@Test
public void shouldReturnListOfChildren() {

    parent = new AstNode("parent");
    AstNode child1 = new AstNode(parent, "childA");
    AstNode child2 = new AstNode(parent, "childB");
    AstNode child3 = new AstNode(parent, "childC");
    List<AstNode> children = parent.getChildren();
    assertThat(children.get(0), is(sameInstance(child1)));
    assertThat(children.get(1), is(sameInstance(child2)));
    assertThat(children.get(2), is(sameInstance(child3)));
    assertThat(children.size(), is(3));
}