Module Import Error running py.test with modules on Path

Question

I'm unable to import my module for testing in the way that I'd like. I'm running all of this in a virtualenv on 2.7.2

I have a directory structure like

/api
    /api
        __init__.py
        my_module.py
    /tests
        my_module_test.py

I have my PYTHONPATH set to /Path/api/. I CD into /Path/api and run the following

 py.test tests/my_module_test.py   

It does not work in the following case:

1. When I have the following at the top of my_module_test.py from api.my_module import my_function

It does work in the following case:

1. When I have the following at the top of my_module_test.py from my_module import my_function

Why am I not able to import my module as in case 1?

Answer 1

I use PYTHONPATH as

PYTHONPATH=`pwd` py.test tests/my_module_test.py

Answer 2

From the py.text document,you should install first.:

pip install -e .

Answer 3

I created this as an answer to your question and my own confusion. I hope it helps. Pay attention to PYTHONPATH in both the py.test command line and in the tox.ini.

The example project is here, and also below:

mymodule.py:

import boto3

def stuff():
    print "Yep!"

tests/text_syntax_errors.py:

import boto3
import mymodule


# Define a basic test that actually doesn't do much. 
# I just wanted more than zero tests
def test_one_equals_one():
    assert 1 == 1

tox.ini:

[tox]
skipsdist = True
envlist = py27

[flake8]
max-line-length = 119

[testenv]
deps= -r{toxinidir}/requirements.txt
commands=py.test
setenv =
    PYTHONPATH = {toxinidir}

requirements.txt:

boto3
pytest

From my README.md:

How-to run these examples

My initial motivation for testing my code was that I had misspelled an imported module in a script that I was writing for work.

If you edit mymodule.py and remove the b from "boto3" you will see the commands below fail. And this is a good thing. Likewise if you would like to see an actual test fail, simple edit tests/test_syntax_errors.py and change 1 == 1 to 1 == 0.

py.test

mbp0 pytest_test[master+*] $ PYTHONPATH=. py.test
========================== test session starts ==========================
platform darwin -- Python 2.7.11, pytest-2.9.2, py-1.4.31, pluggy-0.3.1
rootdir: /Users/jmacdonald/w/pytest_test, inifile:
collected 1 items

tests/test_syntax_errors.py .

======================= 1 passed in 0.11 seconds ========================
mbp0 pytest_test[master+*] $

tox

mbp0 pytest_test[master+*] $ tox
py27 installed: boto3==1.3.1,botocore==1.4.37,docutils==0.12,futures==3.0.5,jmespath==0.9.0,py==1.4.31,pytest==2.9.2,python-dateutil==2.5.3,six==1.10.0
py27 runtests: PYTHONHASHSEED='713732044'
py27 runtests: commands[0] | py.test
========================== test session starts ==========================
platform darwin -- Python 2.7.11, pytest-2.9.2, py-1.4.31, pluggy-0.3.1
rootdir: /Users/jmacdonald/w/pytest_test, inifile:
collected 1 items

tests/test_syntax_errors.py .

======================= 1 passed in 0.11 seconds ========================
________________________________ summary ________________________________
  py27: commands succeeded
  congratulations :)
mbp0 pytest_test[master+*] $