init:, which is called automatically by the bridge.
- */
-- (instancetype)initWithShadowQueue:(dispatch_queue_t)shadowQueue
-{
-  if ((self = [self init])) {
-    _shadowQueue = shadowQueue;
-    _viewManagers = [[NSMutableDictionary alloc] init];
-  }
-  return self;
-}
-
 - (instancetype)init
 {
   if ((self = [super init])) {
 
+    _shadowQueue = dispatch_queue_create("com.facebook.React.ShadowQueue", DISPATCH_QUEUE_SERIAL);
+
     _pendingUIBlocksLock = [[NSLock alloc] init];
 
     _defaultShadowViews = [[NSMutableDictionary alloc] init];
@@ -310,7 +298,6 @@ static NSDictionary *RCTViewConfigForModule(Class managerClass, NSString *viewNa
   RCTAssert(_bridge == nil, @"Should not re-use same UIIManager instance");
 
   _bridge = bridge;
-  _shadowQueue = _bridge.shadowQueue;
   _shadowViewRegistry = [[RCTSparseArray alloc] init];
 
   // Get view managers from bridge
@@ -328,6 +315,11 @@ static NSDictionary *RCTViewConfigForModule(Class managerClass, NSString *viewNa
   _viewConfigs = [viewConfigs copy];
 }
 
+- (dispatch_queue_t)methodQueue
+{
+  return _shadowQueue;
+}
+
 - (void)registerRootView:(UIView *)rootView;
 {
   RCTAssertMainThread();
@@ -366,7 +358,7 @@ static NSDictionary *RCTViewConfigForModule(Class managerClass, NSString *viewNa
   NSNumber *reactTag = rootView.reactTag;
   RCTAssert(RCTIsReactRootView(reactTag), @"Specified view %@ is not a root view", reactTag);
 
-  dispatch_async(_bridge.shadowQueue, ^{
+  dispatch_async(_shadowQueue, ^{
     RCTShadowView *rootShadowView = _shadowViewRegistry[reactTag];
     RCTAssert(rootShadowView != nil, @"Could not locate root view with tag #%@", reactTag);
     rootShadowView.frame = frame;
@@ -396,8 +388,6 @@ static NSDictionary *RCTViewConfigForModule(Class managerClass, NSString *viewNa
 
 - (void)addUIBlock:(RCTViewManagerUIBlock)block
 {
-  RCTAssert(![NSThread isMainThread], @"This method should only be called on the shadow thread");
-
   if (!self.isValid) {
     return;
   }
@@ -417,7 +407,7 @@ static NSDictionary *RCTViewConfigForModule(Class managerClass, NSString *viewNa
 
 - (RCTViewManagerUIBlock)uiBlockWithLayoutUpdateForRootView:(RCTShadowView *)rootShadowView
 {
-  RCTAssert(![NSThread isMainThread], @"This should never be executed on main thread.");
+  RCTAssert(![NSThread isMainThread], @"Should be called on shadow thread");
 
   NSMutableSet *viewsWithNewFrames = [NSMutableSet setWithCapacity:1];
 
@@ -679,6 +669,8 @@ RCT_EXPORT_METHOD(manageChildren:(NSNumber *)containerReactTag
 
   [self _purgeChildren:permanentlyRemovedChildren fromRegistry:registry];
 
+  // TODO (#5906496): optimize all these loops - constantly calling array.count is not efficient
+
   // Figure out what to insert - merge temporary inserts and adds
   NSMutableDictionary *destinationsToChildrenToAdd = [NSMutableDictionary dictionary];
   for (NSInteger index = 0, length = temporarilyRemovedChildren.count; index < length; index++) {
@@ -886,8 +878,6 @@ RCT_EXPORT_METHOD(blur:(NSNumber *)reactTag)
 
 - (void)flushUIBlocks
 {
-  RCTAssert(![NSThread isMainThread], @"Should be called on shadow thread");
-
   // First copy the previous blocks into a temporary variable, then reset the
   // pending blocks to a new array. This guards against mutation while
   // processing the pending blocks in another thread.

