Fix time_bound_deferred to throw the right exception

Due to a failure to instantiate DeferredTimedOutError, time_bound_deferred
would throw a CancelledError when the deferred timed out, which was rather
confusing.

1 files changed, 33 insertions, 0 deletions

diff --git a/tests/util/test_clock.py b/tests/util/test_clock.py
new file mode 100644
index 0000000000..9672603579
--- /dev/null
+++ b/tests/util/test_clock.py
@@ -0,0 +1,33 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 Vector Creations Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from synapse import util
+from twisted.internet import defer
+from tests import unittest
+
+
+class ClockTestCase(unittest.TestCase):
+    @defer.inlineCallbacks
+    def test_time_bound_deferred(self):
+        # just a deferred which never resolves
+        slow_deferred = defer.Deferred()
+
+        clock = util.Clock()
+        time_bound = clock.time_bound_deferred(slow_deferred, 0.001)
+
+        try:
+            yield time_bound
+            self.fail("Expected timedout error, but got nothing")
+        except util.DeferredTimedOutError:
+            pass