Resolve ipc race condition

Example/SBTUITestTunnel_Tests/Info.plist

@@ -21,6 +21,6 @@
 	<key>CFBundleVersion</key>
 	<string>1</string>
 	<key>SBTUITestTunnelDisableIPC</key>
-	<true/>
+	<false/>
 </dict>
 </plist>

Sources/SBTUITestTunnelClient/SBTUITestTunnelClient.m

@@ -249,6 +249,15 @@ - (void)waitForConnection
 
 - (void)serverDidConnect:(id)sender
 {
+    while (!self.ipcConnection.isValid) {
+        if (CFAbsoluteTimeGetCurrent() - self.launchStart > SBTUITunneledApplicationDefaultTimeout) {
+            [self shutDownWithErrorMessage:@"[SBTUITestTunnel] IPC tunnel did fail to connect" code:SBTUITestTunnelErrorConnectionToApplicationFailed];
+            return;
+        }
+
+        [NSRunLoop.mainRunLoop runUntilDate:[NSDate dateWithTimeIntervalSinceNow:0.5]];
+    }
+
     __weak typeof(self)weakSelf = self;
     dispatch_async(dispatch_get_main_queue(), ^{
         weakSelf.connected = YES;

Sources/SBTUITestTunnelCommon/DetoxIPC/DTXIPCConnection.h

@@ -76,6 +76,8 @@ NS_ASSUME_NONNULL_BEGIN
 /// Invalidate the connection. All outstanding error handling blocks will be called on the message handling queue. The connection must be invalidated before it is deallocated. After a connection is invalidated, no more messages may be sent or received.
 - (void)invalidate;
 
+- (BOOL)isValid;
+
 @end
 
 NS_ASSUME_NONNULL_END

Sources/SBTUITestTunnelCommon/DetoxIPC/DTXIPCConnection.m

@@ -184,6 +184,8 @@ - (NSMethodSignature *)protocolMethodSignatureForSelector:(SEL)aSelector
 @implementation DTXIPCConnection
 {
 	dispatch_queue_t _dispatchQueue;
+    dispatch_queue_t _otherConnectionQueue;
+
 	NSRunLoop* _runLoop;
 	NSString* _actualServiceName;
 
@@ -224,7 +226,8 @@ - (instancetype)initWithServiceName:(NSString *)serviceName
 		_slave = NO;
 
 		_dispatchQueue = dispatch_queue_create([NSString stringWithFormat:@"com.wix.DTXIPCConnection:%@", _serviceName].UTF8String, dispatch_queue_attr_make_with_autorelease_frequency(NULL, DISPATCH_AUTORELEASE_FREQUENCY_WORK_ITEM));
-
+        _otherConnectionQueue = dispatch_queue_create([NSString stringWithFormat:@"com.wix.DTXIPCOtherConnection:%@", _serviceName].UTF8String, NULL);
+
 		//Attempt becoming a master
 		if([self _commonInit] == NO)
 		{
@@ -294,7 +297,12 @@ - (void)invalidate
 
 - (BOOL)isValid
 {
-	return _connection.isValid && _otherConnection.isValid;
+    __block BOOL ret = NO;
+    dispatch_sync(_otherConnectionQueue, ^{
+        ret = _connection.isValid && _otherConnection.isValid;
+    });
+
+    return ret;
 }
 
 - (id)remoteObjectProxy
@@ -323,8 +331,10 @@ - (void)setExportedObject:(id)exportedObject
 
 - (oneway void)_slaveDidConnectWithName:(NSString*)slaveServiceName
 {
-	_otherConnection = [NSConnection connectionWithRegisteredName:slaveServiceName host:nil];
-	[NSNotificationCenter.defaultCenter addObserver:self selector:@selector(_otherConnectionDidDie:) name:NSConnectionDidDieNotification object:_otherConnection];
+    dispatch_sync(_otherConnectionQueue, ^{
+        _otherConnection = [NSConnection connectionWithRegisteredName:slaveServiceName host:nil];
+        [NSNotificationCenter.defaultCenter addObserver:self selector:@selector(_otherConnectionDidDie:) name:NSConnectionDidDieNotification object:_otherConnection];
+    });
 }
 
 - (oneway void)_invokeFromRemote:(NSDictionary*)serializedInvocation

Sources/SBTUITestTunnelServer/SBTUITestTunnelServer.m

@@ -157,6 +157,7 @@ - (BOOL)takeOffOnce
 - (BOOL)takeOffOnceIPCWithServiceIdentifier:(NSString *)serviceIdentifier
 {
     self.ipcConnection = [[DTXIPCConnection alloc] initWithServiceName:[NSString stringWithFormat:@"com.subito.sbtuitesttunnel.ipc.%@", serviceIdentifier]];
+
     self.ipcConnection.remoteObjectInterface = [DTXIPCInterface interfaceWithProtocol:@protocol(SBTIPCTunnel)];
     self.ipcConnection.exportedInterface = [DTXIPCInterface interfaceWithProtocol:@protocol(SBTIPCTunnel)];
     self.ipcConnection.exportedObject = self;