def test_subproject_system_option(self):
        """Test that subproject system options get their default value from the global
           option (e.g. "sub:b_lto" can be initialized from "b_lto")."""
        optstore = OptionStore(False)
        name = 'someoption'
        default_value = 'somevalue'
        new_value = 'new_value'
        k = OptionKey(name)
        subk = k.evolve(subproject='sub')
        optstore.initialize_from_top_level_project_call({}, {}, {OptionKey(name): new_value})
        vo = UserStringOption(k.name, 'An option of some sort', default_value)
        optstore.add_system_option(subk, vo)
        self.assertEqual(optstore.get_value_for(subk), new_value)
Test that subproject system options get their default value from the global
           option (e.g. "sub:b_lto" can be initialized from "b_lto").
unittests/optiontests.py