Add support for NaN

Author: vagos

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|L)-' + UID + '-(\\d+)__@"', 'g');
+var PLACE_HOLDER_REGEXP = new RegExp('(\\\\)?"@__(F|R|D|M|S|A|U|I|B|L|N)-' + UID + '-(\\d+)__@"', 'g');
 
 var IS_NATIVE_CODE_REGEXP = /\{\s*\[native code\]\s*\}/g;
 var IS_PURE_FUNCTION = /function.*?\(/;
@@ -73,6 +73,7 @@ module.exports = function serialize(obj, options) {
     var infinities= [];
     var bigInts = [];
     var urls = [];
+    var nans = [];
 
     // Returns placeholders for functions and regexps (identified by index)
     // which are later replaced by their string representation.
@@ -83,6 +84,10 @@ module.exports = function serialize(obj, options) {
             deleteFunctions(value);
         }
 
+        if (typeof value === 'number' && isNaN(value)) {
+            return '@__N-' + UID + '-' + (nans.push(value) - 1) + '__@';
+        }
+
         if (!value && value !== undefined && value !== BigInt(0)) {
             return value;
         }
@@ -210,7 +215,7 @@ 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 && urls.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 && nans.length === 0) {
         return str;
     }
 
@@ -261,6 +266,10 @@ module.exports = function serialize(obj, options) {
             return "new URL(" + serialize(urls[valueIndex].toString(), options) + ")";
         }
 
+        if (type === 'N') {
+            return 'NaN';
+        }
+
         var fn = functions[valueIndex];
 
         return serializeFunc(fn);

test/unit/serialize.js

@@ -554,6 +554,19 @@ describe('serialize( obj )', function () {
         });
     });
 
+    describe('NaN', function () {
+        it('should serialize NaN', function () {
+            expect(serialize(NaN)).to.equal('NaN');
+            expect(serialize({t: [NaN]})).to.be.a('string').equal('{"t":[NaN]}');
+        });
+
+        it('should deserialize NaN', function () {
+            var d = eval(serialize(NaN));
+            expect(d).to.be.a('Number');
+            expect(isNaN(d)).to.equal(true);
+        });
+    });
+
     describe('backwards-compatability', function () {
         it('should accept `space` as the second argument', function () {
             expect(serialize([1], 0)).to.equal('[1]');