cpython: 59829d7b7838 (original) (raw)

Mercurial > cpython

changeset 106221:59829d7b7838 3.5

Issue #28556: allow default values in class form of NamedTuple -- Jelle Zijlstra [#28556]

line wrap: on

line diff

--- a/Lib/test/test_typing.py +++ b/Lib/test/test_typing.py @@ -1400,6 +1400,10 @@ class G(Generic[T]): class CoolEmployee(NamedTuple): name: str cool: int + +class CoolEmployeeWithDefault(NamedTuple):

• name: str
• cool: int = 0

""" if PY36: @@ -1960,6 +1964,28 @@ class NamedTupleTests(BaseTestCase): self.assertIs(CoolEmployee._field_types, CoolEmployee.annotations) @skipUnless(PY36, 'Python 3.6 required')

• def test_annotation_usage_with_default(self):

•    jelle = CoolEmployeeWithDefault('Jelle')[](#l1.19)

•    self.assertIsInstance(jelle, CoolEmployeeWithDefault)[](#l1.20)

•    self.assertIsInstance(jelle, tuple)[](#l1.21)

•    self.assertEqual(jelle.name, 'Jelle')[](#l1.22)

•    self.assertEqual(jelle.cool, 0)[](#l1.23)

•    cooler_employee = CoolEmployeeWithDefault('Sjoerd', 1)[](#l1.24)

•    self.assertEqual(cooler_employee.cool, 1)[](#l1.25)

+

•    self.assertEqual(CoolEmployeeWithDefault.__name__, 'CoolEmployeeWithDefault')[](#l1.27)

•    self.assertEqual(CoolEmployeeWithDefault._fields, ('name', 'cool'))[](#l1.28)

•    self.assertEqual(CoolEmployeeWithDefault._field_types, dict(name=str, cool=int))[](#l1.29)

•    self.assertEqual(CoolEmployeeWithDefault._field_defaults, dict(cool=0))[](#l1.30)

+

•    with self.assertRaises(TypeError):[](#l1.32)

•        exec("""[](#l1.33)

+class NonDefaultAfterDefault(NamedTuple):

• x: int = 3
• y: int

+""") +

• @skipUnless(PY36, 'Python 3.6 required') def test_namedtuple_keyword_usage(self): LocalEmployee = NamedTuple("LocalEmployee", name=str, age=int) nick = LocalEmployee('Nick', 25)

--- a/Lib/typing.py +++ b/Lib/typing.py @@ -1959,7 +1959,22 @@ class NamedTupleMeta(type): raise TypeError("Class syntax for NamedTuple is only supported" " in Python 3.6+") types = ns.get('annotations', {})

•    return _make_nmtuple(typename, types.items())[](#l2.7)

•    nm_tpl = _make_nmtuple(typename, types.items())[](#l2.8)

•    defaults = [][](#l2.9)

•    defaults_dict = {}[](#l2.10)

•    for field_name in types:[](#l2.11)

•        if field_name in ns:[](#l2.12)

•            default_value = ns[field_name][](#l2.13)

•            defaults.append(default_value)[](#l2.14)

•            defaults_dict[field_name] = default_value[](#l2.15)

•        elif defaults:[](#l2.16)

•            raise TypeError("Non-default namedtuple field {field_name} cannot follow default"[](#l2.17)

•                            " field(s) {default_names}"[](#l2.18)

•                            .format(field_name=field_name,[](#l2.19)

•                                    default_names=', '.join(defaults_dict.keys())))[](#l2.20)

•    nm_tpl.__new__.__defaults__ = tuple(defaults)[](#l2.21)

•    nm_tpl._field_defaults = defaults_dict[](#l2.22)

•    return nm_tpl[](#l2.23)

class NamedTuple(metaclass=NamedTupleMeta): """Typed version of namedtuple.