@synergy-design-system/components/code-quality/html-validate/scripts/mergeDeep.js

This package provides the base of the Synergy Design System as native web components. It uses [lit](https://www.lit.dev) and parts of [shoelace](https://shoelace.style/). Synergy officially supports the latest two versions of all major browsers (as define

/**
 * Creates a deep merged clone of the given objects.
 * @param  {...any} objects The objects to merge
 * @returns {object} The new object
 */
export const mergeDeep = (...objects) => {
  const isObject = obj => obj && typeof obj === 'object';

  return objects.reduce((acc, obj) => {
    Object.keys(obj).forEach(key => {
      const accValue = acc[key];
      const objValue = obj[key];

      if (Array.isArray(objValue)) {
        acc[key] = Array.isArray(accValue) ? [...accValue, ...objValue] : [...objValue];
      } else if (isObject(objValue)) {
        acc[key] = isObject(accValue) ? mergeDeep(accValue, objValue) : { ...objValue };
      } else {
        acc[key] = objValue;
      }
    });

    return acc;
  }, {});
};