loose-equal.spec.js 7.86 KB
import { looseEqual } from './loose-equal'

describe('utils/looseEqual', () => {
  it('compares booleans correctly', () => {
    expect(looseEqual(true, true)).toBe(true)
    expect(looseEqual(false, false)).toBe(true)
    expect(looseEqual(true, false)).toBe(false)
    expect(looseEqual(true, true)).toBe(true)
    expect(looseEqual(true, 1)).toBe(false)
    expect(looseEqual(false, 0)).toBe(false)
  })

  it('compares strings correctly', () => {
    const text = 'Lorem ipsum'
    const number = 1
    const bool = true

    expect(looseEqual(text, text)).toBe(true)
    expect(looseEqual(text, text.slice(0, -1))).toBe(false)
    expect(looseEqual(String(number), number)).toBe(true)
    expect(looseEqual(String(bool), bool)).toBe(true)
  })

  it('compares numbers correctly', () => {
    const number = 100
    const decimal = 2.5
    const multiplier = 1.0000001

    expect(looseEqual(number, number)).toBe(true)
    expect(looseEqual(number, number - 1)).toBe(false)
    expect(looseEqual(decimal, decimal)).toBe(true)
    expect(looseEqual(decimal, decimal * multiplier)).toBe(false)
    expect(looseEqual(number, number * multiplier)).toBe(false)
    expect(looseEqual(multiplier, multiplier)).toBe(true)
  })

  it('compares dates correctly', () => {
    const date1 = new Date(2020, 1, 2, 3, 4, 5, 6)
    const date2 = new Date(2020, 1, 2, 3, 4, 5, 6)
    const date3 = new Date(2020, 1, 2, 3, 4, 5, 7)
    const date4 = new Date(2219, 1, 2, 3, 4, 5, 6)

    // Identical date object references
    expect(looseEqual(date1, date1)).toBe(true)
    // Different date references with identical values
    expect(looseEqual(date1, date2)).toBe(true)
    // Dates with slightly different time (ms)
    expect(looseEqual(date1, date3)).toBe(false)
    // Dates with different year
    expect(looseEqual(date1, date4)).toBe(false)
  })

  it('compares files correctly', () => {
    const date1 = new Date(2020, 1, 2, 3, 4, 5, 6)
    const date2 = new Date(2020, 1, 2, 3, 4, 5, 7)
    const file1 = new File([''], 'filename.txt', { type: 'text/plain', lastModified: date1 })
    const file2 = new File([''], 'filename.txt', { type: 'text/plain', lastModified: date1 })
    const file3 = new File([''], 'filename.txt', { type: 'text/plain', lastModified: date2 })
    const file4 = new File([''], 'filename.csv', { type: 'text/csv', lastModified: date1 })
    const file5 = new File(['abcdef'], 'filename.txt', { type: 'text/plain', lastModified: date1 })
    const file6 = new File(['12345'], 'filename.txt', { type: 'text/plain', lastModified: date1 })

    // Identical file object references
    expect(looseEqual(file1, file1)).toBe(true)
    // Different file references with identical values
    expect(looseEqual(file1, file2)).toBe(true)
    // Files with slightly different dates
    expect(looseEqual(file1, file3)).toBe(false)
    // Two different file types
    expect(looseEqual(file1, file4)).toBe(false)
    // Two files with same name, modified date, but different content
    expect(looseEqual(file5, file6)).toBe(false)
  })

  it('compares arrays correctly', () => {
    const arr1 = [1, 2, 3, 4]
    const arr2 = [1, 2, 3, '4']
    const arr3 = [1, 2, 3, 4, 5]
    const arr4 = [1, 2, 3, 4, { a: 5 }]

    // Identical array references
    expect(looseEqual(arr1, arr1)).toBe(true)
    // Different array references with identical values
    expect(looseEqual(arr1, arr1.slice())).toBe(true)
    expect(looseEqual(arr4, arr4.slice())).toBe(true)
    // Array with one value different (loose)
    expect(looseEqual(arr1, arr2)).toBe(true)
    // Array with one value different
    expect(looseEqual(arr3, arr4)).toBe(false)
    // Arrays with different lengths
    expect(looseEqual(arr1, arr3)).toBe(false)
    // Arrays with values in different order
    expect(looseEqual(arr1, arr1.slice().reverse())).toBe(false)
  })

  it('compares RegExp correctly', () => {
    const rx1 = /^foo$/
    const rx2 = /^foo$/
    const rx3 = /^bar$/
    const rx4 = /^bar$/i

