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@stamat
Last active Aug 19, 2016
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Compare objects and arrays...
//Returns the object's class, Array, Date, RegExp, Object are of interest to us
var getClass = function(val) {
return Object.prototype.toString.call(val)
.match(/^\[object\s(.*)\]$/)[1];
};
//Defines the type of the value, extended typeof
var whatis = function(val) {
if (val === undefined)
return 'undefined';
if (val === null)
return 'null';
var type = typeof val;
if (type === 'object')
type = getClass(val).toLowerCase();
if (type === 'number') {
if (val.toString().indexOf('.') > 0)
return 'float';
else
return 'integer';
}
return type;
};
var compareObjects = function(a, b) {
if (a === b)
return true;
for (var i in a) {
if (b.hasOwnProperty(i)) {
if (!equal(a[i],b[i])) return false;
} else {
return false;
}
}
for (var i in b) {
if (!a.hasOwnProperty(i)) {
return false;
}
}
return true;
};
var compareArrays = function(a, b) {
if (a === b)
return true;
if (a.length !== b.length)
return false;
for (var i = 0; i < a.length; i++){
if(!equal(a[i], b[i])) return false;
};
return true;
};
var _equal = {};
_equal.array = compareArrays;
_equal.object = compareObjects;
_equal.date = function(a, b) {
return a.getTime() === b.getTime();
};
_equal.regexp = function(a, b) {
return a.toString() === b.toString();
};
// uncoment to support function as string compare
// _equal.fucntion = _equal.regexp;
/*
* Are two values equal, deep compare for objects and arrays.
* @param a {any}
* @param b {any}
* @return {boolean} Are equal?
*/
var equal = function(a, b) {
if (a !== b) {
var atype = whatis(a), btype = whatis(b);
if (atype === btype)
return _equal.hasOwnProperty(atype) ? _equal[atype](a, b) : a==b;
return false;
}
return true;
};
//----- USAGE -----//
//Someone on stack overflow had nice tests, thanks! :)
function assertFalse(bool) {
console.error(!bool);
}
function assertTrue(bool) {
console.error(bool);
}
assertFalse(equal({}, null));
assertFalse(equal({}, undefined));
assertTrue(equal('hi','hi'));
assertTrue(equal(5,5));
assertFalse(equal(5,10));
assertFalse(equal(1,'1'));
assertTrue(equal([],[]));
assertTrue(equal([1,2],[1,2]));
assertFalse(equal([1,2],[2,1]));
assertFalse(equal([1,2],[1,2,3]));
assertTrue(equal(new Date("2011-03-31"), new Date("2011-03-31")));
assertFalse(equal(new Date("2011-03-31"), new Date("1970-01-01")));
assertTrue(equal({},{}));
assertTrue(equal({a:1,b:2},{a:1,b:2}));
assertTrue(equal({a:1,b:2},{b:2,a:1}));
assertFalse(equal({a:1,b:2},{a:1,b:3}));
assertTrue(equal({1:{name:"mhc",age:28}, 2:{name:"arb",age:26}},{1:{name:"mhc",age:28}, 2:{name:"arb",age:26}}));
assertFalse(equal({1:{name:"mhc",age:28}, 2:{name:"arb",age:26}},{1:{name:"mhc",age:28}, 2:{name:"arb",age:27}}));
assertFalse(equal(function(x){return x;},function(x){return x;}));
assertFalse(equal(function(x){return x;},function(y){return y+2;}));
var a = {a: 'text', b:[0,1]};
var b = {a: 'text', b:[0,1]};
var c = {a: 'text', b: 0};
var d = {a: 'text', b: false};
var e = {a: 'text', b:[1,0]};
var f = {a: 'text', b:[1,0], f: function(){ this.f = this.b; }};
var g = {a: 'text', b:[1,0], f: function(){ this.f = this.b; }};
var h = {a: 'text', b:[1,0], f: function(){ this.a = this.b; }};
var i = {
a: 'text',
c: {
b: [1, 0],
f: function(){
this.a = this.b;
}
}
};
var j = {
a: 'text',
c: {
b: [1, 0],
f: function(){
this.a = this.b;
}
}
};
var k = {a: 'text', b: null};
var l = {a: 'text', b: undefined};
assertTrue(equal(a,b));
assertFalse(equal(a,c));
assertFalse(equal(c,d));
assertFalse(equal(a,e));
assertFalse(equal(f,g));
assertFalse(equal(h,g));
assertFalse(equal(i,j));
assertFalse(equal(d,k));
assertFalse(equal(k,l));
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