const BinaryTree = require("./index"); describe("Binary Tree Preorder Traversal", () => { let btree; let preOrderTraversal; describe("Creates BTree", () => { btree = new BinaryTree([1, 2, 3, 4, 5, 6]); }); describe("BTree Traversals", () => { it("should compute the Preorder traversal for the above created binary tree", () => { preOrderTraversal = btree.preOrder(); expect(preOrderTraversal).toEqual([1, 2, 4, 5, 3, 6]); }); }); });