Method test_field_metadata_default

Lib/test/test_dataclasses/__init__.py:2050–2061

(self)

        self.assertEqual(C.from_file('filename').x, 20)

    def test_field_metadata_default(self):
        # Make sure the default metadata is read-only and of
        #  zero length.
        @dataclass
        class C:
            i: int

        self.assertFalse(fields(C)[0].metadata)
        self.assertEqual(len(fields(C)[0].metadata), 0)
        with self.assertRaisesRegex(TypeError,
                                    'does not support item assignment'):
            fields(C)[0].metadata['test'] = 3

    def test_field_metadata_mapping(self):
        # Make sure only a mapping can be passed as metadata