gh-118814: Fix the TypeVar constructor when name is passed by keyword (GH-122664)

Fix _PyArg_UnpackKeywordsWithVararg for the case when argument for
positional-or-keyword parameter is passed by keyword.
There was only one such case in the stdlib -- the TypeVar constructor.

2 files changed, 70 insertions, 5 deletions

diff --git a/Lib/test/test_clinic.py b/Lib/test/test_clinic.py
index f3fd610..8d511ab 100644
--- a/Lib/test/test_clinic.py
+++ b/Lib/test/test_clinic.py
@@ -3334,11 +3334,27 @@ class ClinicFunctionalTest(unittest.TestCase):
         self.assertEqual(ac_tester.vararg(1, 2, 3, 4), (1, (2, 3, 4)))
 
     def test_vararg_with_default(self):
-        with self.assertRaises(TypeError):
-            ac_tester.vararg_with_default()
-        self.assertEqual(ac_tester.vararg_with_default(1, b=False), (1, (), False))
-        self.assertEqual(ac_tester.vararg_with_default(1, 2, 3, 4), (1, (2, 3, 4), False))
-        self.assertEqual(ac_tester.vararg_with_default(1, 2, 3, 4, b=True), (1, (2, 3, 4), True))
+        fn = ac_tester.vararg_with_default
+        self.assertRaises(TypeError, fn)
+        self.assertRaises(TypeError, fn, 1, a=2)
+        self.assertEqual(fn(1, b=2), (1, (), True))
+        self.assertEqual(fn(1, 2, 3, 4), (1, (2, 3, 4), False))
+        self.assertEqual(fn(1, 2, 3, 4, b=5), (1, (2, 3, 4), True))
+        self.assertEqual(fn(a=1), (1, (), False))
+        self.assertEqual(fn(a=1, b=2), (1, (), True))
+
+    def test_vararg_with_default2(self):
+        fn = ac_tester.vararg_with_default2
+        self.assertRaises(TypeError, fn)
+        self.assertRaises(TypeError, fn, 1, a=2)
+        self.assertEqual(fn(1, b=2), (1, (), 2, None))
+        self.assertEqual(fn(1, b=2, c=3), (1, (), 2, 3))
+        self.assertEqual(fn(1, 2, 3), (1, (2, 3), None, None))
+        self.assertEqual(fn(1, 2, 3, b=4), (1, (2, 3), 4, None))
+        self.assertEqual(fn(1, 2, 3, b=4, c=5), (1, (2, 3), 4, 5))
+        self.assertEqual(fn(a=1), (1, (), None, None))
+        self.assertEqual(fn(a=1, b=2), (1, (), 2, None))
+        self.assertEqual(fn(a=1, b=2, c=3), (1, (), 2, 3))
 
     def test_vararg_with_only_defaults(self):
         self.assertEqual(ac_tester.vararg_with_only_defaults(), ((), None))
diff --git a/Lib/test/test_typing.py b/Lib/test/test_typing.py
index 290b3c6..8baa415 100644
--- a/Lib/test/test_typing.py
+++ b/Lib/test/test_typing.py
@@ -579,6 +579,55 @@ class TypeVarTests(BaseTestCase):
         self.assertEqual(T.__name__, "T")
         self.assertEqual(T.__constraints__, ())
         self.assertIs(T.__bound__, None)
+        self.assertIs(T.__default__, typing.NoDefault)
+        self.assertIs(T.__covariant__, False)
+        self.assertIs(T.__contravariant__, False)
+        self.assertIs(T.__infer_variance__, False)
+
+        T = TypeVar(name="T", bound=type)
+        self.assertEqual(T.__name__, "T")
+        self.assertEqual(T.__constraints__, ())
+        self.assertIs(T.__bound__, type)
+        self.assertIs(T.__default__, typing.NoDefault)
+        self.assertIs(T.__covariant__, False)
+        self.assertIs(T.__contravariant__, False)
+        self.assertIs(T.__infer_variance__, False)
+
+        T = TypeVar(name="T", default=())
+        self.assertEqual(T.__name__, "T")
+        self.assertEqual(T.__constraints__, ())
+        self.assertIs(T.__bound__, None)
+        self.assertIs(T.__default__, ())
+        self.assertIs(T.__covariant__, False)
+        self.assertIs(T.__contravariant__, False)
+        self.assertIs(T.__infer_variance__, False)
+
+        T = TypeVar(name="T", covariant=True)
+        self.assertEqual(T.__name__, "T")
+        self.assertEqual(T.__constraints__, ())
+        self.assertIs(T.__bound__, None)
+        self.assertIs(T.__default__, typing.NoDefault)
+        self.assertIs(T.__covariant__, True)
+        self.assertIs(T.__contravariant__, False)
+        self.assertIs(T.__infer_variance__, False)
+
+        T = TypeVar(name="T", contravariant=True)
+        self.assertEqual(T.__name__, "T")
+        self.assertEqual(T.__constraints__, ())
+        self.assertIs(T.__bound__, None)
+        self.assertIs(T.__default__, typing.NoDefault)
+        self.assertIs(T.__covariant__, False)
+        self.assertIs(T.__contravariant__, True)
+        self.assertIs(T.__infer_variance__, False)
+
+        T = TypeVar(name="T", infer_variance=True)
+        self.assertEqual(T.__name__, "T")
+        self.assertEqual(T.__constraints__, ())
+        self.assertIs(T.__bound__, None)
+        self.assertIs(T.__default__, typing.NoDefault)
+        self.assertIs(T.__covariant__, False)
+        self.assertIs(T.__contravariant__, False)
+        self.assertIs(T.__infer_variance__, True)
 
 
 class TypeParameterDefaultsTests(BaseTestCase):