Project Title

StackOverflow question study: Avoid package name collision in Python unittest

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.

To clone the project from Github, you can do:

git clone https://github.com/laurent-laporte-pro/stackoverflow-q52562454.git

Prerequisites

To see this study in action, you need Python (version 2 or 3), and (optionally) the PyTest framework.

Create and activate a virtualenv an run:

pip install pytest

Installing

This library in not available on PyPi, you need to install it from source.

pip install -e .

Running the samples

The purpose of this question is to understand the behavior of unittest –The standard module used to run unit tests– on a specific project configuration.

You can also try the behavior of PyTest –A third-party library– to compare the result.

To run unit tests with unittest:

python -m unittest discover tests

The problem is that we get an exception:


======================================================================
ERROR: package_1.test_module_1 (unittest.loader._FailedTest)
----------------------------------------------------------------------
ImportError: Failed to import test module: package_1.test_module_1
Traceback (most recent call last):
  ...
ModuleNotFoundError: No module named 'package_1.module_1'

To run unit tests with pytest:

pytest tests

With PyTest, we have the same kind of error:

ImportError while importing test module '.../test_module_1.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
tests/package_1/test_module_1.py:4: in <module>
    from package_1.module_1 import f
E   ModuleNotFoundError: No module named 'package_1.module_1'

This project was made to help understanding and reproducing the Original Poster's (OP) problem.

Possible solution

A solution is to turn the tests directory into a Python package by adding a __init__.py file. And run the unittest command by specifying the top level directory of the project:

python -m unittest discover tests -t .

The result is:


----------------------------------------------------------------------
Ran 1 test in 0.000s

OK

The problem is also resolved with PyTest:

pytest tests

The result is:


======================== test session starts ========================
platform darwin -- Python 3.6.1, pytest-3.8.1, py-1.6.0, pluggy-0.7.1
rootdir: /Users/laurentlaporte/workspace/stackoverflow-q52562454, ini
file:
collected 1 item                                                    

tests/package_1/test_module_1.py .                            [100%]

===================== 1 passed in 0.01 seconds ======================

Authors

Laurent LAPORTE - Initial work - GitHub profile

License

This project is licensed under the MIT License - see the LICENSE.md file for details

Acknowledgments

Maggyero Original Poster on StackOverflow.

laurent-laporte-pro / stackoverflow-q52562454