Method test_shield_effect

Lib/test/test_asyncio/test_tasks.py:2165–2187

(self)

        self.assertEqual(res, 42)

    def test_shield_effect(self):
        # Cancelling outer() does not affect inner().
        proof = 0
        waiter = self.new_future(self.loop)

        async def inner():
            nonlocal proof
            await waiter
            proof += 1

        async def outer():
            nonlocal proof
            await asyncio.shield(inner())
            proof += 100

        f = asyncio.ensure_future(outer(), loop=self.loop)
        test_utils.run_briefly(self.loop)
        f.cancel()
        with self.assertRaises(asyncio.CancelledError):
            self.loop.run_until_complete(f)
        waiter.set_result(None)
        test_utils.run_briefly(self.loop)
        self.assertEqual(proof, 1)

    def test_shield_gather(self):
        child1 = self.new_future(self.loop)