bpo-39245: Switch to public API for Vectorcall (GH-18460)

The bulk of this patch was generated automatically with:

    for name in \
        PyObject_Vectorcall \
        Py_TPFLAGS_HAVE_VECTORCALL \
        PyObject_VectorcallMethod \
        PyVectorcall_Function \
        PyObject_CallOneArg \
        PyObject_CallMethodNoArgs \
        PyObject_CallMethodOneArg \
    ;
    do
        echo $name
        git grep -lwz _$name | xargs -0 sed -i "s/\b_$name\b/$name/g"
    done

    old=_PyObject_FastCallDict
    new=PyObject_VectorcallDict
    git grep -lwz $old | xargs -0 sed -i "s/\b$old\b/$new/g"

and then cleaned up:

- Revert changes to in docs & news
- Revert changes to backcompat defines in headers
- Nudge misaligned comments

1 files changed, 3 insertions, 3 deletions

diff --git a/Lib/test/test_call.py b/Lib/test/test_call.py
index d178aa4ec2..b3077ad1d1 100644
--- a/Lib/test/test_call.py
+++ b/Lib/test/test_call.py
@@ -468,7 +468,7 @@ class FastCallTests(unittest.TestCase):
                     self.check_result(result, expected)
 
     def test_vectorcall_dict(self):
-        # Test _PyObject_FastCallDict()
+        # Test PyObject_VectorcallDict()
 
         for func, args, expected in self.CALLS_POSARGS:
             with self.subTest(func=func, args=args):
@@ -487,7 +487,7 @@ class FastCallTests(unittest.TestCase):
                 self.check_result(result, expected)
 
     def test_vectorcall(self):
-        # Test _PyObject_Vectorcall()
+        # Test PyObject_Vectorcall()
 
         for func, args, expected in self.CALLS_POSARGS:
             with self.subTest(func=func, args=args):
@@ -594,7 +594,7 @@ class TestPEP590(unittest.TestCase):
         # 1. vectorcall using PyVectorcall_Call()
         #   (only for objects that support vectorcall directly)
         # 2. normal call
-        # 3. vectorcall using _PyObject_Vectorcall()
+        # 3. vectorcall using PyObject_Vectorcall()
         # 4. call as bound method
         # 5. call using functools.partial