@@ -598,11 +598,16 @@ public static void validateAttrDeclaration(
      * @param value value.
      * @return {boolean}
      */
-    public static boolean attrValueHasTemplateSyntax(@Nonnull final String value) {
+    public static boolean attrValueHasTemplateSyntax(final String value) {
         // Mustache (https://mustache.github.io/mustache.5.html), our template
         // system, supports replacement tags that start with {{ and end with }}.
         // We relax attribute value rules if the value contains this syntax as we
         // will validate the post-processed tag instead.
+
+        if (value == null) {
+            return false;
+        }
+
         return MUSTACHE_TAG_PATTERN.matcher(value).matches();
     }
 
 
@@ -55,6 +55,21 @@ public void testAmpSelectorsPass() {
     }
   }
 
+  @Test
+  public void testCarousel() {
+    try {
+      String inputHtml =
+              readFile(
+                      "test-cases/tags/testAmpCarousel.html");
+      final int maxNode = 10000;
+      ValidatorProtos.ValidationResult result =
+              ampHtmlParser.parse(inputHtml, ValidatorProtos.HtmlFormat.Code.AMP4EMAIL, ExitCondition.FULL_PARSING, maxNode);
+      Assert.assertEquals(result.getErrorsCount(), 0, "Expecting to have 0 error");
+    } catch (final IOException ex) {
+      ex.printStackTrace();
+    }
+  }
+
   @Test
   public void testAmpList() {
     try {
 
@@ -1,9 +1,6 @@
 <!--
      AMP-LIST
 -->
-<!--
-     AMP-LIST
--->
 <!doctype html>
 <html ⚡4email>
 <head>