Mocking expectations in Kiwi (iOS) for a delegate

问题:

Short version of the question:

What is wrong with the following Kiwi/iOS mock expectation?

[[mockDelegate should] receive:@selector(connectionDidSucceedWithText:andStatus:) withArguments:[testString1 stringByAppendingString:testString2],theValue(value),nil];

Long version of question:

I am trying to write a test in Kiwi, iOS for a simple class that handles a NSConnection. To test that the class handles the callback from the NSConnection I send it the delegate methods NSConnection normally does. I have a delegate in the class that sends data back to whoever uses my class. To test my class I have to inject a mocked delegate and then check that my desired methods are called. Simple as that :)

My code for the Kiwi test is:

//Some ivars declared elsewhere:
testString1 = @"asd323/4 d14";
testString2 = @"as98 /2y9h3fdd14";
testData1 = [testString1 dataUsingEncoding:NSUTF8StringEncoding];
testData2 = [testString2 dataUsingEncoding:NSUTF8StringEncoding];
mockURLRespons = [NSHTTPURLResponse mock];
int value = 11111;
id mockDelegate = [KWMock mockForProtocol:@protocol(SharepointConnectionDelegate)];
communicator = [[SharepointCommunicator alloc] init];

it (@"should send recieve data back to delegate2", ^{
   [communicator setDelegate:mockDelegate];
   [mockURLRespons stub:@selector(statusCode) andReturn:theValue(value)];
   [(id)communicator connection:niceMockConnector didReceiveResponse:mockURLRespons];
   [(id)communicator connection:niceMockConnector didReceiveData:testData1];
   [(id)communicator connection:niceMockConnector didReceiveData:testData2];
   [(id)communicator connectionDidFinishLoading:niceMockConnector]; 

   [[mockDelegate should] receive:@selector(connectionDidSucceedWithText:andStatus:) withArguments:[testString1 stringByAppendingString:testString2],theValue(value),nil];

});

And in my SharepointCommunicator.m:

-(void)connection:(NSURLConnection *)aConnection didReceiveResponse:(NSURLResponse *)response {
  if (connection != aConnection) {
      [connection cancel];
      connection = aConnection;
  }
  responseData = [[NSMutableData alloc] init];
  statusCode = [(NSHTTPURLResponse*)response statusCode];
}

-(void)connection:(NSURLConnection *)aConnection didReceiveData:(NSData *)data {
  if (aConnection != self.connection)
    return;
  [responseData appendData:data];
}

-(void)connectionDidFinishLoading:(NSURLConnection *)connection {
  NSString *txt = [[NSString alloc] initWithData:responseData encoding: NSASCIIStringEncoding];
  NSLog(@"Statuscode: %i", statusCode);
  NSLog(@"Data is: %@",txt);
  [delegate connectionDidSucceedWithText:txt andStatus:statusCode];
  [self.connection cancel];
  self.connection = nil;
}

This code works and is correct. Debugging it with checkpoint shows it does as expected. The values of statusCode is 11111. and txt is testString1+textString2. Still it fails on the last row on in the test with the following error:

error: -[kiwiSharepointCommunicatorTest Sharepointcommunicator_AStateTheComponentIsIn_ShouldSendRecieveDataBackToDelegate2] : 'Sharepointcommunicator, a state the component is in, should send recieve data back to delegate2' [FAILED], mock received unexpected message -connectionDidSucceedWithText："asd323/4 d14as98 /2y9h3fdd14" andStatus：11111 
Test Case '-[kiwiSharepointCommunicatorTest Sharepointcommunicator_AStateTheComponentIsIn_ShouldSendRecieveDataBackToDelegate2]' failed (3.684 seconds).

Removing the last row in the test still generate the same error. I guess my understanding of receive:withArguments: is wrong..

回答1:

You have to call [[mockDelegate should] receive... before the call to connectionDidFinishLoading to prepare the mockDelegate for the message it's about to receive.