@Test
public void testDelegationConfigurationWithNullPrefix() {

	Configuration backingConf = new Configuration();
	backingConf.setValueInternal("test-key", "value");
	DelegatingConfiguration configuration = new DelegatingConfiguration(
			backingConf, null);
	Set<String> keySet = configuration.keySet();
	assertEquals(keySet, backingConf.keySet());
}