public void testSearchByKeyAndValueReturnsResultsForBlankValues() throws Exception {
        final DefaultGroupProvider provider = new DefaultGroupProvider();
        provider.createGroup("Test Group A").shareWithNobody();
        provider.createGroup("Test Group B").shareWithNobody();
        final Collection<String> result = provider.search(Group.SHARED_ROSTER_GROUP_LIST_PROPERTY_KEY, "");
        assertEquals(2, result.size());
        assertTrue(result.contains("Test Group A"));
        assertTrue(result.contains("Test Group B"));
    }
Verifies that a {@link AbstractGroupProvider#getVisibleGroupNames(String)} returns a group shared with itself
xmppserver/src/test/java/org/jivesoftware/openfire/group/AbstractGroupProviderTest.java