Delay listening behavior logic until after the event implementation i…

…nitializes (#6948)

src/main/java/ch/njol/skript/events/EvtMove.java

@@ -132,15 +132,14 @@ public boolean check(Event event) {
 	}
 
 	@Override
-	@Nullable
 	@SuppressWarnings("unchecked")
 	public Class<? extends Event> [] getEventClasses() {
 		if (isPlayer) {
 			return new Class[] {PlayerMoveEvent.class};
 		} else if (HAS_ENTITY_MOVE) {
 			return new Class[] {EntityMoveEvent.class};
 		}
-		return null;
+		throw new IllegalStateException("This event has not yet initialized!");
 	}
 
 	@Override

src/main/java/ch/njol/skript/lang/SkriptEvent.java

@@ -85,27 +85,32 @@ public final boolean init(Literal<?>[] args, int matchedPattern, ParseResult par
 			throw new IllegalStateException();
 		skriptEventInfo = (SkriptEventInfo<?>) syntaxElementInfo;
 
+		assert entryContainer != null; // cannot be null for non-simple structures
+		this.source = entryContainer.getSource();
+
+		// use default value for now
+		listeningBehavior = eventData.getListenerBehavior();
+
+		// initialize implementation
+		if (!init(args, matchedPattern, parseResult))
+			return false;
+
 		// evaluate whether this event supports listening to cancelled events
-		supportsListeningBehavior = false;
 		for (Class<? extends Event> eventClass : getEventClasses()) {
 			if (Cancellable.class.isAssignableFrom(eventClass)) {
 				supportsListeningBehavior = true;
 				break;
 			}
 		}
 
-		listeningBehavior = eventData.getListenerBehavior();
 		// if the behavior is non-null, it was set by the user
 		if (listeningBehavior != null && !isListeningBehaviorSupported()) {
 			String eventName = skriptEventInfo.name.toLowerCase(Locale.ENGLISH);
 			Skript.error(Utils.A(eventName) + " event does not support listening for cancelled or uncancelled events.");
 			return false;
 		}
 
-		assert entryContainer != null; // cannot be null for non-simple structures
-		this.source = entryContainer.getSource();
-
-		return init(args, matchedPattern, parseResult);
+		return true;
 	}
 
 	/**