target.setRoles( Arrays.asList( "first", "second", "third" ) );
        Contributor source = new Contributor();
        source.setRoles( Arrays.asList( "first", "second", "third" ) );

        modelMerger.mergeContributor_Roles( target, source, true, null );

        assertThat( target.getRoles(), contains( "first", "second", "third" ) );
    }

    @Test
    public void mergeUrl()
    {