Question

How can I verify that passing block is execute correctly ?

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
    [self updatePostalCode:newLocation withHandler:^(NSArray *placemarks, NSError *error) {
    // code that want to test
        CLPlacemark *placemark = [placemarks objectAtIndex:0];
        self.postalCode = [placemark postalCode];
        _geocodePending = NO;
    }];

    ....
}

I want to know that postalCode, _geocodePending is set correctly, but I can’t figure out how to do this with OCMock.

Added code

id mockSelf = [OCMockObject partialMockForObject:_location];

    id mockPlacemart = (id)[OCMockObject mockForClass:[CLPlacemark class]];

    [[[mockPlacemart stub] andReturn:@"10170"] postalCode];

    [mockSelf setGeocodePending:YES];
    [mockSelf setPostalCode:@"00000"];

    [self.location handleLocationUpdate]([NSArray arrayWithObject:mockPlacemart], nil);

    STAssertFalse([mockSelf geocodePending], @"geocodePending should be FALSE");
    STAssertTrue([[mockSelf postalCode] isEqualToString:@"10170"], @"10170", @"postal is expected to be 10170 but was %@" , [mockSelf postalCode]);

Answer 1

Return your handler block from a method on your class. There are a few good reasons to do this, including testability.

- (void (^)(NSArray *, NSError *))handleLocationUpdate {
    __weak Foo *weakself = self;
    return ^(NSArray *placemarks, NSError *error) {
        CLPlacemark *placemark = [placemarks objectAtIndex:0];
        weakself.postalCode = [placemark postalCode];
        weakself.geocodePending = NO;
    }
}

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
    [self updatePostalCode:newLocation withHandler:[self handleLocationUpdate]];

    ....
}

Then, in your test:

-(void)testLocationUpdates {
    id mockPlacemark = [OCMockObject mockForClass:[CLPlacemark class]];
    [[[mockPlacemark stub] andReturn:@"99999"] postalCode];

    myClass.geocodePending = YES;
    myClass.postalCode = @"00000";

    [myClass handleLocationUpdate]([NSArray arrayWithObject:mockPlacemark], nil);

    expect(myClass.geocodePending).toBeFalsy;
    expect(myClass.postalCode).toEqual(@"99999");
}