How to import a class from unittest in python?

Question

I have a very basic question about Python and unittest.

I have a directory structure like this.

Project
   |
   |-lib
      |
      |-__init__.py
      |-class.py
   |
   |-tests
      |
      |-__init__.py
      |-test_class.py

Now this is my content of test_class.py. If I import the lib.class from the root folder it's working fine. But if I import the file from somewhere else it's not working.

import unittest
from lib.class import Class

class TestClass(unittest.TestCase):
    def testClass(self):
            // do some test

def main():
    unittest.main()

if __name__ == '__main__':
    main()

When I run the test I got this error

Traceback (most recent call last):
  File "tests/test_class.py", line 2, in 
    from lib.class import Class
ImportError: No module named lib.class

Not sure how do I import the file from another folder that's not the root folder.

Answer 1

The better solution is to create a virtualenv and install the project in developer mode. This allows you to modify and execute code without having to re-install it.

virtualenv venv
source venv/bin/activate
pip install -e .

Inside the tests you would now simply include the fqdn.

from project.lib.class import Class

Keep in mind that you will need to use setuptools to properly define the project.

Answer 2

Modify sys.path to include the Project directory

import sys
sys.path.append('/path/to/Project')

On Linux, you could do

import sys, os
sys.path.append(os.path.abspath(sys.path[0]) + '/../')

and that should include the directory above the running Python testing script, which is the Project folder