Added unit tests for module init

Summary: The module initialization process is complex and full of race conditions. This diff adds a set of unit tests that verify that modules setup happens in the correct order, and enforces all the various conditions for main/background init.

Reviewed By: javache

Differential Revision: D2994145

fb-gh-sync-id: 92ea84508cdeeb280ff0fb9e9b2dffa8dbc37e66
shipit-source-id: 92ea84508cdeeb280ff0fb9e9b2dffa8dbc37e66

Examples/UIExplorer/UIExplorerUnitTests/RCTModuleInitNotificationRaceTests.m

@@ -0,0 +1,142 @@
+/**
+ * The examples provided by Facebook are for non-commercial testing and
+ * evaluation purposes only.
+ *
+ * Facebook reserves all rights not expressly granted.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON INFRINGEMENT. IN NO EVENT SHALL
+ * FACEBOOK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#import <Foundation/Foundation.h>
+#import <XCTest/XCTest.h>
+
+#import "RCTBridge.h"
+#import "RCTBridge+Private.h"
+#import "RCTBridgeModule.h"
+#import "RCTUtils.h"
+#import "RCTUIManager.h"
+#import "RCTViewManager.h"
+
+#define RUN_RUNLOOP_WHILE(CONDITION) \
+{ \
+  NSDate *timeout = [NSDate dateWithTimeIntervalSinceNow:5]; \
+  while ((CONDITION)) { \
+    [[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:[NSDate dateWithTimeIntervalSinceNow:0.1]]; \
+    if ([timeout timeIntervalSinceNow] <= 0) { \
+      XCTFail(@"Runloop timed out before condition was met"); \
+      break; \
+    } \
+  } \
+}
+
+// Must be declared before RCTTestCustomSetBridgeModule in order to trigger the
+// race condition that we are testing for - namely that the
+// RCTDidInitializeModuleNotification for RCTTestViewManager gets sent before
+// setBridge: is called on RCTTestCustomSetBridgeModule
+@interface RCTTestViewManager : RCTViewManager
+@end
+
+@implementation RCTTestViewManager
+
+@synthesize bridge = _bridge;
+@synthesize methodQueue = _methodQueue;
+
+RCT_EXPORT_MODULE()
+
+- (void)setBridge:(RCTBridge *)bridge
+{
+  _bridge = bridge;
+  (void)[_bridge uiManager]; // Needed to trigger a race condition
+}
+
+- (NSArray<NSString *> *)customDirectEventTypes
+{
+  return @[@"foo"];
+}
+
+@end
+
+
+@interface RCTNotificationObserverModule : NSObject <RCTBridgeModule>
+
+@property (nonatomic, assign) BOOL didDetectViewManagerInit;
+
+@end
+
+@implementation RCTNotificationObserverModule
+
+@synthesize bridge = _bridge;
+
+RCT_EXPORT_MODULE()
+
+- (void)setBridge:(RCTBridge *)bridge
+{
+  _bridge = bridge;
+  [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(didInitViewManager:) name:RCTDidInitializeModuleNotification object:nil];
+}
+
+- (void)didInitViewManager:(NSNotification *)note
+{
+  id<RCTBridgeModule> module = note.userInfo[@"module"];
+  if ([module isKindOfClass:[RCTTestViewManager class]]) {
+    _didDetectViewManagerInit = YES;
+  }
+}
+
+- (void)dealloc
+{
+  [[NSNotificationCenter defaultCenter] removeObserver:self];
+}
+
+@end
+
+
+@interface RCTModuleInitNotificationRaceTests : XCTestCase <RCTBridgeDelegate>
+{
+  RCTBridge *_bridge;
+  RCTNotificationObserverModule *_notificationObserver;
+}
+@end
+
+@implementation RCTModuleInitNotificationRaceTests
+
+- (NSURL *)sourceURLForBridge:(__unused RCTBridge *)bridge
+{
+  return nil;
+}
+
+- (NSArray *)extraModulesForBridge:(__unused RCTBridge *)bridge
+{
+  return @[_notificationObserver];
+}
+
+- (void)setUp
+{
+  [super setUp];
+
+  _notificationObserver = [RCTNotificationObserverModule new];
+  _bridge = [[RCTBridge alloc] initWithDelegate:self launchOptions:nil];
+}
+
+- (void)tearDown
+{
+  [super tearDown];
+
+  _notificationObserver = nil;
+  id<RCTJavaScriptExecutor> jsExecutor = _bridge.batchedBridge.javaScriptExecutor;
+  [_bridge invalidate];
+  RUN_RUNLOOP_WHILE(jsExecutor.isValid);
+  _bridge = nil;
+}
+
+- (void)testViewManagerNotInitializedBeforeSetBridgeModule
+{
+  RUN_RUNLOOP_WHILE(!_notificationObserver.didDetectViewManagerInit);
+}
+
+@end