fix: Listeners::once can be called multiple times (#15475)

* fix: `Listeners::once` can be called multiple times

* typo

Author: Legend-Master

.changes/listener-event-once-multiple-times.md

@@ -0,0 +1,5 @@
+---
+"tauri": "patch:bug"
+---
+
+Fix `Listener::once` can be called multiple times if they trigger `emit`(s) inside the handler

crates/tauri/src/event/listener.rs

@@ -168,11 +168,11 @@ impl Listeners {
 
     self.listen(event, target, move |event| {
       let id = event.id;
+      self_.unlisten(id);
       let handler = handler
         .take()
         .expect("attempted to call handler more than once");
       handler(event);
-      self_.unlisten(id);
     })
   }
 
@@ -382,4 +382,20 @@ mod test {
       assert!(l.contains_key(&key));
     }
   }
+
+  #[test]
+  fn event_no_deadlocks() {
+    let listeners = Listeners::default();
+    let listeners_clone = listeners.clone();
+    let event = crate::EventName::new("test-event".to_owned()).unwrap();
+    let event_clone = event.clone();
+    listeners.once(event.clone(), EventTarget::Any, move |_event| {
+      listeners_clone
+        .emit(EmitArgs::new(event_clone.as_str_event(), &()).unwrap())
+        .unwrap();
+    });
+    listeners
+      .emit(EmitArgs::new(event.as_str_event(), &()).unwrap())
+      .unwrap();
+  }
 }