From 158e0937eb56f14dd851549939037de499526fd2 Mon Sep 17 00:00:00 2001 From: Sean Quah <8349537+squahtx@users.noreply.github.com> Date: Fri, 4 Mar 2022 13:10:05 +0000 Subject: [PATCH] Add test for `ObservableDeferred`'s cancellation behaviour (#12149) Signed-off-by: Sean Quah --- changelog.d/12149.misc | 1 + tests/util/test_async_helpers.py | 28 ++++++++++++++++++++++++++++ 2 files changed, 29 insertions(+) create mode 100644 changelog.d/12149.misc diff --git a/changelog.d/12149.misc b/changelog.d/12149.misc new file mode 100644 index 0000000000..d39af96723 --- /dev/null +++ b/changelog.d/12149.misc @@ -0,0 +1 @@ +Add test for `ObservableDeferred`'s cancellation behaviour. diff --git a/tests/util/test_async_helpers.py b/tests/util/test_async_helpers.py index 362014f4cb..ff53ce114b 100644 --- a/tests/util/test_async_helpers.py +++ b/tests/util/test_async_helpers.py @@ -100,6 +100,34 @@ class ObservableDeferredTest(TestCase): self.assertEqual(str(results[0].value), "gah!", "observer 1 errback result") self.assertEqual(str(results[1].value), "gah!", "observer 2 errback result") + def test_cancellation(self): + """Test that cancelling an observer does not affect other observers.""" + origin_d: "Deferred[int]" = Deferred() + observable = ObservableDeferred(origin_d, consumeErrors=True) + + observer1 = observable.observe() + observer2 = observable.observe() + observer3 = observable.observe() + + self.assertFalse(observer1.called) + self.assertFalse(observer2.called) + self.assertFalse(observer3.called) + + # cancel the second observer + observer2.cancel() + self.assertFalse(observer1.called) + self.failureResultOf(observer2, CancelledError) + self.assertFalse(observer3.called) + + # other observers resolve as normal + origin_d.callback(123) + self.assertEqual(observer1.result, 123, "observer 1 callback result") + self.assertEqual(observer3.result, 123, "observer 3 callback result") + + # additional observers resolve as normal + observer4 = observable.observe() + self.assertEqual(observer4.result, 123, "observer 4 callback result") + class TimeoutDeferredTest(TestCase): def setUp(self):