'Make sure the tests do not match on magic values,
no double underscored values, like \'__dict__\',
and no instance values, like \'()\'.'

def test_no_magic_values(self, testdir):

    p = testdir.makepyfile('\n                                                def    test_one():    assert    1\n                                ')
    def assert_test_is_not_selected(keyword):
        reprec = testdir.inline_run('-k', keyword, p)
        (passed, skipped, failed) = reprec.countoutcomes()
        dlist = reprec.getcalls('pytest_deselected')
        assert (((passed + skipped) + failed) == 0)
        deselected_tests = dlist[0].items
        assert (len(deselected_tests) == 1)
    assert_test_is_not_selected('__')
    assert_test_is_not_selected('()')
