Unfinished object comparison inspired by mist's attempt. https://github.com/Mistium/mist.js/blob/main/mist.js

object-compare.js

// latest edit: NaN checking
function ocom(a, b) {
  // Fast check.
  if (Object.is(a, b) || (a === b) || (Number.isNaN(a) && Number.isNaN(b))) return true;
  
  // The === would have caught it if they were the same.
  if (a instanceof Symbol || b instanceof Symbol) return false;
  // Custom matcher.
  if (a[ocom.matcher] && b[ocom.matcher]) return !!a[ocom.matcher](b);
  // Continue the === thing.
  if (typeof a !== 'object') return false;
  // Prototype checking.
  if (!Object.is(
    Object.getPrototypeOf(a),
    Object.getPrototypeOf(b),
  )) return false;
  // Checking the value.
  if (Object.is(Object.getPrototypeOf(a), Object)) {
    // fallthrough, this is just faster
  } else if (Array.isArray(a)) {
    if (a.length !== b.length) return false;
    // Check all the values.
    for (let i = a.length - 1; i > -1; --i) {
      if (!ocom(a[i], b[i])) return false;
    }
    return true;
  } else if (a instanceof Map) {
    // Pass the load to the array handler.
    return ocom(
      a.entries().toArray(),
      b.entries().toArray(),
    );
  } else if (a instanceof Set || a instanceof ocom.TypedArray) {
    return ocom(Array.from(a), Array.from(b));
  } else if (a instanceof DataView || a instanceof ArrayBuffer) {
    if (a instanceof DataView) {
      a = a.buffer;
      b = b.buffer;
    }
    return ocom(Array.from(new Uint8Array(a)), Array.from(new Uint8Array(b)));
  }
  const keysA = Object.getOwnPropertyNames(a).concat(Object.getOwnPropertySymbols(a));
  const keysB = Object.getOwnPropertyNames(b).concat(Object.getOwnPropertySymbols(b));
  if (keysA.length !== keysB.length) return false;
  for (let i = keysA.length - 1; i > -1; --i) {
    if (!ocom(keysA[i], keysB[i])) return false;
  }
  const valsA = Object.values(a);
  const valsB = Object.values(b);
  if (valsA.length !== valsB.length) return false;
  for (let i = valsA.length - 1; i > -1; --i) {
    if (!ocom(valsA[i], valsB[i])) return false;
  }
  return true;
}
ocom.TypedArray = Object.getPrototypeOf(Uint8Array);
ocom.matcher = Symbol('ObjectCompare.customMatch');

console.log(ocom({ x: 1 }, { x: 1 }));