failing a XCTestCase with assert without the test continuing to run but without stopping other tests

Pascal's answer gave me the idea to achieve this properly. XCTool now behaves like OCUnit when an assertion fails: the execution of the test case is aborted immediately, tearDown invoked and the next test case is run.

Simply override the method invokeTest in your base class (the one that inherits from the XCTestCase class):

- (void)invokeTest
{
    self.continueAfterFailure = NO;

    @try
    {
        [super invokeTest];
    }
    @finally
    {
        self.continueAfterFailure = YES;
    }
}

That's it!

The easiest way is to add:

continueAfterFailure = false

into setUp() method. So it will look like this:

Swift

override func setUp() {
    super.setUp()

    continueAfterFailure = false
}

Objective-C

 - (void)setUp {
    [super setUp];

    [self setContinueAfterFailure:NO];
}

One option would be to check the condition normally, then fail and return from the test if it is false.

Something like this:

if (!condition) {
  XCFail(@"o noes");
  return;
}

You could wrap this up in a helper macro to preserve readability.

BDD test libraries like Kiwi are more elegant for this sort of thing, as they make it easier to share setup between many tests which leads to fewer assertions per test.