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.offset).toBe(0)
  11     expect(queue.maxSize).toBe(1)
  12     expect(queue.items).toStrictEqual([1])
  13     rtSize = queue.enqueue(2)
  14     expect(queue.size).toBe(2)
  15     expect(rtSize).toBe(queue.size)
  16     expect(queue.offset).toBe(0)
  17     expect(queue.maxSize).toBe(2)
  18     expect(queue.items).toStrictEqual([1, 2])
  19     rtSize = queue.enqueue(3)
  20     expect(queue.size).toBe(3)
  21     expect(rtSize).toBe(queue.size)
  22     expect(queue.offset).toBe(0)
  23     expect(queue.maxSize).toBe(3)
  24     expect(queue.items).toStrictEqual([1, 2, 3])
  25   })
  26
  27   it('Verify dequeue() behavior', () => {
  28     const queue = new Queue()
  29     queue.enqueue(1)
  30     queue.enqueue(2)
  31     queue.enqueue(3)
  32     let rtItem = queue.dequeue()
  33     expect(queue.size).toBe(2)
  34     expect(rtItem).toBe(1)
  35     expect(queue.offset).toBe(1)
  36     expect(queue.maxSize).toBe(3)
  37     expect(queue.items).toStrictEqual([1, 2, 3])
  38     rtItem = queue.dequeue()
  39     expect(queue.size).toBe(1)
  40     expect(rtItem).toBe(2)
  41     expect(queue.offset).toBe(0)
  42     expect(queue.maxSize).toBe(3)
  43     expect(queue.items).toStrictEqual([3])
  44     rtItem = queue.dequeue()
  45     expect(queue.size).toBe(0)
  46     expect(rtItem).toBe(3)
  47     expect(queue.offset).toBe(0)
  48     expect(queue.maxSize).toBe(3)
  49     expect(queue.items).toStrictEqual([])
  50   })
  51
  52   it('Verify clear() behavior', () => {
  53     const queue = new Queue()
  54     queue.enqueue(1)
  55     queue.enqueue(2)
  56     queue.enqueue(3)
  57     expect(queue.size).toBe(3)
  58     expect(queue.maxSize).toBe(3)
  59     queue.clear()
  60     expect(queue.size).toBe(0)
  61     expect(queue.maxSize).toBe(0)
  62     expect(queue.items).toStrictEqual([])
  63     expect(queue.offset).toBe(0)
  64   })
  65
  66   it('Verify iterator behavior', () => {
  67     const queue = new Queue()
  68     queue.enqueue(1)
  69     queue.enqueue(2)
  70     queue.enqueue(3)
  71     let i = 1
  72     for (const item of queue) {
  73       expect(item).toBe(i)
  74       ++i
  75     }
  76   })
  77 })