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ImportWarning when importing a PEP 420 namespace package

See original GitHub issue

The pkg_resources code is raising an ImportWarning when it attempts to import a PEP 420 implicit namespace package:

ImportError: Failed to import test module: test.test_methods
Traceback (most recent call last):
  File "/usr/lib/python3.5/unittest/loader.py", line 428, in _find_test_path
    module = self._get_module_from_name(name)
  File "/usr/lib/python3.5/unittest/loader.py", line 369, in _get_module_from_name
    __import__(name)
  File "/home/bignose/Projects/debian/dput/trunk/test/test_methods.py", line 26, in <module>
    import testscenarios
  File "/usr/lib/python3/dist-packages/testscenarios/__init__.py", line 57, in <module>
    from testscenarios.scenarios import (
  File "/usr/lib/python3/dist-packages/testscenarios/scenarios.py", line 34, in <module>
    from testtools import iterate_tests
  File "/usr/lib/python3/dist-packages/testtools/__init__.py", line 124, in <module>
    from pbr.version import VersionInfo
  File "/usr/lib/python3/dist-packages/pbr/version.py", line 25, in <module>
    import pkg_resources
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 3037, in <module>
    @_call_aside
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 3021, in _call_aside
    f(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 3065, in _initialize_master_working_set
    for dist in working_set
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 3065, in <genexpr>
    for dist in working_set
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2595, in activate
    declare_namespace(pkg)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2163, in declare_namespace
    _handle_ns(packageName, path_item)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2083, in _handle_ns
    loader = importer.find_module(packageName)
  File "<frozen importlib._bootstrap_external>", line 445, in _find_module_shim
ImportWarning: Not importing directory /usr/lib/python3/dist-packages/keyrings: missing __init__

(To reproduce this, enable the -W error option to python3. I did this to try to catch warnings in my code, assuming that libraries would not cause them 😕)

The “Not importing directory […] missing init” contradicts the explicit specification from PEP 420:

Namespace packages [as specified in this PEP] cannot contain an init.py .

Issue Analytics

State:
Created 6 years ago
Reactions:1
Comments:19 (13 by maintainers)

Top GitHub Comments

3reactions

jdufresnecommented, Aug 1, 2017

I’m seeing this as well. It is causing loads of noise in my logs when Python warnings are enabled. Here is a minimal bash script to demonstrate the error:

#!/bin/bash

rm -rf venv
python3 -m venv venv
venv/bin/pip install sphinxcontrib-websupport
venv/bin/python -Werror -c 'import pkg_resources'

Actual output:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/jon/warning-test/venv/lib64/python3.5/site-packages/pkg_resources/__init__.py", line 2958, in <module>
    @_call_aside
  File "/home/jon/warning-test/venv/lib64/python3.5/site-packages/pkg_resources/__init__.py", line 2944, in _call_aside
    f(*args, **kwargs)
  File "/home/jon/warning-test/venv/lib64/python3.5/site-packages/pkg_resources/__init__.py", line 2985, in _initialize_master_working_set
    dist.activate(replace=False)
  File "/home/jon/warning-test/venv/lib64/python3.5/site-packages/pkg_resources/__init__.py", line 2521, in activate
    declare_namespace(pkg)
  File "/home/jon/warning-test/venv/lib64/python3.5/site-packages/pkg_resources/__init__.py", line 2103, in declare_namespace
    _handle_ns(packageName, path_item)
  File "/home/jon/warning-test/venv/lib64/python3.5/site-packages/pkg_resources/__init__.py", line 2037, in _handle_ns
    loader = importer.find_module(packageName)
  File "<frozen importlib._bootstrap_external>", line 445, in _find_module_shim
ImportWarning: Not importing directory /home/jon/warning-test/venv/lib64/python3.5/site-packages/sphinxcontrib: missing __init__

1reaction

jaracocommented, Sep 14, 2018

I tried replicating the issue on Python 3.6 but couldn’t

Glad I pasted my exact commands, because I started replicating it on my local workstation and couldn’t figure out what I’d done wrong. I see now I neglected to include the important -W error when I tried to replicate the issue above.

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