deepEqual.js

deepEqual.js

function deepEqual(a, b) {
  // Handle edge cases and primitives using Object.is
  if (Object.is(a, b)) return true;

  // Handle arrays
  const isArray = Array.isArray(a) && Array.isArray(b);
  const isTypedArray = ArrayBuffer.isView(a) && ArrayBuffer.isView(b);
  if (isArray || isTypedArray) {
    if (isTypedArray) {
      // Check if both are of the same type
      if (Object.getPrototypeOf(a) !== Object.getPrototypeOf(b)) return false;
    }

    if (a.length !== b.length) return false;
    for (let i = 0; i < a.length; i++) {
      if (isTypedArray) {
        if (a[i] !== b[i]) return false;
      } else if (!deepEqual(a[i], b[i])) return false;
    }
    return true;
  }

  // Handle maps
  if (a instanceof Map && b instanceof Map) {
    if (a.size !== b.size) return false;
    for (const key of a.keys()) {
      if (!b.has(key)) return false;
    }
    for (const [key, value] of a) {
      if (!deepEqual(value, b.get(key))) return false;
    }
    return true;
  }

  // Handle sets
  if (a instanceof Set && b instanceof Set) {
    if (a.size !== b.size) return false;
    for (const value of a) {
      if (!b.has(value)) return false;
    }
    return true;
  }

  // Handle Date objects
  if (a instanceof Date && b instanceof Date) {
    return a.getTime() === b.getTime();
  }

  // Handle RegExp objects
  if (a instanceof RegExp && b instanceof RegExp) {
    return a.source === b.source && a.flags === b.flags;
  }

  // Handle objects
  if (a instanceof Object && b instanceof Object) {
    const keysA = Object.keys(a);
    const keysB = Object.keys(b);
    if (!deepEqual(keysA, keysB)) return false;
    for (let key of keysA) {
      if (!deepEqual(a[key], b[key])) return false;
    }
    return true;
  }

  // If none of the above checks pass, the objects are not deep equal
  return false;
}