diff --git a/lib/js/Gruntfile.js b/lib/js/Gruntfile.js
index 4aa450f..1dcead6 100644
--- a/lib/js/Gruntfile.js
+++ b/lib/js/Gruntfile.js
@@ -55,6 +55,9 @@
       ThriftGenDeepConstructor: {
         command: '../../compiler/cpp/thrift -gen js -o test ../../test/JsDeepConstructorTest.thrift'
       },
+      ThriftGenDoubleConstants: {
+        command: '../../compiler/cpp/thrift -gen js -o test ../../test/DoubleConstantsTest.thrift'
+      },
       ThriftGenES6: {
         command: '../../compiler/cpp/thrift -gen js -gen js:es6 -o test ../../test/ThriftTest.thrift'
       },
@@ -94,6 +97,14 @@
           ]
         }
       },
+      ThriftJS_DoubleRendering: {
+        options: {
+          '--ignore-ssl-errors': true,
+          urls: [
+            'http://localhost:8088/test-double-rendering.html'
+          ]
+        }
+      },
       ThriftWS: {
         options: {
           urls: [