Fake Notification Centre

README.markdown

FakeNotificationCentre

A ghetto mock for ease of unit testing methods that interact with the NotificationCentre

Based on the work by Graham Lee in Test-Driven iOS Development

FakeNotificationCentre.h

//
//  FakeNotificationCentre.h
//
//  After Graham Lee
//
//  Ghetto mock for unit testing.

#import <Foundation/Foundation.h>


@interface FakeNotificationCentre : NSObject

#pragma mark - Observers
- (void)addObserver: (id)observer selector:(SEL)aSelector name:(NSString *)aName object:(id)anObject;
- (void)removeObserver: (id)observer;
- (void)removeObserver: (id)observer name: (NSString *)aName object: (id)obj;
- (BOOL)hasObject: (id)observer forNotification: (NSString *)aName;

#pragma mark - Notifications

- (void)postNotification:(NSNotification *)notification;
- (void)postNotificationName:(NSString *)notificationName object:(id)notificationSender userInfo:(NSDictionary *)userInfo;
- (BOOL)didReceiveNotification: (NSString *)name fromObject: (id)obj;
//- (BOOL)didReceiveNotification:(NSString *)name object:(id)obj userInfo:(NSDictionary *)userInfo;

@end

FakeNotificationCentre.m

//
//  FakeNotificationCentre.m
//
//  After Graham Lee
//
//  Ghetto mock for unit testing.

#import "FakeNotificationCentre.h"
#import <SenTestingKit/SenTestCase_Macros.h>

@implementation FakeNotificationCentre {
    NSMutableDictionary *_observers;
    NSMutableArray *_notifications;
}

#pragma mark - Set up and tear down

- (id)init {
    if (!(self = [super init])) {
        return nil; // Bail!
    }

    _observers = [NSMutableDictionary new];
    _notifications = [NSMutableArray new];
    return self;
}

#pragma mark - Observers

- (void)addObserver:(id)observer selector:(SEL)aSelector name:(NSString *)aName object:(id)anObject {
    [_observers setObject:observer forKey:aName];
}

- (void)removeObserver:(id)observer {
    [[_observers copy]  enumerateKeysAndObjectsUsingBlock: ^(id key, id obj, BOOL *stop) {
        if ([obj isEqual:observer]) {
            [_observers removeObjectForKey: key];
        }
    }];
}

- (void)removeObserver:(id)observer name:(NSString *)aName object:(id)obj {
    [self removeObserver:observer];
}

- (BOOL)hasObject:(id)observer forNotification:(NSString *)aName {
    return [[_observers objectForKey:aName] isEqual:observer];
}

#pragma mark - Notifications

- (void)postNotification:(NSNotification *)notification {
    [_notifications addObject:notification];
}

- (void)postNotificationName:(NSString *)notificationName object:(id)notificationSender userInfo:(NSDictionary *)userInfo {
    NSNotification *note = [NSNotification notificationWithName:notificationName object:notificationSender userInfo:userInfo];

    [self postNotification:note];
}

- (BOOL)didReceiveNotification:(NSString *)name fromObject:(id)obj {
    for (NSNotification *note in _notifications) {
        if ([[note name] isEqualToString:name] && [[note object] isEqual:obj]) {
            return YES;
        }
    }
    return NO;
}


@end

Still more methods to implement, and figure out how to test the removal of objects from the notification centre.