gh-139817: Attribute __qualname__ is added to TypeAliasType (#139919)

Author: efimov-mikhail

Doc/library/typing.rst

@@ -2243,7 +2243,7 @@ without the dedicated syntax, as documented below.
    .. versionadded:: 3.10
 
 
-.. class:: TypeAliasType(name, value, *, type_params=())
+.. class:: TypeAliasType(name, value, *, type_params=(), qualname=None)
 
    The type of type aliases created through the :keyword:`type` statement.
 
@@ -2267,6 +2267,20 @@ without the dedicated syntax, as documented below.
          >>> Alias.__name__
          'Alias'
 
+   .. attribute:: __qualname__
+
+      The :term:`qualified name` of the type alias:
+
+      .. doctest::
+
+        >>> class Class:
+        ...     type Alias = int
+        ...
+        >>> Class.Alias.__qualname__
+        'Class.Alias'
+
+   .. versionadded:: 3.15
+
    .. attribute:: __module__
 
       The name of the module in which the type alias was defined::

Include/internal/pycore_global_objects_fini_generated.h

@@ -697,6 +697,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(ps1)
         STRUCT_FOR_ID(ps2)
         STRUCT_FOR_ID(qid)
+        STRUCT_FOR_ID(qualname)
         STRUCT_FOR_ID(query)
         STRUCT_FOR_ID(queuetype)
         STRUCT_FOR_ID(quotetabs)

Include/internal/pycore_global_strings.h

@@ -8,6 +8,11 @@
     Callable, TypeAliasType, TypeVar, TypeVarTuple, ParamSpec, Unpack, get_args,
 )
 
+type GlobalTypeAlias = int
+
+def get_type_alias():
+    type TypeAliasInFunc = str
+    return TypeAliasInFunc
 
 class TypeParamsInvalidTest(unittest.TestCase):
     def test_name_collisions(self):
@@ -70,6 +75,8 @@ def inner[B](self):
 
 
 class TypeParamsAliasValueTest(unittest.TestCase):
+    type TypeAliasInClass = dict
+
     def test_alias_value_01(self):
         type TA1 = int
 
@@ -142,33 +149,67 @@ def test_subscripting(self):
         self.assertIs(specialized2.__origin__, VeryGeneric)
         self.assertEqual(specialized2.__args__, (int, str, float, [bool, range]))
 
+    def test___name__(self):
+        type TypeAliasLocal = GlobalTypeAlias
+
+        self.assertEqual(GlobalTypeAlias.__name__, 'GlobalTypeAlias')
+        self.assertEqual(get_type_alias().__name__, 'TypeAliasInFunc')
+        self.assertEqual(self.TypeAliasInClass.__name__, 'TypeAliasInClass')
+        self.assertEqual(TypeAliasLocal.__name__, 'TypeAliasLocal')
+
+        with self.assertRaisesRegex(
+            AttributeError,
+            "readonly attribute",
+        ):
+            setattr(TypeAliasLocal, '__name__', 'TA')
+
+    def test___qualname__(self):
+        type TypeAliasLocal = GlobalTypeAlias
+
+        self.assertEqual(GlobalTypeAlias.__qualname__,
+                         'GlobalTypeAlias')
+        self.assertEqual(get_type_alias().__qualname__,
+                         'get_type_alias.<locals>.TypeAliasInFunc')
+        self.assertEqual(self.TypeAliasInClass.__qualname__,
+                         'TypeParamsAliasValueTest.TypeAliasInClass')
+        self.assertEqual(TypeAliasLocal.__qualname__,
+                         'TypeParamsAliasValueTest.test___qualname__.<locals>.TypeAliasLocal')
+
+        with self.assertRaisesRegex(
+            AttributeError,
+            "readonly attribute",
+        ):
+            setattr(TypeAliasLocal, '__qualname__', 'TA')
+
     def test_repr(self):
         type Simple = int
-        type VeryGeneric[T, *Ts, **P] = Callable[P, tuple[T, *Ts]]
+        self.assertEqual(repr(Simple), Simple.__qualname__)
 
-        self.assertEqual(repr(Simple), "Simple")
-        self.assertEqual(repr(VeryGeneric), "VeryGeneric")
+        type VeryGeneric[T, *Ts, **P] = Callable[P, tuple[T, *Ts]]
+        self.assertEqual(repr(VeryGeneric), VeryGeneric.__qualname__)
+        fullname = f"{VeryGeneric.__module__}.{VeryGeneric.__qualname__}"
         self.assertEqual(repr(VeryGeneric[int, bytes, str, [float, object]]),
-                         "VeryGeneric[int, bytes, str, [float, object]]")
+                         f"{fullname}[int, bytes, str, [float, object]]")
         self.assertEqual(repr(VeryGeneric[int, []]),
-                         "VeryGeneric[int, []]")
+                         f"{fullname}[int, []]")
         self.assertEqual(repr(VeryGeneric[int, [VeryGeneric[int], list[str]]]),
-                         "VeryGeneric[int, [VeryGeneric[int], list[str]]]")
+                         f"{fullname}[int, [{fullname}[int], list[str]]]")
 
