pylint Crash with AstroidError "StatementMissing: Statement not found on"

[John-Robbins]

There were several other bug reports (#8210, #8079) but the first was on Windows, the second on Debian, but I'm on macOS Also, I was just starting a prototype of command line argument processing so the code for the crash is very simple.

(Thanks to all the contributors for pylint!)

Bug description

When parsing the following a.py:

"""A prototype."""

import argparse


class TestClass:
    """Something."""

    def do_the_args(self: "TestClass") -> None:
        """Something."""
        parser = argparse.ArgumentParser(description="XXXXXXXX")

        parser.add_argument("-c",
                            "--command",
                            action="store",
                            help="xxxxxx")
        parser.add_argument("-n",
                            "--nologo",
                            action="store_true",
                            help="xxxxx")
        parser.add_argument("program",
                            action="store",
                            help="xxxxx")
        args = parser.parse_args()

        print(f"command = {args.command}")
        print(f"nologo  = {args.nologo}")
        print(f"file    = {args.file}")


def main() -> None:
    """Something."""
    x: TestClass = TestClass()
    x.do_the_args()


if __name__ == "__main__":
    main()

Command used

pylint a.py

Pylint output

pylint crashed with a ``AstroidError`` and with the following stacktrace:

Traceback (most recent call last):
  File "/Users/johnrobbins/.vscode/extensions/ms-python.pylint-2023.10.1/bundled/libs/pylint/lint/pylinter.py", line 788, in _lint_file
    check_astroid_module(module)
  File "/Users/johnrobbins/.vscode/extensions/ms-python.pylint-2023.10.1/bundled/libs/pylint/lint/pylinter.py", line 1017, in check_astroid_module
    retval = self._check_astroid_module(
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/johnrobbins/.vscode/extensions/ms-python.pylint-2023.10.1/bundled/libs/pylint/lint/pylinter.py", line 1069, in _check_astroid_module
    walker.walk(node)
  File "/Users/johnrobbins/.vscode/extensions/ms-python.pylint-2023.10.1/bundled/libs/pylint/utils/ast_walker.py", line 94, in walk
    self.walk(child)
  File "/Users/johnrobbins/.vscode/extensions/ms-python.pylint-2023.10.1/bundled/libs/pylint/utils/ast_walker.py", line 94, in walk
    self.walk(child)
  File "/Users/johnrobbins/.vscode/extensions/ms-python.pylint-2023.10.1/bundled/libs/pylint/utils/ast_walker.py", line 94, in walk
    self.walk(child)
  File "/Users/johnrobbins/.vscode/extensions/ms-python.pylint-2023.10.1/bundled/libs/pylint/utils/ast_walker.py", line 91, in walk
    callback(astroid)
  File "/Users/johnrobbins/.vscode/extensions/ms-python.pylint-2023.10.1/bundled/libs/pylint/checkers/variables.py", line 1642, in visit_name
    self._loopvar_name(node)
  File "/Users/johnrobbins/.vscode/extensions/ms-python.pylint-2023.10.1/bundled/libs/pylint/checkers/variables.py", line 2544, in _loopvar_name
    if astmts[i].statement().parent_of(stmt) and not utils.in_for_else_branch(
       ^^^^^^^^^^^^^^^^^^^^^
  File "/Users/johnrobbins/Code/tbp-venv/lib/python3.12/site-packages/astroid/nodes/node_ng.py", line 297, in statement
    return self.parent.statement()
           ^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/johnrobbins/Code/tbp-venv/lib/python3.12/site-packages/astroid/nodes/scoped_nodes/scoped_nodes.py", line 414, in statement
    raise StatementMissing(target=self)
astroid.exceptions.StatementMissing: Statement not found on <Module.arg l.0 at 0x103599640>

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/Users/johnrobbins/.vscode/extensions/ms-python.pylint-2023.10.1/bundled/libs/pylint/lint/pylinter.py", line 752, in _lint_files
    self._lint_file(fileitem, module, check_astroid_module)
  File "/Users/johnrobbins/.vscode/extensions/ms-python.pylint-2023.10.1/bundled/libs/pylint/lint/pylinter.py", line 790, in _lint_file
    raise astroid.AstroidError from e
astroid.exceptions.AstroidError

Expected behavior

No crash.

Pylint version

pylint 3.0.2
astroid 3.1.0
Python 3.12.1 (v3.12.1:2305ca5144, Dec  7 2023, 17:23:38) [Clang 13.0.0 (clang-1300.0.29.30)]

OS / Environment

darwin (Darwin)

Additional dependencies

I was running inside Visual Studio Code:
Version: 1.88.1 (Universal)
Commit: e170252f762678dec6ca2cc69aba1570769a5d39
Date: 2024-04-10T17:42:52.765Z
Electron: 28.2.8
ElectronBuildId: 27744544
Chromium: 120.0.6099.291
Node.js: 18.18.2
V8: 12.0.267.19-electron.0
OS: Darwin arm64 23.4.0

[jacobtylerwalls]

Thanks, but I can't reproduce on pylint 3.1.0. Notice that pylint 3.0.2 is not compatible with astroid 3.1.0. astroid should never be upgraded by itself.

[John-Robbins]

No worries! Thanks so much for the pointer about the mismatch between pylint and astroid. Looks like I have something screwed up between Python and my home-brew installs.