src/java.base/share/classes/jdk/internal/module/ModulePatcher.java

@@ -173,10 +173,16 @@
      */
     public boolean isEmpty() {
         return map.isEmpty();
     }
 
+    /*
+     * Returns the names of the patched modules.
+     */
+    Set<String> patchedModules() {
+        return map.keySet();
+    }
 
     /**
      * A ModuleReader that reads resources from a patched module.
      *
      * This class is public so as to expose the findResource method to the