test: Directly raise on timeout in UntilEvent.wait .

caucase/test.py

@@ -189,10 +189,9 @@ class UntilEvent(object):
     timeout (float)
       Maximum number of seconds to wait for.
     """
-    result = self._wait_event.wait(timeout)
-    if result:
-      self._wait_event.clear()
-    return result
+    if not self._wait_event.wait(timeout): # pragma: no cover
+      raise AssertionError('Timeout reached')
+    self._wait_event.clear()
 
   def __call__(self, deadline):
     """
@@ -1953,7 +1952,7 @@ class CaucaseTest(unittest.TestCase):
     updater_thread.daemon = True
     updater_thread.start()
     try:
-      self.assertTrue(until_updater.wait())
+      until_updater.wait()
       # CSR must have been submitted
       csr_line_list = self._runClient(
         '--user-key', user_key_path,
@@ -1969,7 +1968,7 @@ class CaucaseTest(unittest.TestCase):
       until_updater.action = ON_EVENT_EXPIRE
       updater_event.set()
       # Wait for it to call "until()" again
-      self.assertTrue(until_updater.wait())
+      until_updater.wait()
       # It must have retrieved the certificate now.
       self.assertTrue(os.path.exists(re_crt_path))
     finally:
@@ -1992,14 +1991,14 @@ class CaucaseTest(unittest.TestCase):
       443 if parsed_url.port == 80 else parsed_url.port + 1,
     )
     # Wait for server to sleep, and clear.
-    self.assertTrue(self._server_until.wait())
+    self._server_until.wait()
     # Pull certificate.
     before = ssl.get_server_certificate(address)
     # Wake server so it renews certificate.
     self._server_until.action = ON_EVENT_EXPIRE
     self._server_event.set()
     # Wait for it to be back to sleep.
-    self.assertTrue(self._server_until.wait())
+    self._server_until.wait()
     # Verify renewal happened.
     after = ssl.get_server_certificate(address)
     self.assertNotEqual(before, after)