Leap year and general date validation for isDate().

test/validators.js

@@ -860,6 +860,13 @@ describe('Validators', function () {
               , '2011.08.04'
               , '4. 8. 2011. GMT'
               , '2011-08-04 12:00'
+              , '2/29/24'
+              , '2-29-24'
+              , '12'
+              , '11/2/23 12:24'
+              , new Date()
+              , 'Mon Aug 17 2015 00:24:56 GMT-0500 (CDT)'
+              , '2/22/23 23:24:26'
             ]
           , invalid: [
                 'foo'

validator.js

@@ -468,7 +468,37 @@
     };
 
     validator.isDate = function (str) {
-        return !isNaN(Date.parse(str));
+        var normalizedDate = new Date((new Date(str)).toUTCString());
+        var regularDay = String(normalizedDate.getDate());
+        var utcDay = String(normalizedDate.getUTCDate());
+        var dayOrYear, dayOrYearMatches, year;
+        if (isNaN(Date.parse(normalizedDate))) {
+            return false;
+        }
+        if (typeof str !== 'string') {
+          return true;  //if Date.parse() passes, it's the current time
+        }
+        //check for valid double digits that could be late days
+        //check for all matches since a string like '12/23' is a valid date
+        //ignore everything with nearby colons
+        dayOrYearMatches = str.match(/(^|[^:])[23]\d([^:\d]|$)/g);
+        if (!dayOrYearMatches) {
+            return true;
+        }
+        dayOrYear = dayOrYearMatches.map(function(digitString) {
+            return digitString.match(/\d+/g)[0];
+        }).join('/');
+        year = String(normalizedDate.getFullYear()).slice(-2);
+        //local date and UTC date can differ, but both are valid, so check agains both
+        if (dayOrYear === regularDay || dayOrYear === utcDay || dayOrYear === year) {
+            return true;
+        } else if ((dayOrYear === (regularDay + '/' + year)) || (dayOrYear === (year + '/' + regularDay))) {
+            return true;
+        } else if ((dayOrYear === (utcDay + '/' + year)) || (dayOrYear === (year + '/' + utcDay))) {
+            return true;
+        } else {
+            return false;
+        }
     };
 
     validator.isAfter = function (str, date) {