65 lines
1.7 KiB
JavaScript
65 lines
1.7 KiB
JavaScript
/**
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* Copyright (c) 2015-present, Facebook, Inc.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*
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* @providesModule deepDiffer
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* @flow
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*/
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'use strict';
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/*
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* @returns {bool} true if different, false if equal
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*/
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var deepDiffer = function(one: any, two: any): bool {
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if (one === two) {
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// Short circuit on identical object references instead of traversing them.
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return false;
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}
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if ((typeof one === 'function') && (typeof two === 'function')) {
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// We consider all functions equal
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return false;
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}
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if ((typeof one !== 'object') || (one === null)) {
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// Primitives can be directly compared
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return one !== two;
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}
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if ((typeof two !== 'object') || (two === null)) {
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// We know they are different because the previous case would have triggered
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// otherwise.
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return true;
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}
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if (one.constructor !== two.constructor) {
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return true;
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}
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if (Array.isArray(one)) {
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// We know two is also an array because the constructors are equal
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var len = one.length;
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if (two.length !== len) {
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return true;
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}
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for (var ii = 0; ii < len; ii++) {
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if (deepDiffer(one[ii], two[ii])) {
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return true;
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}
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}
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} else {
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for (var key in one) {
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if (deepDiffer(one[key], two[key])) {
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return true;
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}
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}
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for (var twoKey in two) {
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// The only case we haven't checked yet is keys that are in two but aren't
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// in one, which means they are different.
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if (one[twoKey] === undefined && two[twoKey] !== undefined) {
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return true;
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}
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}
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}
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return false;
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};
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module.exports = deepDiffer;
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