private void assertIsNotCompleted(KafkaFutureImpl<String> future) {
        assertFalse(future.isDone());
        assertFalse(future.isCompletedExceptionally());
        assertFalse(future.isCancelled());
    }
Asserts that the given future is done, didn't fail and was cancelled.
clients/src/test/java/org/apache/kafka/common/KafkaFutureTest.java