Skip to content
Permalink
9bfb9ba527
Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?
Go to file
 
 
Cannot retrieve contributors at this time
102 lines (90 sloc) 3.03 KB
var pSlice = Array.prototype.slice;
var Object_keys = typeof Object.keys === 'function'
? Object.keys
: function (obj) {
var keys = [];
for (var key in obj) keys.push(key);
return keys;
}
;
var deepEqual = module.exports = function (actual, expected) {
// enforce Object.is +0 !== -0
if (actual === 0 && expected === 0) {
return areZerosEqual(actual, expected);
// 7.1. All identical values are equivalent, as determined by ===.
} else if (actual === expected) {
return true;
} else if (actual instanceof Date && expected instanceof Date) {
return actual.getTime() === expected.getTime();
} else if (isNumberNaN(actual)) {
return isNumberNaN(expected);
// 7.3. Other pairs that do not both pass typeof value == 'object',
// equivalence is determined by ==.
} else if (typeof actual != 'object' && typeof expected != 'object') {
return actual == expected;
// 7.4. For all other Object pairs, including Array objects, equivalence is
// determined by having the same number of owned properties (as verified
// with Object.prototype.hasOwnProperty.call), the same set of keys
// (although not necessarily the same order), equivalent values for every
// corresponding key, and an identical 'prototype' property. Note: this
// accounts for both named and indexed properties on Arrays.
} else {
return objEquiv(actual, expected);
}
};
function isUndefinedOrNull(value) {
return value === null || value === undefined;
}
function isArguments(object) {
return Object.prototype.toString.call(object) == '[object Arguments]';
}
function isNumberNaN(value) {
// NaN === NaN -> false
return typeof value == 'number' && value !== value;
}
function areZerosEqual(zeroA, zeroB) {
// (1 / +0|0) -> Infinity, but (1 / -0) -> -Infinity and (Infinity !== -Infinity)
return (1 / zeroA) === (1 / zeroB);
}
function objEquiv(a, b) {
if (isUndefinedOrNull(a) || isUndefinedOrNull(b))
return false;
// an identical 'prototype' property.
if (a.prototype !== b.prototype) return false;
//~~~I've managed to break Object.keys through screwy arguments passing.
// Converting to array solves the problem.
if (isArguments(a)) {
if (!isArguments(b)) {
return false;
}
a = pSlice.call(a);
b = pSlice.call(b);
return deepEqual(a, b);
}
try {
var ka = Object_keys(a),
kb = Object_keys(b),
key, i;
} catch (e) {//happens when one is a string literal and the other isn't
return false;
}
// having the same number of owned properties (keys incorporates
// hasOwnProperty)
if (ka.length != kb.length)
return false;
//the same set of keys (although not necessarily the same order),
ka.sort();
kb.sort();
//~~~cheap key test
for (i = ka.length - 1; i >= 0; i--) {
if (ka[i] != kb[i])
return false;
}
//equivalent values for every corresponding key, and
//~~~possibly expensive deep test
for (i = ka.length - 1; i >= 0; i--) {
key = ka[i];
if (!deepEqual(a[key], b[key])) return false;
}
return true;
}