     XCTAssertEqual(val, 1)
     
     let now = NSDate()
-    XCTAssertTrue(now.timeIntervalSinceDate(then) > 0.4)
-    XCTAssertTrue(now.timeIntervalSinceDate(then) < 0.6)
+    XCTAssertTrue(now.timeIntervalSinceDate(then) > 0.4 && now.timeIntervalSinceDate(then) < 0.6)
   }
   
   func testQueueAndAwaitBlock() {

    var barrierVal: Int32 = 0

    for (var i = 0; i < 100; ++i) {
      queue.queueBlock({ OSAtomicIncrement32(&val); return })
    }
    queue.queueBarrierBlock({
      barrierVal = val
      semaphore.signal()
    })
    for (var i = 0; i < 100; ++i) {
      queue.queueBlock({ OSAtomicIncrement32(&val); return })
    }

    semaphore.wait()

    let queue = GCDQueue.concurrentQueue()
    var val: Int32 = 0
    
    queue.queueAndAwaitBlock({ _ in OSAtomicIncrement32(&val) }, iterationCount: 100)

    XCTAssertEqual(val, 100)
  }
