public void testDataDependance2() {
        try {
            TreeNode label = new TreeNode("label");
            TreeNode result = contains(new TreeNode(label), mkChain(new TreeNode[]{ label }));
            assertTrue(null, "Failed to locate the only node of a leaf!", 
                result != null
                && result.getData() != null 
                && ((result.getData()) instanceof TreeNode)
                && result.getBranch() != null
                && result.getBranch().length == 0);
        } catch(NotFound exn) {
            fail(exn, "You can not locate the only node of a leaf!");
        } catch(TreeException exn) {
            fail(exn, "An unexpected `TreeException` was thrown!");
        } catch(ClassCastException exn) {
            fail(exn, "Your code fails to deal with tree nodes that are **not** labeled with string data structures! Make sure that: \n* You have **not** written your answer assuming that `String`'s will be the only data type used\n* You have used the `correct` type of `equal`ity.");            
        } catch(Throwable exn) {
            fail(exn, "Unexpected exception thrown: " + exn.getClass().getName());
        } // end of try-catch
    } // end of method testDataDependance2