Add support for URL's (yahoo#123)

Author: rrdelaney

index.js

@@ -11,7 +11,7 @@ var randomBytes = require('randombytes');
 // Generate an internal UID to make the regexp pattern harder to guess.
 var UID_LENGTH          = 16;
 var UID                 = generateUID();
-var PLACE_HOLDER_REGEXP = new RegExp('(\\\\)?"@__(F|R|D|M|S|A|U|I|B)-' + UID + '-(\\d+)__@"', 'g');
+var PLACE_HOLDER_REGEXP = new RegExp('(\\\\)?"@__(F|R|D|M|S|A|U|I|B|L)-' + UID + '-(\\d+)__@"', 'g');
 
 var IS_NATIVE_CODE_REGEXP = /\{\s*\[native code\]\s*\}/g;
 var IS_PURE_FUNCTION = /function.*?\(/;
@@ -72,6 +72,7 @@ module.exports = function serialize(obj, options) {
     var undefs    = [];
     var infinities= [];
     var bigInts = [];
+    var urls = [];
 
     // Returns placeholders for functions and regexps (identified by index)
     // which are later replaced by their string representation.
@@ -114,6 +115,10 @@ module.exports = function serialize(obj, options) {
                     return '@__A-' + UID + '-' + (arrays.push(origValue) - 1) + '__@';
                 }
             }
+
+            if(origValue instanceof URL) {
+                return '@__L-' + UID + '-' + (urls.push(origValue) - 1) + '__@';
+            }
         }
 
         if (type === 'function') {
@@ -205,7 +210,7 @@ module.exports = function serialize(obj, options) {
         str = str.replace(UNSAFE_CHARS_REGEXP, escapeUnsafeChars);
     }
 
-    if (functions.length === 0 && regexps.length === 0 && dates.length === 0 && maps.length === 0 && sets.length === 0 && arrays.length === 0 && undefs.length === 0 && infinities.length === 0 && bigInts.length === 0) {
+    if (functions.length === 0 && regexps.length === 0 && dates.length === 0 && maps.length === 0 && sets.length === 0 && arrays.length === 0 && undefs.length === 0 && infinities.length === 0 && bigInts.length === 0 && urls.length === 0) {
         return str;
     }
 
@@ -252,6 +257,10 @@ module.exports = function serialize(obj, options) {
             return "BigInt(\"" + bigInts[valueIndex] + "\")";
         }
 
+        if (type === 'L') {
+            return "new URL(\"" + urls[valueIndex].toString() + "\")"; 
+        }
+
         var fn = functions[valueIndex];
 
         return serializeFunc(fn);

test/unit/serialize.js

@@ -452,6 +452,20 @@ describe('serialize( obj )', function () {
         });
     });
 
+    describe('URL', function () {
+        it('should serialize URL', function () {
+            var u = new URL('https://x.com/')
+            expect(serialize(u)).to.equal('new URL("https://x.com/")');
+            expect(serialize({t: [u]})).to.be.a('string').equal('{"t":[new URL("https://x.com/")]}');
+        });
+
+        it('should deserialize URL', function () {
+            var d = eval(serialize(new URL('https://x.com/')));
+            expect(d).to.be.a('URL');
+            expect(d.toString()).to.equal('https://x.com/');
+        });
+    });
+
     describe('XSS', function () {
         it('should encode unsafe HTML chars to Unicode', function () {
             expect(serialize('</script>')).to.equal('"\\u003C\\u002Fscript\\u003E"');