messages.ts

import { isArray, isObject } from './utils'

const isNotObjectOrIsArray = (val: unknown) => !isObject(val) || isArray(val)
// eslint-disable-next-line @typescript-eslint/no-explicit-any
export function deepCopy(src: any, des: any, isRetainExistMessage?: boolean): void {
  // src and des should both be objects, and none of them can be a array
  if (isNotObjectOrIsArray(src) || isNotObjectOrIsArray(des)) {
    throw new Error('Invalid value')
  }

  const stack = [{ src, des }]
  while (stack.length) {
    const { src, des } = stack.pop()!

    Object.keys(src).forEach(key => {
      if (isNotObjectOrIsArray(src[key]) || isNotObjectOrIsArray(des[key])) {
        // replace with src[key] when:
        // src[key] or des[key] is not an object, or
        // src[key] or des[key] is an array
        // if you need to keep the existing message on the i18n instance when merging, 
        // you do not need to perform the following replacement
        if (!isRetainExistMessage || typeof des[key] === 'undefined') {
          des[key] = src[key]
        }
      } else {
        // src[key] and des[key] are both objects, merge them
        stack.push({ src: src[key], des: des[key] })
      }
    })
  }
}