From e768ca164336180dcb0b321888f5bb60bdc16b88 Mon Sep 17 00:00:00 2001
From: Gregory Terzian <gterzian@users.noreply.github.com>
Date: Thu, 9 Jan 2020 16:12:08 +0800
Subject: add a generic utility to convert a slice into a frozen array

---
 components/script/dom/messageevent.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'components/script/dom/messageevent.rs')

diff --git a/components/script/dom/messageevent.rs b/components/script/dom/messageevent.rs
index 0bb2ea1fd7a..d7f32cb7c1a 100644
--- a/components/script/dom/messageevent.rs
+++ b/components/script/dom/messageevent.rs
@@ -13,7 +13,7 @@ use crate::dom::bindings::reflector::reflect_dom_object;
 use crate::dom::bindings::root::{Dom, DomRoot};
 use crate::dom::bindings::str::DOMString;
 use crate::dom::bindings::trace::RootedTraceableBox;
-use crate::dom::bindings::utils::message_ports_to_frozen_array;
+use crate::dom::bindings::utils::to_frozen_array;
 use crate::dom::event::Event;
 use crate::dom::eventtarget::EventTarget;
 use crate::dom::globalscope::GlobalScope;
@@ -244,7 +244,7 @@ impl MessageEventMethods for MessageEvent {
             .iter()
             .map(|port| DomRoot::from_ref(&**port))
             .collect();
-        message_ports_to_frozen_array(ports.as_slice(), cx)
+        to_frozen_array(ports.as_slice(), cx)
     }
 
     /// <https://html.spec.whatwg.org/multipage/#dom-messageevent-initmessageevent>
-- 
cgit v1.2.3


From 03396011282d527c0fc5e530925877902199e053 Mon Sep 17 00:00:00 2001
From: Gregory Terzian <gterzian@users.noreply.github.com>
Date: Sat, 11 Jan 2020 22:35:50 +0800
Subject: cache frozen array of ports

---
 components/script/dom/messageevent.rs | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

(limited to 'components/script/dom/messageevent.rs')

diff --git a/components/script/dom/messageevent.rs b/components/script/dom/messageevent.rs
index d7f32cb7c1a..54a6f2ee588 100644
--- a/components/script/dom/messageevent.rs
+++ b/components/script/dom/messageevent.rs
@@ -61,6 +61,8 @@ pub struct MessageEvent {
     source: DomRefCell<Option<SrcObject>>,
     lastEventId: DomRefCell<DOMString>,
     ports: DomRefCell<Vec<Dom<MessagePort>>>,
+    #[ignore_malloc_size_of = "mozjs"]
+    frozen_ports: DomRefCell<Option<Heap<JSVal>>>,
 }
 
 impl MessageEvent {
@@ -82,6 +84,7 @@ impl MessageEvent {
                     .map(|port| Dom::from_ref(&*port))
                     .collect(),
             ),
+            frozen_ports: DomRefCell::new(None),
         }
     }
 
@@ -238,13 +241,24 @@ impl MessageEventMethods for MessageEvent {
 
     /// <https://html.spec.whatwg.org/multipage/#dom-messageevent-ports>
     fn Ports(&self, cx: JSContext) -> JSVal {
+        if let Some(ports) = &*self.frozen_ports.borrow() {
+            return ports.get();
+        }
+
         let ports: Vec<DomRoot<MessagePort>> = self
             .ports
             .borrow()
             .iter()
             .map(|port| DomRoot::from_ref(&**port))
             .collect();
-        to_frozen_array(ports.as_slice(), cx)
+        let frozen_ports = to_frozen_array(ports.as_slice(), cx);
+
+        // Cache the Js value.
+        let heap_val = Heap::default();
+        heap_val.set(frozen_ports);
+        *self.frozen_ports.borrow_mut() = Some(heap_val);
+
+        frozen_ports
     }
 
     /// <https://html.spec.whatwg.org/multipage/#dom-messageevent-initmessageevent>
@@ -268,6 +282,7 @@ impl MessageEventMethods for MessageEvent {
             .into_iter()
             .map(|port| Dom::from_ref(&*port))
             .collect();
+        *self.frozen_ports.borrow_mut() = None;
         self.event
             .init_event(Atom::from(type_), bubbles, cancelable);
     }
-- 
cgit v1.2.3