bpo-44863: Allow generic typing.TypedDict (#27663)

Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
Co-authored-by: Yurii Karabas <1998uriyyo@gmail.com>
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

Lib/test/test_typing.py

@@ -4530,9 +4530,16 @@ class Point2D(TypedDict):
     x: int
     y: int
 
+class Point2DGeneric(Generic[T], TypedDict):
+    a: T
+    b: T
+
 class Bar(_typed_dict_helper.Foo, total=False):
     b: int
 
+class BarGeneric(_typed_dict_helper.FooGeneric[T], total=False):
+    b: int
+
 class LabelPoint2D(Point2D, Label): ...
 
 class Options(TypedDict, total=False):
@@ -5890,6 +5897,17 @@ class TypedDictTests(BaseTestCase):
             EmpDnew = pickle.loads(ZZ)
             self.assertEqual(EmpDnew({'name': 'jane', 'id': 37}), jane)
 
+    def test_pickle_generic(self):
+        point = Point2DGeneric(a=5.0, b=3.0)
+        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+            z = pickle.dumps(point, proto)
+            point2 = pickle.loads(z)
+            self.assertEqual(point2, point)
+            self.assertEqual(point2, {'a': 5.0, 'b': 3.0})
+            ZZ = pickle.dumps(Point2DGeneric, proto)
+            Point2DGenericNew = pickle.loads(ZZ)
+            self.assertEqual(Point2DGenericNew({'a': 5.0, 'b': 3.0}), point)
+
     def test_optional(self):
         EmpD = TypedDict('EmpD', {'name': str, 'id': int})
 
@@ -6074,6 +6092,124 @@ class TypedDictTests(BaseTestCase):
             {'a': typing.Optional[int], 'b': int}
         )
 
+    def test_get_type_hints_generic(self):
+        self.assertEqual(
+            get_type_hints(BarGeneric),
+            {'a': typing.Optional[T], 'b': int}
+        )
+
+        class FooBarGeneric(BarGeneric[int]):
+            c: str
+
+        self.assertEqual(
+            get_type_hints(FooBarGeneric),
+            {'a': typing.Optional[T], 'b': int, 'c': str}
+        )
+
+    def test_generic_inheritance(self):
+        class A(TypedDict, Generic[T]):
+            a: T
+
+        self.assertEqual(A.__bases__, (Generic, dict))
+        self.assertEqual(A.__orig_bases__, (TypedDict, Generic[T]))
+        self.assertEqual(A.__mro__, (A, Generic, dict, object))
+        self.assertEqual(A.__parameters__, (T,))
+        self.assertEqual(A[str].__parameters__, ())
+        self.assertEqual(A[str].__args__, (str,))
+
+        class A2(Generic[T], TypedDict):
+            a: T
+
+        self.assertEqual(A2.__bases__, (Generic, dict))
+        self.assertEqual(A2.__orig_bases__, (Generic[T], TypedDict))
+        self.assertEqual(A2.__mro__, (A2, Generic, dict, object))
+        self.assertEqual(A2.__parameters__, (T,))
+        self.assertEqual(A2[str].__parameters__, ())
+        self.assertEqual(A2[str].__args__, (str,))
+
+        class B(A[KT], total=False):
+            b: KT
+
+        self.assertEqual(B.__bases__, (Generic, dict))
+        self.assertEqual(B.__orig_bases__, (A[KT],))
+        self.assertEqual(B.__mro__, (B, Generic, dict, object))
+        self.assertEqual(B.__parameters__, (KT,))
+        self.assertEqual(B.__total__, False)
+        self.assertEqual(B.__optional_keys__, frozenset(['b']))
+        self.assertEqual(B.__required_keys__, frozenset(['a']))
+
+        self.assertEqual(B[str].__parameters__, ())
+        self.assertEqual(B[str].__args__, (str,))
+        self.assertEqual(B[str].__origin__, B)
+
+        class C(B[int]):
+            c: int
+
+        self.assertEqual(C.__bases__, (Generic, dict))
+        self.assertEqual(C.__orig_bases__, (B[int],))
+        self.assertEqual(C.__mro__, (C, Generic, dict, object))
+        self.assertEqual(C.__parameters__, ())
+        self.assertEqual(C.__total__, True)
+        self.assertEqual(C.__optional_keys__, frozenset(['b']))
+        self.assertEqual(C.__required_keys__, frozenset(['a', 'c']))
+        assert C.__annotations__ == {
+            'a': T,
+            'b': KT,
+            'c': int,
+        }
+        with self.assertRaises(TypeError):
+            C[str]
+
+
+        class Point3D(Point2DGeneric[T], Generic[T, KT]):
+            c: KT
+
+        self.assertEqual(Point3D.__bases__, (Generic, dict))
+        self.assertEqual(Point3D.__orig_bases__, (Point2DGeneric[T], Generic[T, KT]))
+        self.assertEqual(Point3D.__mro__, (Point3D, Generic, dict, object))
+        self.assertEqual(Point3D.__parameters__, (T, KT))
+        self.assertEqual(Point3D.__total__, True)
+        self.assertEqual(Point3D.__optional_keys__, frozenset())
+        self.assertEqual(Point3D.__required_keys__, frozenset(['a', 'b', 'c']))
+        assert Point3D.__annotations__ == {
+            'a': T,
+            'b': T,
+            'c': KT,
+        }
+        self.assertEqual(Point3D[int, str].__origin__, Point3D)
+
+        with self.assertRaises(TypeError):
+            Point3D[int]
+
+        with self.assertRaises(TypeError):
+            class Point3D(Point2DGeneric[T], Generic[KT]):
+                c: KT
+
+    def test_implicit_any_inheritance(self):
+        class A(TypedDict, Generic[T]):
+            a: T
+
+        class B(A[KT], total=False):
+            b: KT
+
+        class WithImplicitAny(B):
+            c: int
+
+        self.assertEqual(WithImplicitAny.__bases__, (Generic, dict,))
+        self.assertEqual(WithImplicitAny.__mro__, (WithImplicitAny, Generic, dict, object))
+        # Consistent with GenericTests.test_implicit_any
+        self.assertEqual(WithImplicitAny.__parameters__, ())
+        self.assertEqual(WithImplicitAny.__total__, True)
+        self.assertEqual(WithImplicitAny.__optional_keys__, frozenset(['b']))
+        self.assertEqual(WithImplicitAny.__required_keys__, frozenset(['a', 'c']))
+        assert WithImplicitAny.__annotations__ == {
+            'a': T,
+            'b': KT,
+            'c': int,
+        }
+        with self.assertRaises(TypeError):
+            WithImplicitAny[str]
+
     def test_non_generic_subscript(self):
         # For backward compatibility, subscription works
         # on arbitrary TypedDict types.