2 files changed, 62 insertions, 4 deletions
diff --git a/tests/util/test_linearizer.py b/tests/util/test_linearizer.py
index afcba482f9..793a88e462 100644
--- a/tests/util/test_linearizer.py
+++ b/tests/util/test_linearizer.py
@@ -12,8 +12,7 @@
 # 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.util import async, logcontext
 from tests import unittest
 
 from twisted.internet import defer
@@ -38,7 +37,28 @@ class LinearizerTestCase(unittest.TestCase):
         with cm1:
             self.assertFalse(d2.called)
 
-        self.assertTrue(d2.called)
-
         with (yield d2):
             pass
+
+    def test_lots_of_queued_things(self):
+        # we have one slow thing, and lots of fast things queued up behind it.
+        # it should *not* explode the stack.
+        linearizer = Linearizer()
+
+        @defer.inlineCallbacks
+        def func(i, sleep=False):
+            with logcontext.LoggingContext("func(%s)" % i) as lc:
+                with (yield linearizer.queue("")):
+                    self.assertEqual(
+                        logcontext.LoggingContext.current_context(), lc)
+                    if sleep:
+                        yield async.sleep(0)
+
+                self.assertEqual(
+                    logcontext.LoggingContext.current_context(), lc)
+
+        func(0, sleep=True)
+        for i in xrange(1, 100):
+            func(i)
+
+        return func(1000)
diff --git a/tests/util/test_log_context.py b/tests/util/test_logcontext.py
index 9ffe209c4d..e2f7765f49 100644
--- a/tests/util/test_log_context.py
+++ b/tests/util/test_logcontext.py
@@ -94,3 +94,41 @@ class LoggingContextTestCase(unittest.TestCase):
                 yield defer.succeed(None)
 
         return self._test_preserve_fn(nonblocking_function)
+
+    @defer.inlineCallbacks
+    def test_make_deferred_yieldable(self):
+        # a function which retuns an incomplete deferred, but doesn't follow
+        # the synapse rules.
+        def blocking_function():
+            d = defer.Deferred()
+            reactor.callLater(0, d.callback, None)
+            return d
+
+        sentinel_context = LoggingContext.current_context()
+
+        with LoggingContext() as context_one:
+            context_one.test_key = "one"
+
+            d1 = logcontext.make_deferred_yieldable(blocking_function())
+            # make sure that the context was reset by make_deferred_yieldable
+            self.assertIs(LoggingContext.current_context(), sentinel_context)
+
+            yield d1
+
+            # now it should be restored
+            self._check_test_key("one")
+
+    @defer.inlineCallbacks
+    def test_make_deferred_yieldable_on_non_deferred(self):
+        """Check that make_deferred_yieldable does the right thing when its
+        argument isn't actually a deferred"""
+
+        with LoggingContext() as context_one:
+            context_one.test_key = "one"
+
+            d1 = logcontext.make_deferred_yieldable("bum")
+            self._check_test_key("one")
+
+            r = yield d1
+            self.assertEqual(r, "bum")
+            self._check_test_key("one")