stevedore test case for multiple driver entry_point failure

test_multi_driver.py

import unittest

import pkg_resources

import stevedore


class MockPkgResources(object):

    def iter_entry_points(self, namespace):
        ep1 = pkg_resources.EntryPoint.parse('backend = pkg1:driver')
        ep1.load = lambda : 'pkg1 backend'
        ep2 = pkg_resources.EntryPoint.parse('backend = pkg2:driver')
        ep2.load = lambda : 'pkg2 backend'
        return [ep1, ep2]


class TestMultiDriver(unittest.TestCase):

    def setUp(self):
        self._orig_pkg_resources = stevedore.extension.pkg_resources
        stevedore.extension.pkg_resources = MockPkgResources()

    def tearDown(self):
        pkg_resources == self._orig_pkg_resources

    def test_multiple_drivers(self):
        args = ('namespace', 'backend')
        try:
            stevedore.DriverManager(*args)
        except RuntimeError, e:
            self.assert_("Multiple %r drivers found" % args[0] in str(e), e)


if __name__ == "__main__":
    unittest.main()