Description
Bug report
This only happens with Python 3.11
The minimal reproducer I could come up with:
.
├── foo
│ └── __init__.py
└── tests
└── __init__.py
./foo/__init__.py
class Bar:
def baz(self):
..../tests/__init__.py
import unittest
import unittest.mock
import warnings
import mock # version 4.0.3
with warnings.catch_warnings():
warnings.simplefilter("ignore", ImportWarning)
# this import causes multiple import warnings
# warnings.simplefilter("once")
# <frozen importlib._bootstrap>:1049: ImportWarning: _SixMetaPathImporter.find_spec() not found; falling back to find_module()
# <frozen importlib._bootstrap>:673: ImportWarning: _SixMetaPathImporter.exec_module() not found; falling back to load_module()
# urllib3 vesrion 1.24.3
from urllib3.packages.six.moves.http_client import IncompleteRead
class TestFoo(unittest.TestCase):
def test_example(self):
# make import warnings raise to get a stack trace
warnings.simplefilter("error", ImportWarning)
with mock.patch("foo.Bar.baz"): # this is fine
...
# but this causes another import warning but only if IncompleteRead is
# imported above
with unittest.mock.patch("foo.Bar.baz"):
...Running this with python -m unittest tests, I get the following error
$ python -m unittest tests
E
======================================================================
ERROR: test_example (tests.TestFoo.test_example)
----------------------------------------------------------------------
Traceback (most recent call last):
File "<frozen importlib._bootstrap>", line 1074, in _find_spec
AttributeError: '_SixMetaPathImporter' object has no attribute 'find_spec'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File ".../example/tests/__init__.py", line 29, in test_example
with unittest.mock.patch("foo.Bar.baz"):
File ".../.pyenv/versions/3.11.0/lib/python3.11/unittest/mock.py", line 1411, in __enter__
self.target = self.getter()
^^^^^^^^^^^^^
File ".../.pyenv/versions/3.11.0/lib/python3.11/pkgutil.py", line 705, in resolve_name
mod = importlib.import_module(s)
^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".../.pyenv/versions/3.11.0/lib/python3.11/importlib/__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "<frozen importlib._bootstrap>", line 1206, in _gcd_import
File "<frozen importlib._bootstrap>", line 1178, in _find_and_load
File "<frozen importlib._bootstrap>", line 1140, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 1076, in _find_spec
File "<frozen importlib._bootstrap>", line 1049, in _find_spec_legacy
ImportWarning: _SixMetaPathImporter.find_spec() not found; falling back to find_module()
----------------------------------------------------------------------
Ran 1 test in 0.002s
FAILED (errors=1)
A clear and concise description of what the bug is.
Include a minimal, reproducible example (https://stackoverflow.com/help/minimal-reproducible-example), if possible.
Your environment
- CPython versions tested on:
$ python -VV
Python 3.11.0 (main, Nov 2 2022, 13:45:57) [GCC 11.3.0]
- Operating system and architecture:
Operating System: Linux Mint 21
Kernel: Linux 5.15.0-53-generic
Architecture: x86-64
In case you were wondering why I would import from urllib3.packages.six.moves.http_client import IncompleteRead: that's an indirect (over multiple hops) dependency of my actual test code. I found this line in urllib3 and figured I can reduce the reproducer for this weird issue with directly using that import.
Originally, if that matters, it's
from .packages.six.moves.http_client import (
IncompleteRead as httplib_IncompleteRead
)in urllib3/exceptions.py.
I'm aware that there is an external library involved, but seeing that the stack trace goes through some C extensions in importlib, I suspect this, while being triggered with the external lib, has it's root-cause somewhere else.