iOS Kiwi + Nocilla - Failing to stub request

Question

I'm just starting out with stubbing requests to test async calls to an external API with iOS. I'm currently stuck with the following code and I can't figure out what's not working.

The very simple thing I'm trying to achieve is that if I get a 200 response from a website, I change the background color of my view to green, else I tint it red.

In the - (void)viewDidLoad method of my view controller I'm calling the following method:

- (void)checkConnectivity {
    NSURL *url = [NSURL URLWithString:@"http://www.example.com/"];
    NSURLRequest *request = [NSURLRequest requestWithURL:url];
    NSURLSessionDataTask *task = [[NSURLSession sharedSession] dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
        NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)response;
        if (httpResponse.statusCode == 200) {
            dispatch_async(dispatch_get_main_queue(), ^{
                self.currentBackgroundColor = [UIColor greenColor];
                [self changeToBackgroundColor:self.currentBackgroundColor];
            });
        } else {
            dispatch_async(dispatch_get_main_queue(), ^{
                self.currentBackgroundColor = [UIColor redColor];
                [self changeToBackgroundColor:self.currentBackgroundColor];
            });
        }
    }];
    [task resume];
}

- (void)changeToBackgroundColor:(UIColor *)color {
    self.view.backgroundColor = color;
}

My Kiwi spec looks like this:

#import "Kiwi.h"
#import "Nocilla.h"
#import "TWRViewController.h"

@interface TWRViewController ()
@property (strong, nonatomic) UIColor *currentBackgroundColor;
- (void)checkConnectivity;
- (void)changeToBackgroundColor:(UIColor *)color;
@end

SPEC_BEGIN(KiwiSpec)

describe(@"When the app launches", ^{
    context(@"check if internet is available", ^{
        beforeAll(^{
            [[LSNocilla sharedInstance] start];
        });

        afterAll(^{
            [[LSNocilla sharedInstance] stop];
        });

        afterEach(^{
            [[LSNocilla sharedInstance] clearStubs];
        });

        it(@"should display a green background if there is connectivity", ^{
            stubRequest(@"GET", @"http://www.example.com/").andReturn(200);
            TWRViewController *vc = [[TWRViewController alloc] initWithNibName:@"TWRViewController" bundle:nil];
            [vc checkConnectivity];
            [[vc.currentBackgroundColor shouldEventually] equal:[UIColor greenColor]];
        });
    });
});

SPEC_END

I don't know what I'm doing wrong, but it keeps failing. Any idea?

Answer 1

Seems like your asynchronous matcher is incomplete.

You need to wrap the subject of an async matcher with expectFutureValue like this:

[[expectFutureValue(vc.currentBackgroundColor) shouldEventually] equal:[UIColor greenColor]];

For future reference, when you adding an async matcher to a primitive like a BOOL you need to add theValue on top of that, like this:

[[expectFutureValue(theValue(myBool) shouldEventually] beYes];

Hope it helps