Fix crash due to recursive class duplication.

Possible fix for #270.
wix · Sep 19, 2017 · be92e81 · be92e81
1 parent d882d0e
commit be92e81
Showing 1 changed file with 17 additions and 10 deletions.
diff --git a/detox/ios/Detox/DetoxAppDelegateProxy.m b/detox/ios/Detox/DetoxAppDelegateProxy.m
@@ -32,27 +32,34 @@ + (void)load
 	Method m = class_getInstanceMethod([UIApplication class], @selector(setDelegate:));
 	void (*orig)(id, SEL, id<UIApplicationDelegate>) = (void*)method_getImplementation(m);
 	method_setImplementation(m, imp_implementationWithBlock(^ (id _self, id<UIApplicationDelegate> origDelegate) {
-		NSString* clsName = [NSString stringWithFormat:@"%@(%@)", NSStringFromClass([origDelegate class]), NSStringFromClass([DetoxAppDelegateProxy class])];
-		Class cls = objc_getClass(clsName.UTF8String);
-
-		if(cls == nil)
+		//Only create a dupe class if the provided instance is not already a dupe class.
+		if([origDelegate respondsToSelector:@selector(__dtx_canaryInTheCoalMine)] == NO)
 		{
-			cls = objc_duplicateClass([DetoxAppDelegateProxy class], clsName.UTF8String, 0);
+
+			NSString* clsName = [NSString stringWithFormat:@"%@(%@)", NSStringFromClass([origDelegate class]), NSStringFromClass([DetoxAppDelegateProxy class])];
+			Class cls = objc_getClass(clsName.UTF8String);
+
+			if(cls == nil)
+			{
+				cls = objc_duplicateClass([DetoxAppDelegateProxy class], clsName.UTF8String, 0);
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wdeprecated"
-			class_setSuperclass(cls, origDelegate.class);
+				class_setSuperclass(cls, origDelegate.class);
 #pragma clang diagnostic pop
+			}
+
+			object_setClass(origDelegate, cls);
+
+			[[NSNotificationCenter defaultCenter] addObserver:origDelegate selector:@selector(__dtx_applicationDidLaunchNotification:) name:UIApplicationDidFinishLaunchingNotification object:nil];
 		}
 
-		object_setClass(origDelegate, cls);
-
 		_currentAppDelegateProxy = origDelegate;
 		orig(_self, @selector(setDelegate:), origDelegate);
-
-		[[NSNotificationCenter defaultCenter] addObserver:origDelegate selector:@selector(__dtx_applicationDidLaunchNotification:) name:UIApplicationDidFinishLaunchingNotification object:nil];
 	}));
 }
 
+- (void)__dtx_canaryInTheCoalMine {}
+
 - (void)__dtx_applicationDidLaunchNotification:(NSNotification*)notification
 {
 	[self.userNotificationDispatcher dispatchOnAppDelegate:self simulateDuringLaunch:YES];