def test__fire_propagates_error_from_hook(self):
error = factory.make_exception()
dhooks = DeferredHooks()
d = Deferred()
d.addCallback(lambda _: Failure(error))
dhooks.add(d)
self.assertRaises(type(error), dhooks.fire)
def test__fire_calls_hooks(self):
dhooks = DeferredHooks()
ds = Deferred(), Deferred()
for d in ds:
dhooks.add(d)
dhooks.fire()
for d in ds:
self.assertIsNone(extract_result(d))
def test__savepoint_saves_and_restores_hooks(self):
d = Deferred()
dhooks = DeferredHooks()
dhooks.add(d)
with dhooks.savepoint():
self.expectThat(list(dhooks.hooks), Equals([]))
self.expectThat(list(dhooks.hooks), Equals([d]))
def test__reset_cancels_all_hooks(self):
canceller = Mock()
dhooks = DeferredHooks()
d1, d2 = Deferred(canceller), Deferred(canceller)
dhooks.add(d1)
dhooks.add(d2)
dhooks.reset()
self.assertThat(dhooks.hooks, HasLength(0))
self.assertThat(canceller, MockCallsMatch(call(d1), call(d2)))
def test__reset_suppresses_CancelledError(self):
logger = self.useFixture(TwistedLoggerFixture())
dhooks = DeferredHooks()
d = Deferred()
dhooks.add(d)
dhooks.reset()
self.assertThat(dhooks.hooks, HasLength(0))
self.assertThat(extract_result(d), Is(None))
self.assertEqual("", logger.output)
def test__fire_always_consumes_all_hooks(self):
dhooks = DeferredHooks()
d1, d2 = Deferred(), Deferred()
d1.addCallback(lambda _: 0 / 0) # d1 will fail.
dhooks.add(d1)
dhooks.add(d2)
self.assertRaises(ZeroDivisionError, dhooks.fire)
self.assertThat(dhooks.hooks, HasLength(0))
self.assertThat(d1, IsFiredDeferred())
self.assertThat(d2, IsFiredDeferred())
def test__fire_calls_hooks_in_reactor(self):
def validate_in_reactor(_):
self.assertTrue(isInIOThread())
dhooks = DeferredHooks()
d = Deferred()
d.addCallback(validate_in_reactor)
dhooks.add(d)
dhooks.fire()
self.assertThat(d, IsFiredDeferred())
def test__savepoint_restores_hooks_with_new_hooks_on_clean_exit(self):
d1 = Deferred()
d2 = Deferred()
dhooks = DeferredHooks()
dhooks.add(d1)
with dhooks.savepoint():
dhooks.add(d2)
self.expectThat(list(dhooks.hooks), Equals([d2]))
self.expectThat(list(dhooks.hooks), Equals([d1, d2]))
def test__reset_cancels_in_reactor(self):
def validate_in_reactor(_):
self.assertTrue(isInIOThread())
dhooks = DeferredHooks()
d = Deferred()
d.addBoth(validate_in_reactor)
dhooks.add(d)
dhooks.reset()
self.assertThat(dhooks.hooks, HasLength(0))
self.assertThat(d, IsFiredDeferred())
def test__savepoint_restores_hooks_only_on_dirty_exit(self):
d1 = Deferred()
d2 = Deferred()
dhooks = DeferredHooks()
dhooks.add(d1)
exception_type = factory.make_exception_type()
with ExpectedException(exception_type):
with dhooks.savepoint():
dhooks.add(d2)
raise exception_type()
self.expectThat(list(dhooks.hooks), Equals([d1]))
def test__logs_failures_from_cancelled_hooks(self):
logger = self.useFixture(TwistedLoggerFixture())
error = factory.make_exception()
dhooks = DeferredHooks()
d = Deferred()
d.addBoth(lambda _: Failure(error))
dhooks.add(d)
dhooks.reset()
self.assertThat(dhooks.hooks, HasLength(0))
self.assertThat(d, IsFiredDeferred())
self.assertDocTestMatches(
dedent("""\
Failure when cancelling hook.
Traceback (most recent call last):
...
maastesting.factory.TestException#...
"""), logger.output)
def test__logs_failures_from_cancellers_when_hook_already_fired(self):
logger = self.useFixture(TwistedLoggerFixture())
def canceller(d):
d.callback(None)
raise factory.make_exception()
dhooks = DeferredHooks()
d = Deferred(canceller)
dhooks.add(d)
dhooks.reset()
self.assertThat(dhooks.hooks, HasLength(0))
self.assertThat(d, IsFiredDeferred())
self.assertDocTestMatches(
dedent("""\
Failure when cancelling hook.
Traceback (most recent call last):
...
maastesting.factory.TestException#...
"""), logger.output)
def test__logs_failures_from_cancellers(self):
logger = self.useFixture(TwistedLoggerFixture())
canceller = Mock()
canceller.side_effect = factory.make_exception()
dhooks = DeferredHooks()
d = Deferred(canceller)
dhooks.add(d)
dhooks.reset()
self.assertThat(dhooks.hooks, HasLength(0))
# The hook has not been fired, but because the user-supplied canceller
# has failed we're not in a position to know what to do. This reflects
# a programming error and not a run-time error that we ought to be
# prepared for, so it is left as-is.
self.assertThat(d, IsUnfiredDeferred())
self.assertDocTestMatches(
dedent("""\
Failure when cancelling hook.
Traceback (most recent call last):
...
maastesting.factory.TestException#...
"""), logger.output)
def test__add_appends_Deferred_to_queue(self):
dhooks = DeferredHooks()
self.assertThat(dhooks.hooks, HasLength(0))
dhooks.add(Deferred())
self.assertThat(dhooks.hooks, HasLength(1))