Bug report

traceback.walk_stack(None) omits the calling frame, making it equivalent to traceback.walk_stack(inspect.currentframe().f_back). Given the documentation just says "If f is None, the current stack is used.", I would have expected traceback.walk_stack(None) to be equivalent to traceback.walk_stack(inspect.currentframe()).

Example code

The following code

import traceback
import inspect

def abc():
    print(list(traceback.walk_stack(None)))
    print(list(traceback.walk_stack(inspect.currentframe())))
    print(list(traceback.walk_stack(inspect.currentframe().f_back)))

abc()

has as output

[(<frame at 0x7f66ac559a40, file '/home/vincenttc/data/temp/test/test.py', line 10, code <module>>, 10)]
[(<frame at 0x7f66ac55fa60, file '/home/vincenttc/data/temp/test/test.py', line 7, code abc>, 7), (<frame at 0x7f66ac559a40, file '/home/vincenttc/data/temp/test/test.py', line 10, code <module>>, 10)]
[(<frame at 0x7f66ac559a40, file '/home/vincenttc/data/temp/test/test.py', line 10, code <module>>, 10)]

Note that the frame for abc is missing in the first and last line.

Your environment

• CPython versions tested on: 3.8.10 (Ubuntu 20.04), 3.10.5 (Arch Linux)

• PR: GH-96092: restore frame height of traceback.walk_stack to that of pyt… #99015

• PR: gh-96092: Fix traceback.walk_stack(None) skipping too many frames #129330