This is a simple testing extension for distutils. The test class extends Command and can be used with the cmdclass argument. The setup function extends the default setup to accept a test_suite argument.

disttest.py

#	Copyright (c) 2014 Christian Schmitz <tynn.dev@gmail.com>
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"""
	This is the disttest python module. It is a fully functional replacement for
	the distutils.core module. Only the setup function is extended to support a
	test_suite keyword argument and to expose a test command.

	Just replace all imports from distutils.core with the respective imports
	from disttest.

	Pull the gist to include the module:
		git remote add disttest https://gist.github.com/9779576.git
		git pull disttest master
"""

import importlib, inspect, os.path, sys, unittest
from distutils.core import *


def _import_module (module) :
	if '/' in module :
		if os.path.isabs(module) :
			raise ImportError("Import by absolute filename is not supported")
		module = os.path.splitext(module)[0]
		if '.' in module :
			raise ImportError("Import by filenames with '.' is not supported")
		if module[-1] == '/' :
			module = module[:-1]
		module = module.replace(os.path.sep, '.')
	return importlib.import_module(module)


def _load_source_imp (name, pathname) :
	import imp
	imp.acquire_lock()
	try : return imp.load_compiled(name, pathname)
	except : return imp.load_source(name, pathname)
	finally : imp.release_lock()

def _load_source (path) :
	pathname = os.path.abspath(path)
	name = 'disttest._' + os.path.splitext(os.path.split(pathname)[1])[0]
	try :
		try : from importlib.machinery import SourceFileLoader
		except : return _load_source_imp(name, pathname)
		return SourceFileLoader(name, pathname).load_module()
	except : raise ImportError("No module named {}".format(path))


class test (Command) :

	description = "perform unit tests on extensions"
	user_options = [
		('test-suite=', 't', "test suite module to run"),
		('check', 'c', "run check command"),
		('skip-build', None, "skip the build steps"),
		('build-dir=', None, "build directory (implies --skip-build)"),
	]
	boolean_options = ['check', 'skip-build']

	def initialize_options (self) :
		self.build_dir = None
		self.check = None
		self.skip_build = None
		self.test_suite = None

	def finalize_options (self) :
		self.set_unittest_options()
		if not self.test_suite and hasattr(self.distribution, 'test_suite') :
			self.test_suite = getattr(self.distribution, 'test_suite')

		if self.build_dir :
			self.skip_build = True

		self.set_undefined_options('build', ('build_lib', 'build_dir'))
		self.set_undefined_options('install', ('skip_build', 'skip_build'))

	def set_unittest_options (self) :
		self.loader = unittest.defaultTestLoader
		self.suiteType = unittest.TestSuite

	def run (self) :
		if self.check :
			self.run_command('check')

		if not self.skip_build :
			self.run_command('build')

		if self.test_suite :
			self.run_tests()

	def run_tests (self) :
		sys.path.insert(0, self.build_dir)

		try : tests = self.suiteType(self.load_tests(self.test_suite))
		except ValueError :
			tests = self.suiteType()
			for _tests in self.test_suite :
				tests.addTest(self.load_tests(_tests))

		if not self.dry_run :
			unittest.TextTestRunner().run(tests)

		sys.path.remove(self.build_dir)

	def load_tests (self, tests) :
		if isinstance(tests, (unittest.TestCase, unittest.TestSuite)) :
			return tests

		if isinstance(tests, str) :
			try : tests = _import_module(tests)
			except : tests = _load_source(tests)

		if inspect.ismodule(tests) :
			return self.loader.loadTestsFromModule(tests)

		raise ValueError('Not a test suite: {}'.format(tests))


def _extend_setup (_setup = setup, _Distribution = Distribution) :
	"""
		Extend the default or any other compatible distutils setup function.
		The Distribution class used with setup must be supplied, if setup
		does not distutils.dist.Distribution as default.
	"""

	def setup (**attrs) :
		"""Extended setup function"""

		if 'cmdclass' not in attrs :
			attrs['cmdclass'] = {'test': test}
		elif 'test' not in attrs['cmdclass'] :
			attrs['cmdclass']['test'] = test

		if 'distclass' not in attrs :
			attrs['distclass'] = type('Distribution', (_Distribution, object), {"test_suite": None})
		elif not hasattr(attrs['distclass'], 'test_suite') :
			attrs['distclass'] = type('Distribution', (attrs['distclass'], object), {"test_suite": None})

		return _setup(**attrs)

	return setup


setup = _extend_setup()
setup_keywords = setup_keywords + ('test_suite',)