Unit tests may be skipped

[dodikk]

Some tests contain static guards against second launch.
In this case they will pass but won't check anything.

- (void)testAddClassMethodIfNeedWithSelector
{
    static BOOL firstTestRun = YES;

    if (firstTestRun) {
    }

}

---

Please use comments or XCTFail() for such cases.

- (void)testAddClassMethodIfNeedWithSelector
{
    static BOOL firstTestRun = YES;

    if (firstTestRun) {
    }
    else
    {
        XCTFail( @"Test cannot be run twice" );
        return;
    }
}