Crash on nodes.FunctionDef._proxied in numpy tests

[DanielNoord]

Bug description

pylint crashes on the following code:

import pytest
import warnings
import numpy as np


@pytest.mark.filterwarnings("error")
def test_getattr_warning():
    # issue gh-14735: make sure we clear only getattr errors, and let warnings
    # through
    class Wrapper:
        def __init__(self, array):
            self.array = array

        def __len__(self):
            return len(self.array)

        def __getitem__(self, item):
            return type(self)(self.array[item])

        def __getattr__(self, name):
            if name.startswith("__array_"):
                warnings.warn("object got converted", UserWarning, stacklevel=1)

            return getattr(self.array, name)

        def __repr__(self):
            return "<Wrapper({self.array})>".format(self=self)

    array = Wrapper(np.arange(10))
    with pytest.raises(UserWarning, match="object got converted"):
        np.asarray(array)


def test_array_called():
    class Wrapper:
        val = '0' * 100
        def __array__(self, result=None):
            return np.array([self.val], dtype=object)


    wrapped = Wrapper()
    arr = np.array(wrapped, dtype=str)
    assert arr.dtype == 'U100'
    assert arr[0] == Wrapper.val

Taken from:
https://github.com/numpy/numpy/blob/main/numpy/core/tests/test_protocols.py

Configuration

Configuration of `main`.

Command used

git clone https://github.com/numpy/numpy.git
pylint pylint numpy/core/tests/test_protocols.py

Or see GitHub Actions output here:
https://github.com/DanielNoord/pylint/runs/4082260843?check_suite_focus=true

Pylint output

************* Module numpy.core.tests.test_protocols
numpy/core/tests/test_protocols.py:1:0: C0114: Missing module docstring (missing-module-docstring)
numpy/core/tests/test_protocols.py:7:0: C0116: Missing function or method docstring (missing-function-docstring)
numpy/core/tests/test_protocols.py:10:4: C0115: Missing class docstring (missing-class-docstring)
Exception on node <FunctionDef.__len__ l.14 at 0x109d8a160> in file '/Users/daniel/DocumentenLaptop/Programming/Github/pylint/.pylint_primer_tests/numpy/numpy/numpy/core/tests/test_protocols.py'
Traceback (most recent call last):
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/inference_tip.py", line 28, in _inference_tip_cached
    result = _cache[func, node]
KeyError: (<function register_builtin_transform.<locals>._transform_wrapper at 0x109819e50>, <Call l.15 at 0x109d871c0>)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/utils/ast_walker.py", line 72, in walk
    callback(astroid)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/checkers/classes.py", line 2174, in visit_functiondef
    inferred = _safe_infer_call_result(node, node)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/checkers/classes.py", line 438, in _safe_infer_call_result
    value = next(inferit)
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/nodes/scoped_nodes.py", line 1804, in infer_call_result
    yield from returnnode.value.infer(context)
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/nodes/node_ng.py", line 113, in infer
    results = list(self._explicit_inference(self, context, **kwargs))
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/inference_tip.py", line 30, in _inference_tip_cached
    result = _cache[func, node] = list(func(*args, **kwargs))
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/brain/brain_builtin_inference.py", line 187, in _transform_wrapper
    result = transform(node, context=context)
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/brain/brain_builtin_inference.py", line 783, in infer_len
    return nodes.Const(helpers.object_len(argument_node, context=context))
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/helpers.py", line 262, in object_len
    and inferred_node._proxied == node_frame.parent
AttributeError: 'FunctionDef' object has no attribute '_proxied'
numpy/core/tests/test_protocols.py:1:0: F0001: Fatal error while checking 'numpy/core/tests/test_protocols.py'. Please open an issue in our bug tracker so we address this. There is a pre-filled template that you can use in '/Users/daniel/Library/Caches/pylint/pylint-crash-2021-11-02-18.txt'. (fatal)

-------------------------------------------------------------------
Your code has been rated at 6.25/10 (previous run: 10.00/10, -3.75)

Expected behavior

No error? I think?

This might also be due to this being code for tests which shouldn't be linted at all. I found this while working on the primer tests.

Pylint version

pylint 2.11.2-dev0
astroid 2.8.4
Python 3.9.6 (default, Aug  2 2021, 08:23:35) 
[Clang 12.0.5 (clang-1205.0.22.11)]

OS / Environment

No response

Additional dependencies

No response

[DanielNoord]

A minimal reproducible example is:

A directory that starts with numpy. Can be numpy2, numpy_2 or (seemingly) anything else with numpy at the start.

An empty numpy/__init__.py.

numpy/test.py with:

class MyClass:
    def __init__(self, array):
        self.array = array

    def __len__(self):
        return len(self.array)

Command:
pylint numpy/test.py

Crash:
pylint crashed with a AttributeError and with the following stacktrace:

Traceback (most recent call last):
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/inference_tip.py", line 28, in _inference_tip_cached
    result = _cache[func, node]
KeyError: (<function register_builtin_transform.<locals>._transform_wrapper at 0x10d3b2e50>, <Call l.6 at 0x10d9434f0>)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/lint/pylinter.py", line 1032, in _check_files
    self._check_file(get_ast, check_astroid_module, file)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/lint/pylinter.py", line 1067, in _check_file
    check_astroid_module(ast_node)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/lint/pylinter.py", line 1203, in check_astroid_module
    retval = self._check_astroid_module(
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/lint/pylinter.py", line 1250, in _check_astroid_module
    walker.walk(node)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/utils/ast_walker.py", line 75, in walk
    self.walk(child)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/utils/ast_walker.py", line 75, in walk
    self.walk(child)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/utils/ast_walker.py", line 72, in walk
    callback(astroid)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/checkers/classes.py", line 2174, in visit_functiondef
    inferred = _safe_infer_call_result(node, node)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/checkers/classes.py", line 438, in _safe_infer_call_result
    value = next(inferit)
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/nodes/scoped_nodes.py", line 1804, in infer_call_result
    yield from returnnode.value.infer(context)
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/nodes/node_ng.py", line 113, in infer
    results = list(self._explicit_inference(self, context, **kwargs))
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/inference_tip.py", line 30, in _inference_tip_cached
    result = _cache[func, node] = list(func(*args, **kwargs))
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/brain/brain_builtin_inference.py", line 187, in _transform_wrapper
    result = transform(node, context=context)
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/brain/brain_builtin_inference.py", line 783, in infer_len
    return nodes.Const(helpers.object_len(argument_node, context=context))
  File "/Users/daniel/.pyenv/versions/3.9.6/envs/pylint-3.9.6/lib/python3.9/site-packages/astroid/helpers.py", line 262, in object_len
    and inferred_node._proxied == node_frame.parent
AttributeError: 'FunctionDef' object has no attribute '_proxied'

I guess this has something to do with astroid's brain for numpy but I have no experience with brains so I don't know where to look to start fixing this.