Go back to silently returning the event if the bus is not started (#26)

src/main/java/net/neoforged/bus/EventBus.java

@@ -343,6 +343,9 @@ public void unregister(Object object)
 
     @Override
     public <T extends Event> T post(T event) {
+        if (shutdown) {
+            return event;
+        }
         doPostChecks(event);
 
         return post(event, getListenerList(event.getClass()).getListeners());
@@ -354,17 +357,15 @@ public <T extends Event> T post(EventPriority phase, T event) {
             throw new IllegalStateException("This bus does not allow calling phase-specific post.");
         }
 
+        if (shutdown) {
+            return event;
+        }
         doPostChecks(event);
 
         return post(event, getListenerList(event.getClass()).getPhaseListeners(phase));
     }
 
     private void doPostChecks(Event event) {
-        if (shutdown)
-        {
-            throw new IllegalStateException("Attempted to post event of type " +
-                    event.getClass().getSimpleName() + " on a bus that was not started yet!");
-        }
         if (checkTypesOnDispatch)
         {
             try {

src/main/java/net/neoforged/bus/api/IEventBus.java

@@ -194,24 +194,26 @@ public interface IEventBus {
 
     /**
      * Submit the event for dispatch to appropriate listeners
+     * <p>
+     * If this bus was not started yet, the event is returned without being dispatched.
      *
      * @param event The event to dispatch to listeners
      * @return the event that was passed in
-     * @throws IllegalStateException if the bus is not started yet
      */
     <T extends Event> T post(T event);
 
     /**
      * Submit the event for dispatch to listeners registered with a specific {@link EventPriority}.
      * <p>
+     * If this bus was not started yet, the event is returned without being dispatched.
+     * <p>
      * Manually posting events phase-by-phase through this method is less performant
      * than dispatching to all phases through a {@link #post(Event)} call.
      * Prefer that method when per-phase dispatching is not needed.
      *
      * @param event The event to dispatch to listeners
      * @return the event that was passed in
      * @throws IllegalStateException if the bus does not allow per-phase post
-     * @throws IllegalStateException if the bus is not started yet
      * @see BusBuilder#allowPerPhasePost()
      */
     <T extends Event> T post(EventPriority phase, T event);