How to use the aioquic.buffer.encode_uint_var function in aioquic

def test_handle_control_stream_duplicate(self):
        """
        We must only receive a single control stream.
        """
        quic_server = FakeQuicConnection(
            configuration=QuicConfiguration(is_client=False)
        )
        h3_server = H3Connection(quic_server)

        # receive a first control stream
        h3_server.handle_event(
            StreamDataReceived(
                stream_id=2, data=encode_uint_var(StreamType.CONTROL), end_stream=False
            )
        )

        # receive a second control stream
        h3_server.handle_event(
            StreamDataReceived(
                stream_id=6, data=encode_uint_var(StreamType.CONTROL), end_stream=False
            )
        )
        self.assertEqual(
            quic_server.closed,
            (
                ErrorCode.HTTP_STREAM_CREATION_ERROR,
                "Only one control stream is allowed",
            ),

def test_handle_max_stream_data_frame(self):
        with client_and_server() as (client, server):
            # client creates bidirectional stream 0
            stream = client._create_stream(stream_id=0)
            self.assertEqual(stream.max_stream_data_remote, 1048576)

            # client receives MAX_STREAM_DATA raising limit
            client._handle_max_stream_data_frame(
                client_receive_context(client),
                QuicFrameType.MAX_STREAM_DATA,
                Buffer(data=b"\x00" + encode_uint_var(1048577)),
            )
            self.assertEqual(stream.max_stream_data_remote, 1048577)

            # client receives MAX_STREAM_DATA lowering limit
            client._handle_max_stream_data_frame(
                client_receive_context(client),
                QuicFrameType.MAX_STREAM_DATA,
                Buffer(data=b"\x00" + encode_uint_var(1048575)),
            )
            self.assertEqual(stream.max_stream_data_remote, 1048577)

def test_handle_stream_frame_over_largest_offset(self):
        with client_and_server() as (client, server):
            # client receives offset + length > 2^62 - 1
            frame_type = QuicFrameType.STREAM_BASE | 6
            stream_id = 1
            with self.assertRaises(QuicConnectionError) as cm:
                client._handle_stream_frame(
                    client_receive_context(client),
                    frame_type,
                    Buffer(
                        data=encode_uint_var(stream_id)
                        + encode_uint_var(UINT_VAR_MAX)
                        + encode_uint_var(1)
                    ),
                )
            self.assertEqual(
                cm.exception.error_code, QuicErrorCode.FRAME_ENCODING_ERROR
            )
            self.assertEqual(cm.exception.frame_type, frame_type)
            self.assertEqual(
                cm.exception.reason_phrase, "offset + length cannot exceed 2^62 - 1"
            )

self.assertEqual(len(client._streams_blocked_uni), 0)
            self.assertEqual(roundtrip(client, server), (0, 0))

            # create one too many -> STREAMS_BLOCKED
            stream_id = 128 * 4 + 2
            client.send_stream_data(stream_id, b"")
            self.assertTrue(client._streams[stream_id].is_blocked)
            self.assertEqual(len(client._streams_blocked_bidi), 0)
            self.assertEqual(len(client._streams_blocked_uni), 1)
            self.assertEqual(roundtrip(client, server), (1, 1))

            # peer raises max streams
            client._handle_max_streams_uni_frame(
                client_receive_context(client),
                QuicFrameType.MAX_STREAMS_UNI,
                Buffer(data=encode_uint_var(129)),
            )
            self.assertFalse(client._streams[stream_id].is_blocked)

def test_handle_qpack_encoder_stream_error(self):
        """
        Receiving garbage on the QPACK encoder stream triggers an exception.
        """
        quic_client = FakeQuicConnection(
            configuration=QuicConfiguration(is_client=True)
        )
        h3_client = H3Connection(quic_client)

        h3_client.handle_event(
            StreamDataReceived(
                stream_id=7,
                data=encode_uint_var(StreamType.QPACK_ENCODER) + b"\x00",
                end_stream=False,
            )
        )
        self.assertEqual(
            quic_client.closed, (ErrorCode.HTTP_QPACK_ENCODER_STREAM_ERROR, "")
        )

def test_handle_stream_frame_over_largest_offset(self):
        with client_and_server() as (client, server):
            # client receives offset + length > 2^62 - 1
            frame_type = QuicFrameType.STREAM_BASE | 6
            stream_id = 1
            with self.assertRaises(QuicConnectionError) as cm:
                client._handle_stream_frame(
                    client_receive_context(client),
                    frame_type,
                    Buffer(
                        data=encode_uint_var(stream_id)
                        + encode_uint_var(UINT_VAR_MAX)
                        + encode_uint_var(1)
                    ),
                )
            self.assertEqual(
                cm.exception.error_code, QuicErrorCode.FRAME_ENCODING_ERROR
            )
            self.assertEqual(cm.exception.frame_type, frame_type)
            self.assertEqual(
                cm.exception.reason_phrase, "offset + length cannot exceed 2^62 - 1"
            )

with client_and_server() as (client, server):
            self.assertEqual(client._remote_max_streams_uni, 128)

            # client receives MAX_STREAMS_UNI raising limit
            client._handle_max_streams_uni_frame(
                client_receive_context(client),
                QuicFrameType.MAX_STREAMS_UNI,
                Buffer(data=encode_uint_var(129)),
            )
            self.assertEqual(client._remote_max_streams_uni, 129)

            # client receives MAX_STREAMS_UNI raising limit
            client._handle_max_streams_uni_frame(
                client_receive_context(client),
                QuicFrameType.MAX_STREAMS_UNI,
                Buffer(data=encode_uint_var(127)),
            )
            self.assertEqual(client._remote_max_streams_uni, 129)

def _create_uni_stream(self, stream_type: int) -> int:
        """
        Create an unidirectional stream of the given type.
        """
        stream_id = self._quic.get_next_available_stream_id(is_unidirectional=True)
        self._quic.send_stream_data(stream_id, encode_uint_var(stream_type))
        return stream_id