React/Views/RCTViewManager.h

@@ -109,8 +109,7 @@ typedef void (^RCTViewManagerUIBlock)(RCTUIManager *uiManager, RCTSparseArray *v
  * within the view or shadowView.
  */
 #define RCT_REMAP_VIEW_PROPERTY(name, keyPath, type)                           \
-RCT_EXPORT_VIEW_PROP_CONFIG(name, type)                                        \
+RCT_CUSTOM_VIEW_PROPERTY(name, type, UIView) {                                 \
-- (void)set_##name:(id)json forView:(id)view withDefaultView:(id)defaultView { \
   if ((json && !RCTSetProperty(view, @#keyPath, @selector(type:), json)) ||    \
       (!json && !RCTCopyProperty(view, defaultView, @#keyPath))) {             \
     RCTLogError(@"%@ does not have setter for `%s` property", [view class], #name); \
@@ -118,8 +117,7 @@ RCT_EXPORT_VIEW_PROP_CONFIG(name, type)                                        \
 }
 
 #define RCT_REMAP_SHADOW_PROPERTY(name, keyPath, type)                         \
-RCT_EXPORT_SHADOW_PROP_CONFIG(name, type)                                      \
+RCT_CUSTOM_SHADOW_PROPERTY(name, type, RCTShadowView) {                        \
-- (void)set_##name:(id)json forShadowView:(id)view withDefaultView:(id)defaultView { \
   if ((json && !RCTSetProperty(view, @#keyPath, @selector(type:), json)) ||    \
       (!json && !RCTCopyProperty(view, defaultView, @#keyPath))) {             \
     RCTLogError(@"%@ does not have setter for `%s` property", [view class], #name); \
@@ -132,11 +130,11 @@ RCT_EXPORT_SHADOW_PROP_CONFIG(name, type)                                      \
  * refer to "json", "view" and "defaultView" to implement the required logic.
  */
 #define RCT_CUSTOM_VIEW_PROPERTY(name, type, viewClass) \
-RCT_EXPORT_VIEW_PROP_CONFIG(name, type)                 \
++ (NSDictionary *)getPropConfigView_##name { return @{@"name": @#name, @"type": @#type}; } \
 - (void)set_##name:(id)json forView:(viewClass *)view withDefaultView:(viewClass *)defaultView
 
 #define RCT_CUSTOM_SHADOW_PROPERTY(name, type, viewClass) \
-RCT_EXPORT_SHADOW_PROP_CONFIG(name, type)                 \
++ (NSDictionary *)getPropConfigShadow_##name { return @{@"name": @#name, @"type": @#type}; } \
 - (void)set_##name:(id)json forShadowView:(viewClass *)view withDefaultView:(viewClass *)defaultView
 
 /**
@@ -164,17 +162,4 @@ RCT_EXPORT_SHADOW_PROP_CONFIG(name, type)                 \
   [self set_##newName:json forView:view withDefaultView:defaultView]; \
 }
 
-/**
- * PROP_CONFIG macros should only be paired with property setters.
- */
-#define RCT_EXPORT_VIEW_PROP_CONFIG(name, type) \
-+ (NSDictionary *)getPropConfigView_##name {   \
-  return @{@"name": @#name, @"type": @#type};  \
-}
-
-#define RCT_EXPORT_SHADOW_PROP_CONFIG(name, type) \
-+ (NSDictionary *)getPropConfigShadow_##name {   \
-  return @{@"name": @#name, @"type": @#type};    \
-}
-
 @end

React/Views/RCTViewManager.m

@@ -14,6 +14,7 @@
 #import "RCTEventDispatcher.h"
 #import "RCTLog.h"
 #import "RCTShadowView.h"
+#import "RCTUIManager.h"
 #import "RCTUtils.h"
 #import "RCTView.h"
 
@@ -23,6 +24,11 @@
 
 RCT_EXPORT_MODULE()
 
+- (dispatch_queue_t)methodQueue
+{
+  return [_bridge.uiManager methodQueue];
+}
+
 - (UIView *)view
 {
   return [[RCTView alloc] init];