shallowEqual.js 654 B

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  1. function is(x, y) {
  2. if (x === y) {
  3. return x !== 0 || y !== 0 || 1 / x === 1 / y;
  4. } else {
  5. return x !== x && y !== y;
  6. }
  7. }
  8. export default function shallowEqual(objA, objB) {
  9. if (is(objA, objB)) return true;
  10. if (typeof objA !== 'object' || objA === null || typeof objB !== 'object' || objB === null) {
  11. return false;
  12. }
  13. var keysA = Object.keys(objA);
  14. var keysB = Object.keys(objB);
  15. if (keysA.length !== keysB.length) return false;
  16. for (var i = 0; i < keysA.length; i++) {
  17. if (!Object.prototype.hasOwnProperty.call(objB, keysA[i]) || !is(objA[keysA[i]], objB[keysA[i]])) {
  18. return false;
  19. }
  20. }
  21. return true;
  22. }