/usr/lib/nodejs/fbjs/lib/areEqual.js.flow is in node-fbjs 0.8.16-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 | /**
* Copyright (c) 2013-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @providesModule areEqual
* @flow
*/
const aStackPool = [];
const bStackPool = [];
/**
* Checks if two values are equal. Values may be primitives, arrays, or objects.
* Returns true if both arguments have the same keys and values.
*
* @see http://underscorejs.org
* @copyright 2009-2013 Jeremy Ashkenas, DocumentCloud Inc.
* @license MIT
*/
function areEqual(a: any, b: any): boolean {
const aStack = aStackPool.length ? aStackPool.pop() : [];
const bStack = bStackPool.length ? bStackPool.pop() : [];
const result = eq(a, b, aStack, bStack);
aStack.length = 0;
bStack.length = 0;
aStackPool.push(aStack);
bStackPool.push(bStack);
return result;
}
function eq(a: any, b: any, aStack: Array<any>, bStack: Array<any>): boolean {
if (a === b) {
// Identical objects are equal. `0 === -0`, but they aren't identical.
return a !== 0 || 1 / a == 1 / b;
}
if (a == null || b == null) {
// a or b can be `null` or `undefined`
return false;
}
if (typeof a != 'object' || typeof b != 'object') {
return false;
}
const objToStr = Object.prototype.toString;
const className = objToStr.call(a);
if (className != objToStr.call(b)) {
return false;
}
switch (className) {
case '[object String]':
return a == String(b);
case '[object Number]':
return isNaN(a) || isNaN(b) ? false : a == Number(b);
case '[object Date]':
case '[object Boolean]':
return +a == +b;
case '[object RegExp]':
return a.source == b.source && a.global == b.global && a.multiline == b.multiline && a.ignoreCase == b.ignoreCase;
}
// Assume equality for cyclic structures.
let length = aStack.length;
while (length--) {
if (aStack[length] == a) {
return bStack[length] == b;
}
}
aStack.push(a);
bStack.push(b);
let size = 0;
// Recursively compare objects and arrays.
if (className === '[object Array]') {
size = a.length;
if (size !== b.length) {
return false;
}
// Deep compare the contents, ignoring non-numeric properties.
while (size--) {
if (!eq(a[size], b[size], aStack, bStack)) {
return false;
}
}
} else {
if (a.constructor !== b.constructor) {
return false;
}
if (a.hasOwnProperty('valueOf') && b.hasOwnProperty('valueOf')) {
return a.valueOf() == b.valueOf();
}
const keys = Object.keys(a);
if (keys.length != Object.keys(b).length) {
return false;
}
for (let i = 0; i < keys.length; i++) {
if (!eq(a[keys[i]], b[keys[i]], aStack, bStack)) {
return false;
}
}
}
aStack.pop();
bStack.pop();
return true;
}
module.exports = areEqual;
|