ace-diff/src/helpers/merge.js

A diff/merging wrapper for Ace Editor built on google-diff-match-patch

/**
 * Simple is object check.
 * @param item
 * @returns {boolean}
 */
function isObject(item) {
  return (item && typeof item === 'object' && !Array.isArray(item) && item !== null);
}


/**
* Deep merge two objects.
* @param target
* @param source
*/
module.exports = function merge(target, source) {
  if (isObject(target) && isObject(source)) {
    Object.keys(source).forEach((key) => {
      if (isObject(source[key])) {
        if (!target[key] || !isObject(target[key])) {
          target[key] = source[key];
        }
        merge(target[key], source[key]);
      } else {
        Object.assign(target, { [key]: source[key] });
      }
    });
  }
  return target;
};