    // Identical regex references
    expect(looseEqual(rx1, rx1)).toBe(true)
    // Different regex references with identical values
    expect(looseEqual(rx1, rx2)).toBe(true)
    // Different regex
    expect(looseEqual(rx1, rx3)).toBe(false)
    // Same regex with different options
    expect(looseEqual(rx3, rx4)).toBe(false)
  })

  it('compares objects correctly', () => {
    const obj1 = { foo: 'bar' }
    const obj2 = { foo: 'bar1' }
    const obj3 = { a: 1, b: 2, c: 3 }
    const obj4 = { b: 2, c: 3, a: 1 }
    const obj5 = { ...obj4, z: 999 }
    const nestedObj1 = { ...obj1, bar: [{ ...obj1 }, { ...obj1 }] }
    const nestedObj2 = { ...obj1, bar: [{ ...obj1 }, { ...obj2 }] }

    // Identical object references
    expect(looseEqual(obj1, obj1)).toBe(true)
    // Two objects with identical keys/values
    expect(looseEqual(obj1, { ...obj1 })).toBe(true)
    // Different key values
    expect(looseEqual(obj1, obj2)).toBe(false)
    // Keys in different orders
    expect(looseEqual(obj3, obj4)).toBe(true)
    // One object has additional key
    expect(looseEqual(obj4, obj5)).toBe(false)
    // Identical object references with nested array
    expect(looseEqual(nestedObj1, nestedObj1)).toBe(true)
    // Identical object definitions with nested array
    expect(looseEqual(nestedObj1, { ...nestedObj1 })).toBe(true)
    // Object definitions with nested array (which has different order)
    expect(looseEqual(nestedObj1, nestedObj2)).toBe(false)
  })

  it('compares different types correctly', () => {
    const obj1 = {}
    const obj2 = { a: 1 }
    const obj3 = { 0: 0, 1: 1, 2: 2 }
    const arr1 = []
    const arr2 = [1]
    const arr3 = [0, 1, 2]
    const date1 = new Date(2020, 1, 2, 3, 4, 5, 6)
    const file1 = new File([''], 'filename.txt', { type: 'text/plain', lastModified: date1 })

    expect(looseEqual(123, '123')).toBe(true)
    expect(looseEqual(123, new Date(123))).toBe(false)
    expect(looseEqual(`123`, new Date(123))).toBe(false)
    expect(looseEqual([1, 2, 3], '1,2,3')).toBe(false)
    expect(looseEqual(obj1, arr1)).toBe(false)
    expect(looseEqual(obj2, arr2)).toBe(false)
    expect(looseEqual(obj1, '[object Object]')).toBe(false)
    expect(looseEqual(arr1, '[object Array]')).toBe(false)
    expect(looseEqual(obj1, date1)).toBe(false)
    expect(looseEqual(obj2, date1)).toBe(false)
    expect(looseEqual(arr1, date1)).toBe(false)
    expect(looseEqual(arr2, date1)).toBe(false)
    expect(looseEqual(obj2, file1)).toBe(false)
    expect(looseEqual(arr2, file1)).toBe(false)
    expect(looseEqual(date1, file1)).toBe(false)
    // Special case where an object's keys are the same as keys (indexes) of an array
    expect(looseEqual(obj3, arr3)).toBe(false)
  })

  it('compares null and undefined values correctly', () => {
    expect(looseEqual(null, null)).toBe(true)
    expect(looseEqual(undefined, undefined)).toBe(true)
    // eslint-disable-next-line no-void
    expect(looseEqual(void 0, undefined)).toBe(true)
    expect(looseEqual(null, undefined)).toBe(false)
    // eslint-disable-next-line no-void
    expect(looseEqual(null, void 0)).toBe(false)
    expect(looseEqual(null, '')).toBe(false)
    expect(looseEqual(null, false)).toBe(false)
    expect(looseEqual(undefined, false)).toBe(false)
  })

  it('compares sparse arrays correctly', () => {
    // The following arrays all have a length of 3
    // But the first two are "sparse"
    const arr1 = []
    arr1[2] = true
    const arr2 = []
    arr2[2] = true
    const arr3 = [false, false, true]
    const arr4 = [undefined, undefined, true]
    // This one is also sparse (missing index 1)
    const arr5 = []
    arr5[0] = arr5[2] = true

    expect(looseEqual(arr1, arr2)).toBe(true)
    expect(looseEqual(arr2, arr1)).toBe(true)
    expect(looseEqual(arr1, arr3)).toBe(false)
    expect(looseEqual(arr3, arr1)).toBe(false)
    expect(looseEqual(arr1, arr4)).toBe(true)
    expect(looseEqual(arr4, arr1)).toBe(true)
    expect(looseEqual(arr1, arr5)).toBe(false)
    expect(looseEqual(arr5, arr1)).toBe(false)
  })
})