Function deepCopyDiff

src/common/object.js:114–121

(src, sample)

/** @return {?} `undefined` if equal */
export function deepCopyDiff(src, sample) {
  if (src === sample) return;
  if (!src || typeof src !== 'object') return src;
  if (!sample || typeof sample !== 'object') return deepCopy(src);
  deepDiff = false;
  src = (Array.isArray(src) ? deepCopyDiffArrays : deepCopyDiffObjects)(src, sample);
  if (deepDiff) return src;
}

function deepCopyDiffArrays(src, sample) {
  const res = [];