pylint files gets imported when a file has the same name as one of pylint's files

[adamtheturtle]

An erroneous error occurs when a file is named "config.py".

Steps to reproduce

1. Create a structure as so:

> tree pylint-experiment/
pylint-experiment/
└── example
    ├── config.py
    └── foo.py

> cat pylint-experiment/example/foo.py
import config

print(config.VARIABLE)

> cat pylint-experiment/example/config.py
VARIABLE = 1

1. pylint --errors-only pylint-experiment/

Current behavior

************* Module some_dir.other
pylint-experiment/some_dir/other.py:3:6: E1101: Module 'config' has no 'VARIABLE' member (no-member)

Expected behavior

I expect to see:

************* Module example.foo
pylint-experiment/example/foo.py:1:0: E0401: Unable to import 'config' (import-error)

This is what happens if I rename config to bar and change import config to import bar.

pylint --version output

pylint 2.0.0.dev2
astroid 2.0.0.dev4
Python 3.7.0 (default, Jun 29 2018, 20:13:13) 
[Clang 9.1.0 (clang-902.0.39.2)]

[brycepg]

~This is working as intended since you are specifying a namespace/package to lint (since a folder is automatically a namespace package in python3). Python3 does not support relative imports for packages, so you see the error above.~

~You can see this in action with the python repl:~

cd pylint-experiment
python
> from example import foo
ModuleNotFoundError: No module named 'config'

~If you want to lint your script, foo.py, run pylint pylint-experiment/example/foo.py~

[adamtheturtle]

@brycepg I expected the import-error, as per "Expected behavior", but instead there is a no-member error, which happens when the file is named config.py.

[adamtheturtle]

That is, I'd expect the same error from both of these:

> pylint -E pylint-experiment-changed-names/
************* Module example.foo
pylint-experiment-changed-names/example/foo.py:1:0: E0401: Unable to import 'bar' (import-error)
> pylint -E pylint-experiment
************* Module example.foo
pylint-experiment/example/foo.py:3:6: E1101: Module 'config' has no 'VARIABLE' member (no-member)

Where pylint-experiment-changed-names/ is the same as the given example, but with config.py renamed to bar.py and the import in foo.py changed accordingly.

[brycepg]

Oh my bad, you're right. This also applies to explicit packages

[PCManticore]

So the super silly bug is that if your file is named config.py, then pylint imports its own config.py file:

In [3]: owner.file # where owner is the module that raised the error
Out[3]: '/Users/claudiu/projects/personal/pylint/pylint/config.py'

In [4]: owner.path
Out[4]: ['/Users/claudiu/projects/personal/pylint/pylint/config.py']

I bet the same happens for all the files in the pylint directory.

[nickroeker]

I'm experiencing what I think is a similar issue, tested with pylint version 1.9.3 and 2.0.1.

Repro Setup

Given the following setup,

config package:

$ tree config/
config/
└── subpackage
    └── __init__.py

message package:

$ tree message/
message/
└── subpackage
    └── __init__.py

very_custom_package package:

$ tree very_custom_package/
very_custom_package/
└── subpackage
    └── __init__.py

A test file for importing those packages:

$ tree tests/
tests/
├── __init__.py
└── test_packages.py

Contents of test file:

$ cat tests/test_packages.py 
"""Notice we get errors for `message` & `config`, but not `very_custom_package`."""
import config.subpackage
import message.subpackage
import very_custom_package.subpackage

print(config.subpackage.desc)
print(message.subpackage.desc)
print(very_custom_package.subpackage.desc)

Problem

If I run pylint tests/ (checked with both 1.9.3 and 2.0.1), I get erroneous complaints about the config and message packages, but not very_custom_package.

pyilnt 1.9.3 output:

$ pylint tests/
No config file found, using default configuration
************* Module tests.test_packages
E:  2, 0: No name 'subpackage' in module 'config' (no-name-in-module)
E:  3, 0: No name 'subpackage' in module 'message' (no-name-in-module)
E:  6, 6: Module 'config' has no 'subpackage' member (no-member)
E:  7, 6: Module 'message' has no 'subpackage' member (no-member)

pylint 2.0.1 output:

$ pylint tests/
************* Module tests.test_packages
tests/test_packages.py:2:0: E0611: No name 'subpackage' in module 'config' (no-name-in-module)
tests/test_packages.py:3:0: E0611: No name 'subpackage' in module 'message' (no-name-in-module)
tests/test_packages.py:6:6: E1101: Module 'config' has no 'subpackage' member (no-member)
tests/test_packages.py:7:6: E1101: Module 'message' has no 'subpackage' member (no-member)

Expected output

No errors for the message and config packages, like the very_custom_package package.

Things I've discovered

• Applies only to namespace packages as far as I can tell (perhaps even just _implicit_ namespace packages). Adding an __init__.py resolves the false-positive, but isn't desirable.
• Modifying the names slightly (e.g. config -> zconfig) results in the errors going away, so somehow the specific names matter & it's not related to the package being named with underscores.
• With other issues present as well, I've tested as far back as 1.7.0 and get the same sort of issue.