test_task.py 文件源码

def testFailurePropagation(self):
        # Tests if the failure of the errback of the deferred returned by the
        # callable is propagated to the lc errback.
        #
        # To make sure this test does not hang trial when LoopingCall does not
        # wait for the callable's deferred, it also checks there are no
        # calls in the clock's callLater queue.
        timings = [0.3]
        clock = task.Clock()

        def foo():
            d = defer.Deferred()
            clock.callLater(0.3, d.errback, TestException())
            return d

        lc = TestableLoopingCall(clock, foo)
        d = lc.start(1)
        self.assertFailure(d, TestException)

        clock.pump(timings)
        self.failIf(clock.calls)
        return d