+ raise StopIteration
+
+ if user_seek_beginning is not None:
+ MySourceIter._user_seek_beginning = user_seek_beginning
+
+ if user_can_seek_beginning is not None:
+ MySourceIter._user_can_seek_beginning = property(user_can_seek_beginning)
+
+ class MySource(bt2._UserSourceComponent, message_iterator_class=MySourceIter):
+ def __init__(self, params, obj):
+ tc = self._create_trace_class()
+ sc = tc.create_stream_class(supports_packets=True)
+ ec = sc.create_event_class()
+
+ self._add_output_port('out', (tc, sc, ec))
+
+ class MyFilterIter(bt2._UserMessageIterator):
+ def __init__(self, port):
+ self._upstream_iter = self._create_input_port_message_iterator(
+ self._component._input_ports['in']
+ )
+
+ def __next__(self):
+ return next(self._upstream_iter)
+
+ @property
+ def _user_can_seek_beginning(self):
+ return self._upstream_iter.can_seek_beginning
+
+ def _user_seek_beginning(self):
+ self._upstream_iter.seek_beginning()
+
+ class MyFilter(bt2._UserFilterComponent, message_iterator_class=MyFilterIter):
+ def __init__(self, params, obj):
+ self._add_input_port('in')
+ self._add_output_port('out')
+
+ return _create_graph(MySource, sink_cls, flt_comp_cls=MyFilter)
+
+
+class UserMessageIteratorSeekBeginningTestCase(unittest.TestCase):
+ def test_can_seek_beginning(self):
+ class MySink(bt2._UserSinkComponent):
+ def __init__(self, params, obj):
+ self._add_input_port('in')
+
+ def _user_graph_is_configured(self):
+ self._msg_iter = self._create_input_port_message_iterator(
+ self._input_ports['in']
+ )
+
+ def _user_consume(self):
+ nonlocal can_seek_beginning
+ can_seek_beginning = self._msg_iter.can_seek_beginning
+
+ def _user_can_seek_beginning(self):
+ nonlocal input_port_iter_can_seek_beginning
+ return input_port_iter_can_seek_beginning
+
+ graph = _setup_seek_test(
+ MySink, user_can_seek_beginning=_user_can_seek_beginning
+ )
+
+ input_port_iter_can_seek_beginning = True
+ can_seek_beginning = None
+ graph.run_once()
+ self.assertTrue(can_seek_beginning)
+
+ input_port_iter_can_seek_beginning = False
+ can_seek_beginning = None
+ graph.run_once()
+ self.assertFalse(can_seek_beginning)
+
+ def test_no_can_seek_beginning_with_seek_beginning(self):
+ # Test an iterator without a _user_can_seek_beginning method, but with
+ # a _user_seek_beginning method.
+ class MySink(bt2._UserSinkComponent):
+ def __init__(self, params, obj):
+ self._add_input_port('in')
+
+ def _user_graph_is_configured(self):
+ self._msg_iter = self._create_input_port_message_iterator(
+ self._input_ports['in']
+ )
+
+ def _user_consume(self):
+ nonlocal can_seek_beginning
+ can_seek_beginning = self._msg_iter.can_seek_beginning
+
+ def _user_seek_beginning(self):
+ pass
+
+ graph = _setup_seek_test(MySink, user_seek_beginning=_user_seek_beginning)
+ can_seek_beginning = None
+ graph.run_once()
+ self.assertTrue(can_seek_beginning)
+
+ def test_no_can_seek_beginning(self):
+ # Test an iterator without a _user_can_seek_beginning method, without
+ # a _user_seek_beginning method.
