diff --git a/demo/nodejs/index.js b/demo/nodejs/index.js
index 13e1acfcc..321eefb07 100644
--- a/demo/nodejs/index.js
+++ b/demo/nodejs/index.js
@@ -1,5 +1,4 @@
-// const Liquid = require('../..')
-const Liquid = require('../../dist/liquid.common.js')
+const Liquid = require('../..')
 
 const engine = new Liquid({
   root: __dirname,
diff --git a/src/util/underscore.js b/src/util/underscore.js
index 3857e3219..e6b1fe8b5 100644
--- a/src/util/underscore.js
+++ b/src/util/underscore.js
@@ -19,8 +19,8 @@ export function stringify (value) {
   if (typeof value.toLiquid === 'function') {
     return stringify(value.toLiquid())
   }
-  if (isString(value)) {
-    return value
+  if (isString(value) || value instanceof RegExp || value instanceof Date) {
+    return value.toString()
   }
 
   const cache = []
diff --git a/test/unit/util/underscore.js b/test/unit/util/underscore.js
index 32657d435..2a006234d 100644
--- a/test/unit/util/underscore.js
+++ b/test/unit/util/underscore.js
@@ -51,6 +51,11 @@ describe('util/underscore', function () {
     it('should return "undefined" for undefined', function () {
       expect(_.stringify(undefined)).to.equal('undefined')
     })
+    it('should return locale string for date', function () {
+      const date = new Date('2018-10-01T14:51:00.000Z')
+      // Mon Oct 01 2018 22:51:00 GMT+0800 (CST)
+      expect(_.stringify(date)).to.equal(date.toString())
+    })
   })
   describe('.forOwn()', function () {
     it('should iterate all properties', function () {