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How to use __init_subclass__ method in molecule

Best Python code snippet using molecule_python

test_subclassinit.py

Source:test_subclassinit.py

...4class Test(unittest.TestCase):5    def test_init_subclass(self):6        class A:7            initialized = False8            def __init_subclass__(cls):9                super().__init_subclass__()10                cls.initialized = True11        class B(A):12            pass13        self.assertFalse(A.initialized)14        self.assertTrue(B.initialized)15    def test_init_subclass_dict(self):16        class A(dict):17            initialized = False18            def __init_subclass__(cls):19                super().__init_subclass__()20                cls.initialized = True21        class B(A):22            pass23        self.assertFalse(A.initialized)24        self.assertTrue(B.initialized)25    def test_init_subclass_kwargs(self):26        class A:27            def __init_subclass__(cls, **kwargs):28                cls.kwargs = kwargs29        class B(A, x=3):30            pass31        self.assertEqual(B.kwargs, dict(x=3))32    def test_init_subclass_error(self):33        class A:34            def __init_subclass__(cls):35                raise RuntimeError36        with self.assertRaises(RuntimeError):37            class B(A):38                pass39    def test_init_subclass_wrong(self):40        class A:41            def __init_subclass__(cls, whatever):42                pass43        with self.assertRaises(TypeError):44            class B(A):45                pass46    def test_init_subclass_skipped(self):47        class BaseWithInit:48            def __init_subclass__(cls, **kwargs):49                super().__init_subclass__(**kwargs)50                cls.initialized = cls51        class BaseWithoutInit(BaseWithInit):52            pass53        class A(BaseWithoutInit):54            pass55        self.assertIs(A.initialized, A)56        self.assertIs(BaseWithoutInit.initialized, BaseWithoutInit)57    def test_init_subclass_diamond(self):58        class Base:59            def __init_subclass__(cls, **kwargs):60                super().__init_subclass__(**kwargs)61                cls.calls = []62        class Left(Base):63            pass64        class Middle:65            def __init_subclass__(cls, middle, **kwargs):66                super().__init_subclass__(**kwargs)67                cls.calls += [middle]68        class Right(Base):69            def __init_subclass__(cls, right="right", **kwargs):70                super().__init_subclass__(**kwargs)71                cls.calls += [right]72        class A(Left, Middle, Right, middle="middle"):73            pass74        self.assertEqual(A.calls, ["right", "middle"])75        self.assertEqual(Left.calls, [])76        self.assertEqual(Right.calls, [])77    def test_set_name(self):78        class Descriptor:79            def __set_name__(self, owner, name):80                self.owner = owner81                self.name = name82        class A:83            d = Descriptor()84        self.assertEqual(A.d.name, "d")85        self.assertIs(A.d.owner, A)86    def test_set_name_metaclass(self):87        class Meta(type):88            def __new__(cls, name, bases, ns):89                ret = super().__new__(cls, name, bases, ns)90                self.assertEqual(ret.d.name, "d")91                self.assertIs(ret.d.owner, ret)92                return 093        class Descriptor:94            def __set_name__(self, owner, name):95                self.owner = owner96                self.name = name97        class A(metaclass=Meta):98            d = Descriptor()99        self.assertEqual(A, 0)100    def test_set_name_error(self):101        class Descriptor:102            def __set_name__(self, owner, name):103                1/0104        with self.assertRaises(RuntimeError) as cm:105            class NotGoingToWork:106                attr = Descriptor()107        exc = cm.exception108        self.assertRegex(str(exc), r'\bNotGoingToWork\b')109        self.assertRegex(str(exc), r'\battr\b')110        self.assertRegex(str(exc), r'\bDescriptor\b')111        self.assertIsInstance(exc.__cause__, ZeroDivisionError)112    def test_set_name_wrong(self):113        class Descriptor:114            def __set_name__(self):115                pass116        with self.assertRaises(RuntimeError) as cm:117            class NotGoingToWork:118                attr = Descriptor()119        exc = cm.exception120        self.assertRegex(str(exc), r'\bNotGoingToWork\b')121        self.assertRegex(str(exc), r'\battr\b')122        self.assertRegex(str(exc), r'\bDescriptor\b')123        self.assertIsInstance(exc.__cause__, TypeError)124    def test_set_name_lookup(self):125        resolved = []126        class NonDescriptor:127            def __getattr__(self, name):128                resolved.append(name)129        class A:130            d = NonDescriptor()131        self.assertNotIn('__set_name__', resolved,132                         '__set_name__ is looked up in instance dict')133    def test_set_name_init_subclass(self):134        class Descriptor:135            def __set_name__(self, owner, name):136                self.owner = owner137                self.name = name138        class Meta(type):139            def __new__(cls, name, bases, ns):140                self = super().__new__(cls, name, bases, ns)141                self.meta_owner = self.owner142                self.meta_name = self.name143                return self144        class A:145            def __init_subclass__(cls):146                cls.owner = cls.d.owner147                cls.name = cls.d.name148        class B(A, metaclass=Meta):149            d = Descriptor()150        self.assertIs(B.owner, B)151        self.assertEqual(B.name, 'd')152        self.assertIs(B.meta_owner, B)153        self.assertEqual(B.name, 'd')154    def test_set_name_modifying_dict(self):155        notified = []156        class Descriptor:157            def __set_name__(self, owner, name):158                setattr(owner, name + 'x', None)159                notified.append(name)...

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