tinyDeepEqual.ts

const arrayEqual = (a: any[], b: any[]) => {
  if (a.length !== b.length) return false

  for (const index in a)
    if (!deepEqual(a[index], b[index])) {
      return false
    }

  return true
}

const objectEqual = (a: any, b: any) => {
  const propsA = Object.getOwnPropertyNames(a)
  const propsB = Object.getOwnPropertyNames(b)

  if (propsA.length !== propsB.length) {
    return false
  }

  for (const prop of propsA)
    if (
      !Object.prototype.hasOwnProperty.call(b, prop) ||
      !deepEqual(a[prop], b[prop])
    ) {
      return false
    }

  return true
}

export const deepEqual = (a: any, b: any) => {
  if (a === b) {
    return true
  }
  if (typeof a !== typeof b) {
    return false
  }
  if (a === null || b === null) {
    return false
  }
  if (Array.isArray(a)) {
    return arrayEqual(a, b)
  }
  if (typeof a === 'object') {
    return objectEqual(a, b)
  }
  return a.valueOf() === b.valueOf()
}

Nice