huskies: merge 858

server/src/pipeline_state/events.rs

@@ -21,21 +21,25 @@ pub trait TransitionSubscriber: Send + Sync {
     fn on_transition(&self, fired: &TransitionFired);
 }
 
+/// Collects [`TransitionSubscriber`]s and dispatches [`TransitionFired`] events to each.
 pub struct EventBus {
     subscribers: Vec<Box<dyn TransitionSubscriber>>,
 }
 
 impl EventBus {
+    /// Create an empty event bus with no subscribers.
     pub fn new() -> Self {
         Self {
             subscribers: Vec::new(),
         }
     }
 
+    /// Register a subscriber to receive all future transition events.
     pub fn subscribe<S: TransitionSubscriber + 'static>(&mut self, subscriber: S) {
         self.subscribers.push(Box::new(subscriber));
     }
 
+    /// Fire a transition event, calling every registered subscriber in order.
     pub fn fire(&self, event: TransitionFired) {
         for sub in &self.subscribers {
             sub.on_transition(&event);