tests/queue.test.js

   1 const { expect } = require('expect')
   2 const { Queue } = require('../lib/queue')
   3
   4 describe('Queue test suite', () => {
   5   it('Verify enqueue() behavior', () => {
   6     const queue = new Queue()
   7     let rtSize = queue.enqueue(1)
   8     expect(queue.size).toBe(1)
   9     expect(rtSize).toBe(queue.size)
  10     expect(queue.head).toBe(0)
  11     expect(queue.tail).toBe(1)
  12     expect(queue.max).toBe(1)
  13     expect(queue.items).toStrictEqual({ 0: 1 })
  14     rtSize = queue.enqueue(2)
  15     expect(queue.size).toBe(2)
  16     expect(rtSize).toBe(queue.size)
  17     expect(queue.head).toBe(0)
  18     expect(queue.tail).toBe(2)
  19     expect(queue.max).toBe(2)
  20     expect(queue.items).toStrictEqual({ 0: 1, 1: 2 })
  21     rtSize = queue.enqueue(3)
  22     expect(queue.size).toBe(3)
  23     expect(rtSize).toBe(queue.size)
  24     expect(queue.head).toBe(0)
  25     expect(queue.tail).toBe(3)
  26     expect(queue.max).toBe(3)
  27     expect(queue.items).toStrictEqual({ 0: 1, 1: 2, 2: 3 })
  28   })
  29
  30   it('Verify dequeue() behavior', () => {
  31     const queue = new Queue()
  32     queue.enqueue(1)
  33     queue.enqueue(2)
  34     queue.enqueue(3)
  35     let rtItem = queue.dequeue()
  36     expect(queue.size).toBe(2)
  37     expect(rtItem).toBe(1)
  38     expect(queue.head).toBe(1)
  39     expect(queue.tail).toBe(3)
  40     expect(queue.max).toBe(3)
  41     expect(queue.items).toStrictEqual({ 1: 2, 2: 3 })
  42     rtItem = queue.dequeue()
  43     expect(queue.size).toBe(1)
  44     expect(rtItem).toBe(2)
  45     expect(queue.head).toBe(2)
  46     expect(queue.tail).toBe(3)
  47     expect(queue.max).toBe(3)
  48     expect(queue.items).toStrictEqual({ 2: 3 })
  49     rtItem = queue.dequeue()
  50     expect(queue.size).toBe(0)
  51     expect(rtItem).toBe(3)
  52     expect(queue.head).toBe(0)
  53     expect(queue.tail).toBe(0)
  54     expect(queue.max).toBe(3)
  55     expect(queue.items).toStrictEqual({})
  56   })
  57 })