         (Comment.self,  1),
         (Comment.self,  2),
         (More.self,     3),
+        (More.self,     3),
         (Comment.self,  1),
         (Comment.self,  2),
         (More.self,     3),

        (More.self,     3)
    ]
    
    /**
     test data
     comment
        comment
            more
        comment
            more
     comment
        comment
            more
     comment
        comment
            more
        comment
            more
     comment
        comment
            more
        comment
            more
        comment
            more
        comment
            more
    */
    func testListWhichHasSomeCommentsIncludingRepliesRecursively() {
        print("Test whether Parser can extend Comment objects that has some More objects as children.")

                        XCTFail("Error")
                    }
                    if let listing = array[1] as? Listing {
                        let incomming = listing.children
                            .flatMap({ $0 as? Comment })
                            .reduce([], combine: {
                                return $0 + extendAllRepliesAndDepth($1, depth: 1)
                            })
                        
                        incomming.forEach({
                            var b = ""
                            for _ in 0 ..< ($0.1 - 1) {
                                b += "  "
                            }
                            print("\(b)\($0.0.dynamicType) - \($0.0.id)")
                        })
                        
                        XCTAssert(gt_type.count == incomming.count, "list is mulformed.")
                        print(incomming)
                        print(gt_type)
                        print(gt_type.count)
                        for i in 0 ..< gt_type.count {
                            let (c, d) = gt_type[i]
                            XCTAssert(c == incomming[i].0.dynamicType, "data type error.")
                            XCTAssert(d == incomming[i].1, "element's depth is wrong.")
                        }
                    } else {
                        XCTFail("Error")
