Halt keystroke dispatch immediately when we call a global action handler

Nathan Sobo created 4 years ago

Someday, we may want to define a global action context that allows us to propagate the action, but this isn't currently supported. Previous to this commit, we were invoking the same global action handler multiple times, once for each view in the responder chain.

Change summary

crates/gpui/src/app.rs | 28 ++++++++++++++++------------
1 file changed, 16 insertions(+), 12 deletions(-)

Detailed changes

crates/gpui/src/app.rs

@@ -667,7 +667,7 @@ pub struct MutableAppContext {
     assets: Arc<AssetCache>,
     cx: AppContext,
     actions: HashMap<TypeId, HashMap<TypeId, Vec<Box<ActionCallback>>>>,
-    global_actions: HashMap<TypeId, Vec<Box<GlobalActionCallback>>>,
+    global_actions: HashMap<TypeId, Box<GlobalActionCallback>>,
     keystroke_matcher: keymap::Matcher,
     next_entity_id: usize,
     next_window_id: usize,
@@ -838,10 +838,13 @@ impl MutableAppContext {
             handler(action, cx);
         });
 
-        self.global_actions
-            .entry(TypeId::of::<A>())
-            .or_default()
-            .push(handler);
+        if self
+            .global_actions
+            .insert(TypeId::of::<A>(), handler)
+            .is_some()
+        {
+            panic!("registered multiple global handlers for the same action type");
+        }
     }
 
     pub fn window_ids(&self) -> impl Iterator<Item = usize> + '_ {
@@ -1125,7 +1128,7 @@ impl MutableAppContext {
             }
 
             if !halted_dispatch {
-                this.dispatch_global_action_any(action);
+                halted_dispatch = this.dispatch_global_action_any(action);
             }
             halted_dispatch
         })
@@ -1135,13 +1138,14 @@ impl MutableAppContext {
         self.dispatch_global_action_any(&action);
     }
 
-    fn dispatch_global_action_any(&mut self, action: &dyn AnyAction) {
+    fn dispatch_global_action_any(&mut self, action: &dyn AnyAction) -> bool {
         self.update(|this| {
-            if let Some((name, mut handlers)) = this.global_actions.remove_entry(&action.id()) {
-                for handler in handlers.iter_mut().rev() {
-                    handler(action, this);
-                }
-                this.global_actions.insert(name, handlers);
+            if let Some((name, mut handler)) = this.global_actions.remove_entry(&action.id()) {
+                handler(action, this);
+                this.global_actions.insert(name, handler);
+                true
+            } else {
+                false
             }
         })
     }