var assert = require('assert'); var intersperse = require('..'); describe('intersperse', function () { it("should return a new array for empty array", function () { var arr = []; var newArr = intersperse(arr); assert.deepEqual(newArr, []); assert.deepEqual(arr, []); assert.ok(newArr !== arr); }); it("should return a new array for single-item array", function () { var arr = [1]; var newArr = intersperse(arr); assert.deepEqual(newArr, [1]); assert.deepEqual(arr, [1]); assert.ok(newArr !== arr); }); it("should return a new interspersed array", function () { var arr = [1, 2, 3]; var newArr = intersperse(arr, 'a'); assert.deepEqual(newArr, [1, 'a', 2, 'a', 3]); assert.deepEqual(arr, [1, 2, 3]); }); });