@Test
public void isLeafReturnsFalseWhenDirectStaffAndStaffNotEmpty() {

    // given
    var node = new HierarchyTreeNode(userMock);
    var directStaffNode = new HierarchyTreeNode(otherUserMock);
    var staffNode = new HierarchyTreeNode(otherUserMock);
    node.directStaff = Collections.singletonList(directStaffNode);
    node.staff = Collections.singletonList(staffNode);
    // when / then
    assertThat(node.isLeaf()).isFalse();
}