@Test
public void testGetOperatorCompletionsPredicate() throws Exception {

    when(conditionCol.getConstraintValueType()).thenReturn(BaseSingleFieldConstraint.TYPE_PREDICATE);
    Callback<String[]> callback = mock(Callback.class);
    page.getOperatorCompletions(pattern,
                                conditionCol,
                                callback);
    verify(callback).callback(new String[]{"==", "!=", "<", ">", "<=", ">=", "matches", "not matches", "soundslike", "not soundslike", "== null", "!= null"});
}