Create and import helper functions in tests without creating packages in test directory using py.test

Question

Question

How can I import helper functions in test files without creating packages in the test directory?

Contex

Answer 1

While searching for a solution for this problem I came across this SO question and ended up adopting the same approach. Creating a helpers package, munging sys.path to make it importable and then just importing it...

This did not seem the best approach, so, I created pytest-helpers-namespace. This plugin allows you to register helper functions on your conftest.py:

import pytest

pytest_plugins = ['helpers_namespace']

@pytest.helpers.register
def my_custom_assert_helper(blah):
    assert blah

# One can even specify a custom name for the helper
@pytest.helpers.register(name='assertme')
def my_custom_assert_helper_2(blah):
    assert blah

# And even namespace helpers
@pytest.helpers.asserts.register(name='me')
def my_custom_assert_helper_3(blah):
    assert blah

And then, within a test case function body just use it like

def test_this():
    assert pytest.helpers.my_custom_assert_helper(blah) 

def test_this_2():
    assert pytest.helpers.assertme(blah)

def test_this_3():
    assert pytest.helpers.asserts.me(blah)

Its pretty simple and the documentation pretty small. Take a look and tell me if it addresses your problem too.