Add /paper dumplisteners command

paper-api/src/main/java/org/bukkit/plugin/EventExecutor.java

@@ -70,9 +70,18 @@ public interface EventExecutor {
             try {
                 EventExecutor asmExecutor = executorClass.newInstance();
                 // Define a wrapper to conform to bukkit stupidity (passing in events that don't match and wrapper exception)
-                return (listener, event) -> {
-                    if (!eventClass.isInstance(event)) return;
-                    asmExecutor.execute(listener, event);
+                return new EventExecutor() {
+                    @Override
+                    public void execute(@NotNull Listener listener, @NotNull Event event) throws EventException {
+                        if (!eventClass.isInstance(event)) return;
+                        asmExecutor.execute(listener, event);
+                    }
+
+                    @Override
+                    @NotNull
+                    public String toString() {
+                        return "ASMEventExecutor['" + m + "']";
+                    }
                 };
             } catch (InstantiationException | IllegalAccessException e) {
                 throw new AssertionError("Unable to initialize generated event executor", e);

paper-api/src/main/java/org/bukkit/plugin/RegisteredListener.java

@@ -78,4 +78,27 @@ public class RegisteredListener {
     public boolean isIgnoringCancelled() {
         return ignoreCancelled;
     }
+
+    // Paper start
+    /**
+     * Get the executor for this registration.
+     *
+     * @return executor
+     */
+    @NotNull
+    public EventExecutor getExecutor() {
+        return this.executor;
+    }
+
+    @Override
+    public String toString() {
+        return "RegisteredListener{"
+            + "plugin=\"" + this.plugin.getName()
+            + "\", listener=\"" + this.listener
+            + "\", executor=\"" + this.executor
+            + "\", priority=\"" + this.priority.name() + " (" + this.priority.getSlot() + ")"
+            + "\", ignoringCancelled=" + this.ignoreCancelled
+            + "}";
+    }
+    // Paper end
 }