pelme / pytest-contextfixture

This repository is no longer maintained, please see the yield_fixture functionality in pytest: http://pytest.org/latest/yieldfixture.html

pytest-contextfixture makes it possible to define pytest fixtures as context managers.

A contextfixture works like a standard fixture, but it allows the definition to be written as a generator. This simplifies the teardown code and allows for other context managers to be used within a fixture.

Installation

pip install pytest-contextfixture

Usage

Consider this example, using the standard pytest.fixture:

import pytest

@pytest.fixture
def dependency(request)
    def teardown():
        # fixture teardown code goes here
    request.addfinalizer(teardown)

    return 1234

def test_foo(dependency):
    assert fn_under_test(dependency) == 'expected'

With pytest.contextfixture, this is equivalent:

import pytest

@pytest.contextfixture
def dependency(request):
    # fixture setup code goes here
    yield 1234
    # fixture teardown code goes here

def test_foo(dependency):
    assert fn_under_test(dependency) == 'expected'

While this is a slightly nicer syntax, when using other context managers to get a dependency for a fixture, this becomes more useful:

@pytest_contextfixture
def dependency(request):
    with setup_something():
        with setup_something_else() as d:
            yield d

def test_foo(dependency):
    assert fn_under_test(dependency) == 'expected'

test_foo will then run in the context of setup_something and setup_something_else.