+ class MySink(bt2._UserSinkComponent):
+ def __init__(self, params, obj):
+ self._add_input_port('in')
+
+ def _user_graph_is_configured(self):
+ self._msg_iter = self._create_input_port_message_iterator(
+ self._input_ports['in']
+ )
+
+ def _user_consume(self):
+ nonlocal can_seek_beginning
+ can_seek_beginning = self._msg_iter.can_seek_beginning
+
+ graph = _setup_seek_test(MySink)
+ can_seek_beginning = None
+ graph.run_once()
+ self.assertFalse(can_seek_beginning)
+
+ def test_can_seek_beginning_user_error(self):
+ class MySink(bt2._UserSinkComponent):
+ def __init__(self, params, obj):
+ self._add_input_port('in')
+
+ def _user_graph_is_configured(self):
+ self._msg_iter = self._create_input_port_message_iterator(
+ self._input_ports['in']
+ )
+
+ def _user_consume(self):
+ # This is expected to raise.
+ self._msg_iter.can_seek_beginning
+
+ def _user_can_seek_beginning(self):
+ raise ValueError('moustiquaire')
+
+ graph = _setup_seek_test(
+ MySink, user_can_seek_beginning=_user_can_seek_beginning
+ )
+
+ with self.assertRaises(bt2._Error) as ctx:
+ graph.run_once()
+
+ cause = ctx.exception[0]
+ self.assertIn('ValueError: moustiquaire', cause.message)
+
+ def test_can_seek_beginning_wrong_return_value(self):
+ class MySink(bt2._UserSinkComponent):
+ def __init__(self, params, obj):
+ self._add_input_port('in')
+
+ def _user_graph_is_configured(self):
+ self._msg_iter = self._create_input_port_message_iterator(
+ self._input_ports['in']
+ )
+
+ def _user_consume(self):
+ # This is expected to raise.
+ self._msg_iter.can_seek_beginning
+
+ def _user_can_seek_beginning(self):
+ return 'Amqui'
+
+ graph = _setup_seek_test(
+ MySink, user_can_seek_beginning=_user_can_seek_beginning
+ )
+
+ with self.assertRaises(bt2._Error) as ctx:
+ graph.run_once()
+
+ cause = ctx.exception[0]
+ self.assertIn("TypeError: 'str' is not a 'bool' object", cause.message)
+
+ def test_seek_beginning(self):
+ class MySink(bt2._UserSinkComponent):
+ def __init__(self, params, obj):
+ self._add_input_port('in')
+
+ def _user_graph_is_configured(self):
+ self._msg_iter = self._create_input_port_message_iterator(
+ self._input_ports['in']
+ )
+
+ def _user_consume(self):
+ nonlocal do_seek_beginning
+ nonlocal msg
+
+ if do_seek_beginning:
+ self._msg_iter.seek_beginning()
+ return
+
+ msg = next(self._msg_iter)
+
+ def _user_seek_beginning(self):
+ self._at = 0
+
+ msg = None
+ graph = _setup_seek_test(MySink, user_seek_beginning=_user_seek_beginning)
+
+ # Consume message.
+ do_seek_beginning = False
+ graph.run_once()
+ self.assertIs(type(msg), bt2._StreamBeginningMessageConst)
+
+ # Consume message.
+ graph.run_once()
+ self.assertIs(type(msg), bt2._PacketBeginningMessageConst)
+
+ # Seek beginning.
+ do_seek_beginning = True
+ graph.run_once()
+
+ # Consume message.
+ do_seek_beginning = False
+ graph.run_once()
+ self.assertIs(type(msg), bt2._StreamBeginningMessageConst)
+
+ def test_seek_beginning_user_error(self):
+ class MySink(bt2._UserSinkComponent):
+ def __init__(self, params, obj):
+ self._add_input_port('in')
+
+ def _user_graph_is_configured(self):
+ self._msg_iter = self._create_input_port_message_iterator(
+ self._input_ports['in']
+ )
+
+ def _user_consume(self):
+ self._msg_iter.seek_beginning()
+
+ def _user_seek_beginning(self):
+ raise ValueError('ouch')
+
+ graph = _setup_seek_test(MySink, user_seek_beginning=_user_seek_beginning)
+
+ with self.assertRaises(bt2._Error):
+ graph.run_once()
+
+
+if __name__ == '__main__':
+ unittest.main()