Auto merge of #24636 - saschanaz:windowproxy, r=nox,jdm

Use MessageEventSource on MessageEvent IDL

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---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #22617

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because ___

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4 files changed, 84 insertions, 32 deletions

diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index 77c3c776c3e..e660471364e 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -836,6 +836,8 @@ def getJSToNativeConversionInfo(type, descriptorProvider, failureCode=None,
             descriptorType = descriptor.nativeType
         elif isArgument:
             descriptorType = descriptor.argumentType
+        elif descriptor.interface.identifier.name == "WindowProxy":
+            conversionFunction = "windowproxy_from_handlevalue"
 
         if failureCode is None:
             substitutions = {
@@ -2409,6 +2411,7 @@ def UnionTypes(descriptors, dictionaries, callbacks, typedefs, config):
         'crate::dom::bindings::conversions::ConversionBehavior',
         'crate::dom::bindings::conversions::StringificationBehavior',
         'crate::dom::bindings::conversions::root_from_handlevalue',
+        'crate::dom::bindings::conversions::windowproxy_from_handlevalue',
         'std::ptr::NonNull',
         'crate::dom::bindings::record::Record',
         'crate::dom::bindings::num::Finite',
@@ -2419,6 +2422,7 @@ def UnionTypes(descriptors, dictionaries, callbacks, typedefs, config):
         'crate::dom::bindings::trace::RootedTraceableBox',
         'crate::dom::bindings::utils::find_enum_value',
         'crate::dom::types::*',
+        'crate::dom::windowproxy::WindowProxy',
         'crate::script_runtime::JSContext as SafeJSContext',
         'js::error::throw_type_error',
         'js::rust::HandleValue',
diff --git a/components/script/dom/bindings/conversions.rs b/components/script/dom/bindings/conversions.rs
index c84adf64dbb..863c84c0512 100644
--- a/components/script/dom/bindings/conversions.rs
+++ b/components/script/dom/bindings/conversions.rs
@@ -45,6 +45,7 @@ use crate::dom::htmlcollection::HTMLCollection;
 use crate::dom::htmlformcontrolscollection::HTMLFormControlsCollection;
 use crate::dom::htmloptionscollection::HTMLOptionsCollection;
 use crate::dom::nodelist::NodeList;
+use crate::dom::windowproxy::WindowProxy;
 use js::conversions::latin1_to_string;
 pub use js::conversions::ConversionBehavior;
 pub use js::conversions::{ConversionResult, FromJSValConvertible, ToJSValConvertible};
@@ -55,10 +56,10 @@ use js::glue::{IsWrapper, UnwrapObjectDynamic};
 use js::glue::{RUST_JSID_IS_INT, RUST_JSID_TO_INT};
 use js::glue::{RUST_JSID_IS_STRING, RUST_JSID_TO_STRING};
 use js::jsapi::{Heap, JSContext, JSObject, JSString};
+use js::jsapi::{IsWindowProxy, JS_NewStringCopyN, JS_StringHasLatin1Chars};
 use js::jsapi::{
     JS_GetLatin1StringCharsAndLength, JS_GetTwoByteStringCharsAndLength, JS_IsExceptionPending,
 };
-use js::jsapi::{JS_NewStringCopyN, JS_StringHasLatin1Chars};
 use js::jsval::{ObjectValue, StringValue, UndefinedValue};
 use js::rust::wrappers::{JS_GetProperty, JS_HasProperty, JS_IsArrayObject};
 use js::rust::{get_object_class, is_dom_class, is_dom_object, maybe_wrap_value, ToString};
@@ -634,3 +635,22 @@ where
         Err(()) => Err(Error::JSFailed),
     }
 }
+
+/// Get a `DomRoot<T>` for a WindowProxy accessible from a `HandleValue`.
+/// Caller is responsible for throwing a JS exception if needed in case of error.
+pub unsafe fn windowproxy_from_handlevalue(
+    v: HandleValue,
+    _cx: *mut JSContext,
+) -> Result<DomRoot<WindowProxy>, ()> {
+    if !v.get().is_object() {
+        return Err(());
+    }
+    let object = v.get().to_object();
+    if !IsWindowProxy(object) {
+        return Err(());
+    }
+    let mut value = UndefinedValue();
+    GetProxyReservedSlot(object, 0, &mut value);
+    let ptr = value.to_private() as *const WindowProxy;
+    Ok(DomRoot::from_ref(&*ptr))
+}
diff --git a/components/script/dom/messageevent.rs b/components/script/dom/messageevent.rs
index cb8ebaaebd1..3e9a7079605 100644
--- a/components/script/dom/messageevent.rs
+++ b/components/script/dom/messageevent.rs
@@ -5,9 +5,10 @@
 use crate::dom::bindings::codegen::Bindings::EventBinding::EventMethods;
 use crate::dom::bindings::codegen::Bindings::MessageEventBinding;
 use crate::dom::bindings::codegen::Bindings::MessageEventBinding::MessageEventMethods;
+use crate::dom::bindings::codegen::UnionTypes::WindowProxyOrMessagePortOrServiceWorker;
 use crate::dom::bindings::error::Fallible;
 use crate::dom::bindings::inheritance::Castable;
-use crate::dom::bindings::reflector::{reflect_dom_object, DomObject};
+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;
@@ -16,14 +17,39 @@ use crate::dom::event::Event;
 use crate::dom::eventtarget::EventTarget;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::messageport::MessagePort;
+use crate::dom::serviceworker::ServiceWorker;
 use crate::dom::windowproxy::WindowProxy;
 use crate::script_runtime::JSContext;
 use dom_struct::dom_struct;
-use js::jsapi::{Heap, JSObject};
+use js::jsapi::Heap;
 use js::jsval::JSVal;
 use js::rust::HandleValue;
 use servo_atoms::Atom;
-use std::ptr::NonNull;
+
+#[must_root]
+#[derive(JSTraceable, MallocSizeOf)]
+enum SrcObject {
+    WindowProxy(Dom<WindowProxy>),
+    MessagePort(Dom<MessagePort>),
+    ServiceWorker(Dom<ServiceWorker>),
+}
+
+impl From<&WindowProxyOrMessagePortOrServiceWorker> for SrcObject {
+    #[allow(unrooted_must_root)]
+    fn from(src_object: &WindowProxyOrMessagePortOrServiceWorker) -> SrcObject {
+        match src_object {
+            WindowProxyOrMessagePortOrServiceWorker::WindowProxy(blob) => {
+                SrcObject::WindowProxy(Dom::from_ref(&*blob))
+            },
+            WindowProxyOrMessagePortOrServiceWorker::MessagePort(stream) => {
+                SrcObject::MessagePort(Dom::from_ref(&*stream))
+            },
+            WindowProxyOrMessagePortOrServiceWorker::ServiceWorker(stream) => {
+                SrcObject::ServiceWorker(Dom::from_ref(&*stream))
+            },
+        }
+    }
+}
 
