avm2: Get event.target to determine if clone() is necessary

core/src/avm2/events.rs

@@ -75,6 +75,7 @@ pub struct Event<'gc> {
     event_type: AvmString<'gc>,
 
     /// Whether is event has been dispatched before.
+    // TODO: this field may be redundant now?
     dispatched: bool,
 }
 
@@ -459,9 +460,11 @@ pub fn dispatch_event<'gc>(
         parent = parent_dobj.parent();
     }
 
-    let dispatched = event.as_event().unwrap().dispatched;
+    let has_target = event
+        .get_public_property("target", activation)?
+        .coerce_to_boolean();
 
-    let event = if dispatched {
+    let event = if has_target {
         event
             .call_public_property("clone", &[], activation)?
             .as_object()

tests/tests/swfs/avm2/event_target_getter/Test.as

@@ -0,0 +1,63 @@
+// compiled with mxmlc
+
+import flash.events.Event;
+import flash.display.DisplayObject;
+
+package {
+    import flash.display.MovieClip;
+    import flash.display.DisplayObject;
+    import flash.events.Event;
+
+    public class Test extends MovieClip {
+        public function Test(){
+            var d = new MovieClip();
+            trace("// testing trivial getter")
+            var e1 = new E1("e1", d);
+            d.dispatchEvent(e1);
+
+            trace("// testing 1-cycle-delayed getter")
+            var e2 = new E2("e2", d);
+            d.dispatchEvent(e2);
+        }
+
+    }
+}
+
+
+class E1 extends Event {
+    private var dobj: DisplayObject;
+    public function E1(type, dobj){
+        super(type, false, false);
+        this.dobj = dobj;
+    }
+    override public function get target(): Object {
+        trace("in get target()");
+        return this.dobj;
+    }
+    override public function clone(): Event {
+        trace("in clone()");
+        return new E1(this.type, this.dobj);
+    }
+}
+
+class E2 extends Event {
+    private var ready: Boolean;
+    private var dobj: DisplayObject;
+    public function E2(type, d){
+        super(type, false, false);
+        this.ready = false;
+        this.dobj = dobj;
+    }
+    override public function get target(): Object {
+        trace("in get target()");
+        if (this.ready) {
+            return this.dobj;
+        }
+        this.ready = true;
+        return null;
+    }
+    override public function clone(): Event {
+        trace("in clone()");
+        return new E2(this.type, this.dobj);
+    }
+}

tests/tests/swfs/avm2/event_target_getter/output.txt

@@ -0,0 +1,5 @@
+// testing trivial getter
+in get target()
+in clone()
+// testing 1-cycle-delayed getter
+in get target()

tests/tests/swfs/avm2/event_target_getter/test.toml

@@ -0,0 +1,2 @@
+# The test observes event dispatching getting `.target` to check if even is being re-dispatched.
+num_frames = 1