fix - Simple test fixtures

Author:	Zero Piraeus
Contact:	z@etiol.net

fix is a simple library to assist with the creation of fixtures for test functions, methods etc. It provides one decorator, with_fixture, which allows you to attach setup() and teardown() functions to the decorated callable, and access information defined in the fixture from within the test function.

fix was written for use with nose, but doesn't depend on it, and may also prove useful with other test frameworks.

Examples

Here's a basic example with setup but no teardown:

from fix import with_fixture

def setup_only(context):

    def setup():
        """Add something to the context."""
        assert context == {}
        context.squee = "kapow"

    return setup

@with_fixture(setup_only)
def case(context):
    assert context == {"squee": "kapow"}

... and here's a rather more involved one that creates some temporary files to work with, then deletes them during teardown:

import os
import shutil
import tempfile

from fix import with_fixture

def external(context, files=3):

    def setup():
        context.temp_dir = tempfile.mkdtemp()
        context.filenames = ["file_%03d" % i for i in range(files)]
        for filename in context.filenames:
            with open(os.path.join(context.temp_dir, filename), "w") as f:
                f.write("This is the file %r.\n" % filename)

    def teardown():
        shutil.rmtree(context.temp_dir)

    return setup, teardown

@with_fixture(external, files=5)
def check_files(context):
    present = 0
    absent = 0
    for filename in context.filenames:
        if os.path.exists(os.path.join(context.temp_dir, filename)):
            present += 1
        else:
            absent += 1
    return context.temp_dir, present, absent

temp_dir, present, absent = check_files()
assert not os.path.exists(temp_dir)
assert present == 5
assert absent == 0

Installation

This should do the trick:

pip install fix

Licence

fix is released under the GNU General Public License (version 3 or later), a copy of which is included with this distribution in the file COPYING.