 #[dom_struct]
 pub struct MessageEvent {
@@ -31,7 +57,7 @@ pub struct MessageEvent {
     #[ignore_malloc_size_of = "mozjs"]
     data: Heap<JSVal>,
     origin: DOMString,
-    source: Option<Dom<WindowProxy>>,
+    source: Option<SrcObject>,
     lastEventId: DOMString,
     ports: Vec<DomRoot<MessagePort>>,
 }
@@ -52,14 +78,14 @@ impl MessageEvent {
         global: &GlobalScope,
         data: HandleValue,
         origin: DOMString,
-        source: Option<&WindowProxy>,
+        source: Option<&WindowProxyOrMessagePortOrServiceWorker>,
         lastEventId: DOMString,
         ports: Vec<DomRoot<MessagePort>>,
     ) -> DomRoot<MessageEvent> {
         let ev = Box::new(MessageEvent {
             event: Event::new_inherited(),
             data: Heap::default(),
-            source: source.map(Dom::from_ref),
+            source: source.map(|source| source.into()),
             origin,
             lastEventId,
             ports,
@@ -77,7 +103,7 @@ impl MessageEvent {
         cancelable: bool,
         data: HandleValue,
         origin: DOMString,
-        source: Option<&WindowProxy>,
+        source: Option<&WindowProxyOrMessagePortOrServiceWorker>,
         lastEventId: DOMString,
         ports: Vec<DomRoot<MessagePort>>,
     ) -> DomRoot<MessageEvent> {
@@ -94,10 +120,6 @@ impl MessageEvent {
         type_: DOMString,
         init: RootedTraceableBox<MessageEventBinding::MessageEventInit>,
     ) -> Fallible<DomRoot<MessageEvent>> {
-        let source = init
-            .source
-            .as_ref()
-            .and_then(|inner| inner.as_ref().map(|source| source.window_proxy()));
         let ev = MessageEvent::new(
             global,
             Atom::from(type_),
@@ -105,9 +127,9 @@ impl MessageEvent {
             init.parent.cancelable,
             init.data.handle(),
             init.origin.clone(),
-            source.as_ref().map(|source| &**source),
+            init.source.as_ref(),
             init.lastEventId.clone(),
-            init.ports.clone().unwrap_or(vec![]),
+            init.ports.clone(),
         );
         Ok(ev)
     }
@@ -129,7 +151,11 @@ impl MessageEvent {
             false,
             message,
             DOMString::from(origin.unwrap_or("")),
-            source,
+            source
+                .map(|source| {
+                    WindowProxyOrMessagePortOrServiceWorker::WindowProxy(DomRoot::from_ref(source))
+                })
+                .as_ref(),
             DOMString::new(),
             ports,
         );
@@ -138,10 +164,6 @@ impl MessageEvent {
 
