Functions for running the run loop during tests with Xcode.

Async test functions

/*
 Functions for firing a runloop while performing asynchronous tests. Add them at the top of the .m file.
 
 -(void)testExample {
     __block NSInteger count = 0;
 
     dispatch_async(dispatch_get_main_queue(), ^{
         count = 1;       
     });

     WAIT_FOR(0.1);

     XCTAssert(count == 1, "Async block did not execute.");
 }
*/


#pragma mark - async functions
static void WAIT_ON_CONDITION(BOOL(^condition)(void), NSTimeInterval relativeTimeout) {
    NSTimeInterval absoluteTimeout = [NSDate timeIntervalSinceReferenceDate] + relativeTimeout;

    while (!condition()) {
        BOOL didTimeout = absoluteTimeout < [NSDate timeIntervalSinceReferenceDate];
        if (didTimeout) return;
        [[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:[NSDate dateWithTimeIntervalSinceNow:0.1]];
    }
}



static void WAIT_FOR(NSTimeInterval relativeTimeout) {
    NSTimeInterval absoluteTimeout = [NSDate timeIntervalSinceReferenceDate] + relativeTimeout;
    WAIT_ON_CONDITION(^BOOL{
        return absoluteTimeout < [NSDate timeIntervalSinceReferenceDate];
    }, relativeTimeout);
}