deep clone object/array mixed

deep-clone.js

function isArray(obj) {
    var str = Object.prototype.toString.call(obj).slice(8, -1);
    return (str === 'Array');
}

function deepClone(obj) {
    var copy = isArray(obj) ? [] : {};
    
    for(var p in obj) {
        if(!obj.hasOwnProperty(p)) continue;
        
        if(isArray(obj[p])) {
            copy[p] = deepClone(obj[p], []);
        } else if(typeof obj[p] === 'object') {
            copy[p] = deepClone(obj[p]);
        } else {
            copy[p] = obj[p];
        }
    }
    
    return copy;
}

var a = {
    key1: 1,
    key2: 'a',
    key3: false,
    key4: null,
    key5: undefined,
    key6: [1, 2, 3, 4, 5],
    key7: {
        key7_1: [{
            hoge: 1,
            foo: 2,
            bar: 3,
        }]
    }
}
var b = deepClone(a);

console.assert(b !== a, 'b !== a');

b.key1 = 2;
console.assert(b.key1 !== a.key1, 'b.key1 !== a.key1');

b.key2 = 'b';
console.assert(b.key2 !== a.key2, 'b.key2 !== a.key2');

b.key3 = true;
console.assert(b.key3 !== a.key3, 'b.key3 !== a.key3');

b.key4 = undefined;
console.assert(b.key4 !== a.key4, 'b.key4 !== a.key4');

b.key5 = null;
console.assert(b.key5 !== a.key5, 'b.key5 !== a.key5');

console.assert(b.key6 !== a.key6, 'b.key6 !== a.key6');
b.key6[0] += 100;
console.assert(b.key6[0] !== a.key6[0], 'b.key6[0] !== a.key6[0]');

console.assert(b.key7 !== a.key7, 'b.key7 !== a.key7');
console.assert(b.key7.key7_1 !== a.key7.key7_1, 'b.key7.key7_1 !== a.key7.key7_1');
console.assert(b.key7.key7_1[0] !== a.key7.key7_1[0], 'b.key7.key7_1[0] !== a.key7.key7_1[0]');

b.key7.key7_1[0].hoge = 'aaa';
console.assert(b.key7.key7_1[0].hoge !== a.key7.key7_1[0].hoge, 'b.key7.key7_1[0].hoge !== a.key7.key7_1[0].hoge');