@Test
public void copyMapping() {

    int[][] g1 = new int[][]{{1}, {0, 2}, {1, 3}, {2}};
    int[][] g2 = new int[][]{{1}, {0, 2}, {1, 3}, {2, 4}, {3, 5}, {4}};
    AbstractVFState state = create(g1, g2);
    state.m1[0] = 1;
    state.m1[1] = 2;
    state.m1[2] = 5;
    state.m1[3] = 6;
    assertThat(state.mapping(), is(state.m1));
    assertThat(state.mapping(), is(not(sameInstance(state.m1))));
}