     pub fn dispatch_error(target: &EventTarget, scope: &GlobalScope) {
         let init = MessageEventBinding::MessageEventInit::empty();
-        let source = init
-            .source
-            .as_ref()
-            .and_then(|inner| inner.as_ref().map(|source| source.window_proxy()));
         let messageevent = MessageEvent::new(
             scope,
             atom!("messageerror"),
@@ -149,9 +171,9 @@ impl MessageEvent {
             init.parent.cancelable,
             init.data.handle(),
             init.origin.clone(),
-            source.as_ref().map(|source| &**source),
+            init.source.as_ref(),
             init.lastEventId.clone(),
-            init.ports.clone().unwrap_or(vec![]),
+            init.ports.clone(),
         );
         messageevent.upcast::<Event>().fire(target);
     }
@@ -169,10 +191,19 @@ impl MessageEventMethods for MessageEvent {
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-messageevent-source
-    fn GetSource(&self, _cx: JSContext) -> Option<NonNull<JSObject>> {
-        self.source
-            .as_ref()
-            .and_then(|source| NonNull::new(source.reflector().get_jsobject().get()))
+    fn GetSource(&self) -> Option<WindowProxyOrMessagePortOrServiceWorker> {
+        match &self.source {
+            Some(SrcObject::WindowProxy(i)) => Some(
+                WindowProxyOrMessagePortOrServiceWorker::WindowProxy(DomRoot::from_ref(&*i)),
+            ),
+            Some(SrcObject::MessagePort(i)) => Some(
+                WindowProxyOrMessagePortOrServiceWorker::MessagePort(DomRoot::from_ref(&*i)),
+            ),
+            Some(SrcObject::ServiceWorker(i)) => Some(
+                WindowProxyOrMessagePortOrServiceWorker::ServiceWorker(DomRoot::from_ref(&*i)),
+            ),
+            None => None,
+        }
     }
 
     /// <https://html.spec.whatwg.org/multipage/#dom-messageevent-lasteventid>
diff --git a/components/script/dom/webidls/MessageEvent.webidl b/components/script/dom/webidls/MessageEvent.webidl
index 63dd9019cc9..1d4699cbe3c 100644
--- a/components/script/dom/webidls/MessageEvent.webidl
+++ b/components/script/dom/webidls/MessageEvent.webidl
@@ -9,9 +9,7 @@ interface MessageEvent : Event {
   readonly attribute any data;
   readonly attribute DOMString origin;
   readonly attribute DOMString lastEventId;
-  // FIXME(#22617): WindowProxy is not exposed in Worker globals
-  readonly attribute object? source;
-  //readonly attribute (WindowProxy or MessagePort)? source;
+  readonly attribute MessageEventSource? source;
   readonly attribute /*FrozenArray<MessagePort>*/any ports;
 };
 
@@ -20,9 +18,8 @@ dictionary MessageEventInit : EventInit {
   DOMString origin = "";
   DOMString lastEventId = "";
   //DOMString channel;
-  Window? source;
-  //(WindowProxy or MessagePort)? source;
-  sequence<MessagePort> ports;
+  MessageEventSource? source = null;
+  sequence<MessagePort> ports = [];
 };
 
-typedef (/*WindowProxy or */MessagePort or ServiceWorker) MessageEventSource;
+typedef (WindowProxy or MessagePort or ServiceWorker) MessageEventSource;