implement/test/test.implement.js

implement interface

"use strict"

const util = require("util")
const implement = require("implement")

// LIFO.
function Queue() {}
Queue.prototype = {
    offer: function (e) {},
    poll: function () {},
    peek: function () {}
}

// Queue backed by array.
function ArrayQueue() {}
ArrayQueue.prototype = {
    offer: function (e) {},
    poll: function () {},
    peek: function () {}
}
       
// FIFO.
function Stack() {}
Stack.prototype = {
    peek: function () {},
    pop: function () {},
    push: function () {}
}


describe("implement", function () {
    it("should not throw error when implementing interface", function (done) {
        implement(ArrayQueue, Queue) //ArrayQueue is a Queue
        done()
    })
    
    it("Should throw error when not implementing interface", function (done) {
        try {
            implement(Stack, Queue) // Stack is not the same as a Queue
        } catch (error) {
            done()        
        }
    })
    
    it("Should also work with objects", function (done) {
        implement(new ArrayQueue(), new Queue())
        done()
    })
})