How to use the uavcan.dsdl.parser.PrimitiveType function in uavcan

def test_unsigned_saturated_33bit(self):
        dtype = parser.PrimitiveType(
            parser.PrimitiveType.KIND_UNSIGNED_INT,
            33,
            parser.PrimitiveType.CAST_MODE_SATURATED)
        value = transport.cast(0, dtype)
        self.assertEqual(value, 0)
        value = transport.cast(8589934591, dtype)
        self.assertEqual(value, 8589934591)
        value = transport.cast(8589934592, dtype)
        self.assertEqual(value, 8589934591)
        value = transport.cast(-1, dtype)
        self.assertEqual(value, 0)

def test_unsigned_saturated_64bit(self):
        dtype = parser.PrimitiveType(
            parser.PrimitiveType.KIND_UNSIGNED_INT,
            64,
            parser.PrimitiveType.CAST_MODE_SATURATED)
        value = transport.cast(0, dtype)
        self.assertEqual(value, 0)
        value = transport.cast(18446744073709551615, dtype)
        self.assertEqual(value, 18446744073709551615)
        value = transport.cast(-1, dtype)
        self.assertEqual(value, 0)
        value = transport.cast(18446744073709551617, dtype)
        self.assertEqual(value, 18446744073709551615)
        value = transport.cast(-18446744073709551615, dtype)
        self.assertEqual(value, 0)

def test_truncated_33bit(self):
        dtype = parser.PrimitiveType(
            parser.PrimitiveType.KIND_UNSIGNED_INT,
            33,
            parser.PrimitiveType.CAST_MODE_TRUNCATED)
        value = transport.cast(0, dtype)
        self.assertEqual(value, 0)
        value = transport.cast(8589934591, dtype)
        self.assertEqual(value, 8589934591)
        value = transport.cast(8589934592, dtype)
        self.assertEqual(value, 0)
        value = transport.cast(-1, dtype)
        self.assertEqual(value, 8589934591)

def test_truncated_1bit(self):
        dtype = parser.PrimitiveType(
            parser.PrimitiveType.KIND_UNSIGNED_INT,
            1,
            parser.PrimitiveType.CAST_MODE_TRUNCATED)
        value = transport.cast(0, dtype)
        self.assertEqual(value, 0)
        value = transport.cast(1, dtype)
        self.assertEqual(value, 1)
        value = transport.cast(2, dtype)
        self.assertEqual(value, 0)
        value = transport.cast(-1, dtype)
        self.assertEqual(value, 1)
        value = transport.cast(5, dtype)
        self.assertEqual(value, 1)
        value = transport.cast(-10, dtype)
        self.assertEqual(value, 0)

def make_float(bitlen):
            return parser.PrimitiveType(parser.PrimitiveType.KIND_FLOAT, bitlen,
                                        parser.PrimitiveType.CAST_MODE_TRUNCATED)

parser.ArrayType.MODE_DYNAMIC,
                    5
                ),
                "c"
            )
        ]

        def custom_type_factory(*args, **kwargs):
            return transport.CompoundValue(custom_type, *args, **kwargs)
        custom_type._instantiate = custom_type_factory

        self.a1_type = parser.ArrayType(
            parser.PrimitiveType(
                parser.PrimitiveType.KIND_SIGNED_INT,
                8,
                parser.PrimitiveType.CAST_MODE_TRUNCATED
            ),
            parser.ArrayType.MODE_STATIC,
            4
        )
        self.a2_type = parser.ArrayType(
            parser.PrimitiveType(
                parser.PrimitiveType.KIND_FLOAT,
                16,
                parser.PrimitiveType.CAST_MODE_SATURATED
            ),
            parser.ArrayType.MODE_STATIC,
            2
        )
        self.a3_type = parser.ArrayType(
            custom_type,
            parser.ArrayType.MODE_STATIC,

(0,0),
            ""
        )
        self.custom_type.union = True
        self.custom_type.fields = [
            parser.Field(
                parser.PrimitiveType(
                    parser.PrimitiveType.KIND_FLOAT,
                    16,
                    parser.PrimitiveType.CAST_MODE_SATURATED
                ),
                "a"
            ),
            parser.Field(
                parser.ArrayType(
                    parser.PrimitiveType(
                        parser.PrimitiveType.KIND_UNSIGNED_INT,
                        8,
                        parser.PrimitiveType.CAST_MODE_SATURATED
                    ),
                    parser.ArrayType.MODE_STATIC,
                    2
                ),
                "b"
            )
        ]

        def custom_type_factory(*args, **kwargs):
            return transport.CompoundValue(self.custom_type, *args,
                                           **kwargs)
        self.custom_type._instantiate = custom_type_factory

8,
                    parser.PrimitiveType.CAST_MODE_TRUNCATED
                ),
                "a"
            ),
            parser.Field(
                parser.PrimitiveType(
                    parser.PrimitiveType.KIND_FLOAT,
                    16,
                    parser.PrimitiveType.CAST_MODE_SATURATED
                ),
                "b"
            ),
            parser.Field(
                parser.ArrayType(
                    parser.PrimitiveType(
                        parser.PrimitiveType.KIND_UNSIGNED_INT,
                        1,
                        parser.PrimitiveType.CAST_MODE_SATURATED
                    ),
                    parser.ArrayType.MODE_DYNAMIC,
                    5
                ),
                "c"
            )
        ]

        def custom_type_factory(*args, **kwargs):
            return transport.CompoundValue(custom_type, *args, **kwargs)
        custom_type._instantiate = custom_type_factory

        self.a1_type = parser.ArrayType(

def _extract_fields(self, x):
        if isinstance(x, (int, float, bool, str, bytes)):
            return x
        if isinstance(x, uavcan.transport.Void) or isinstance(x.type, uavcan.dsdl.parser.VoidType): # HACK
            return None
        if isinstance(x.type, uavcan.dsdl.parser.PrimitiveType):
            return x.value
        if isinstance(x.type, uavcan.dsdl.parser.CompoundType):
            return {name: self._extract_fields(value) for name, value in x.fields.items()}
        if isinstance(x.type, uavcan.dsdl.parser.ArrayType):
            val = [self._extract_fields(y) for y in x]
            try:
                val = bytes(val)        # String handling heuristic
            except Exception:
                pass
            return val
        raise Exception('Invalid field type: %s' % x.type)