Client:call generates TimeoutError exception when it is timed out.

Signed-off-by: Tomoya Fujita <[email protected]>

rclpy/rclpy/client.py

@@ -81,10 +81,11 @@ def call(
 
  :param request: The service request.
  :param timeout_sec: Seconds to wait. If ``None``, then wait forever.
- :return: The service response, or None if timed out.
+ :return: The service response.
  :raises: TypeError if the type of the passed request isn't an instance
  of the Request type of the provided service when the client was
  constructed.
+ :raises: TimeoutError if the response is not available within the timeout.
  """
  if not isinstance(request, self.srv_type.Request):
  raise TypeError()
@@ -105,6 +106,7 @@ def unblock(future):
  if not event.wait(timeout_sec):
  # Timed out. remove_pending_request() to free resources
  self.remove_pending_request(future)
+ raise TimeoutError()
  if future.exception() is not None:
  raise future.exception()
  return future.result()

rclpy/test/test_client.py

@@ -234,11 +234,11 @@ def _service(request, response):
  executor_thread = threading.Thread(
  target=TestClient._spin_rclpy_node, args=(self.node, executor))
  executor_thread.start()
- result = cli.call(GetParameters.Request(), 0.5)
- self.assertTrue(result is None)
+ with self.assertRaises(TimeoutError):
+ cli.call(GetParameters.Request(), 0.5)
+ finally:
  executor.shutdown()
  executor_thread.join()
- finally:
  self.node.destroy_client(cli)
  self.node.destroy_service(srv)