     def test_recursive_repr(self):
         type Recursive = Recursive
-        self.assertEqual(repr(Recursive), "Recursive")
+        self.assertEqual(repr(Recursive), Recursive.__qualname__)
 
         type X = list[Y]
         type Y = list[X]
-        self.assertEqual(repr(X), "X")
-        self.assertEqual(repr(Y), "Y")
+        self.assertEqual(repr(X), X.__qualname__)
+        self.assertEqual(repr(Y), Y.__qualname__)
 
         type GenericRecursive[X] = list[X | GenericRecursive[X]]
-        self.assertEqual(repr(GenericRecursive), "GenericRecursive")
-        self.assertEqual(repr(GenericRecursive[int]), "GenericRecursive[int]")
+        self.assertEqual(repr(GenericRecursive), GenericRecursive.__qualname__)
+        fullname = f"{GenericRecursive.__module__}.{GenericRecursive.__qualname__}"
+        self.assertEqual(repr(GenericRecursive[int]), f"{fullname}[int]")
         self.assertEqual(repr(GenericRecursive[GenericRecursive[int]]),
-                         "GenericRecursive[GenericRecursive[int]]")
+                         f"{fullname}[{fullname}[int]]")
 
     def test_raising(self):
         type MissingName = list[_My_X]
@@ -193,15 +234,25 @@ class TypeAliasConstructorTest(unittest.TestCase):
     def test_basic(self):
         TA = TypeAliasType("TA", int)
         self.assertEqual(TA.__name__, "TA")
+        self.assertEqual(TA.__qualname__, "TA")
         self.assertIs(TA.__value__, int)
         self.assertEqual(TA.__type_params__, ())
         self.assertEqual(TA.__module__, __name__)
 
+    def test_with_qualname(self):
+        TA = TypeAliasType("TA", str, qualname="Class.TA")
+        self.assertEqual(TA.__name__, "TA")
+        self.assertEqual(TA.__qualname__, "Class.TA")
+        self.assertIs(TA.__value__, str)
+        self.assertEqual(TA.__type_params__, ())
+        self.assertEqual(TA.__module__, __name__)
+
     def test_attributes_with_exec(self):
         ns = {}
         exec("type TA = int", ns, ns)
         TA = ns["TA"]
         self.assertEqual(TA.__name__, "TA")
+        self.assertEqual(TA.__qualname__, "TA")
         self.assertIs(TA.__value__, int)
         self.assertEqual(TA.__type_params__, ())
         self.assertIs(TA.__module__, None)
@@ -210,6 +261,7 @@ def test_generic(self):
         T = TypeVar("T")
         TA = TypeAliasType("TA", list[T], type_params=(T,))
         self.assertEqual(TA.__name__, "TA")
+        self.assertEqual(TA.__qualname__, "TA")
         self.assertEqual(TA.__value__, list[T])
         self.assertEqual(TA.__type_params__, (T,))
         self.assertEqual(TA.__module__, __name__)
@@ -218,6 +270,7 @@ def test_generic(self):
     def test_not_generic(self):
         TA = TypeAliasType("TA", list[int], type_params=())
         self.assertEqual(TA.__name__, "TA")
+        self.assertEqual(TA.__qualname__, "TA")
         self.assertEqual(TA.__value__, list[int])
         self.assertEqual(TA.__type_params__, ())
         self.assertEqual(TA.__module__, __name__)
@@ -268,8 +321,9 @@ def test_expects_type_like(self):
             TypeAliasType("A", int, type_params=(T, 2))
 
     def test_keywords(self):
-        TA = TypeAliasType(name="TA", value=int)
+        TA = TypeAliasType(name="TA", value=int, type_params=(), qualname=None)
         self.assertEqual(TA.__name__, "TA")
+        self.assertEqual(TA.__qualname__, "TA")
         self.assertIs(TA.__value__, int)
         self.assertEqual(TA.__type_params__, ())
         self.assertEqual(TA.__module__, __name__)
@@ -283,6 +337,8 @@ def test_errors(self):
             TypeAliasType("TA", list, ())
         with self.assertRaises(TypeError):
             TypeAliasType("TA", list, type_params=42)
+        with self.assertRaises(TypeError):
+            TypeAliasType("TA", list, qualname=range(5))
 
 
 class TypeAliasTypeTest(unittest.TestCase):

Include/internal/pycore_runtime_init_generated.h

@@ -0,0 +1,2 @@
+Attribute ``__qualname__`` is added to :class:`typing.TypeAliasType`.
+Patch by Mikhail Efimov.