src/jdk/nashorn/internal/runtime/PropertyDescriptor.java

rev 754 : 8030197: Nashorn: Object.defineProperty() can be lured to change fixed NaN property
Reviewed-by: attila, jlaskey

@@ -149,7 +149,14 @@
      *
      * @param key property key
      * @return true if property exists in implementor
      */
     public boolean has(Object key);
+
+    /**
+     * Check existence and compare attributes of descriptors.
+     *
+     * @return true if every field of this desc exists in otherDesc and has the same value.
+     */
+    public boolean hasAndEquals(PropertyDescriptor otherDesc);
 }