stack_context_test.py 文件源码

def test_yield_in_with(self):
        @gen.engine
        def f():
            self.callback = yield gen.Callback('a')
            with StackContext(functools.partial(self.context, 'c1')):
                # This yield is a problem: the generator will be suspended
                # and the StackContext's __exit__ is not called yet, so
                # the context will be left on _state.contexts for anything
                # that runs before the yield resolves.
                yield gen.Wait('a')

        with self.assertRaises(StackContextInconsistentError):
            f()
            self.wait()
        # Cleanup: to avoid GC warnings (which for some reason only seem
        # to show up on py33-asyncio), invoke the callback (which will do
        # nothing since the gen.Runner is already finished) and delete it.
        self.callback()
        del self.callback