Move various reflector types and traits to script_bindings (#35279)

* script: Move Reflector to script_bindings.

Signed-off-by: Josh Matthews <josh@joshmatthews.net>

* script: Extract global() helper from DomObject into new trait. Move DomObject and related traits to script_bindings.

Signed-off-by: Josh Matthews <josh@joshmatthews.net>

---------

Signed-off-by: Josh Matthews <josh@joshmatthews.net>

components/script/dom/bindings/callback.rs

@@ -15,12 +15,11 @@ use js::jsapi::{
 };
 use js::jsval::{JSVal, ObjectValue, UndefinedValue};
 use js::rust::wrappers::{JS_GetProperty, JS_WrapObject};
-use js::rust::{HandleObject, MutableHandleObject, Runtime};
+use js::rust::{MutableHandleObject, Runtime};
 
 use crate::dom::bindings::codegen::Bindings::WindowBinding::Window_Binding::WindowMethods;
 use crate::dom::bindings::error::{report_pending_exception, Error, Fallible};
 use crate::dom::bindings::inheritance::Castable;
-use crate::dom::bindings::reflector::DomObject;
 use crate::dom::bindings::root::{Dom, DomRoot};
 use crate::dom::bindings::settings_stack::{AutoEntryScript, AutoIncumbentScript};
 use crate::dom::bindings::utils::AsCCharPtrPtr;
@@ -206,21 +205,7 @@ impl CallbackInterface {
     }
 }
 
-pub(crate) trait ThisReflector {
-    fn jsobject(&self) -> *mut JSObject;
-}
-
-impl<T: DomObject> ThisReflector for T {
-    fn jsobject(&self) -> *mut JSObject {
-        self.reflector().get_jsobject().get()
-    }
-}
-
-impl ThisReflector for HandleObject<'_> {
-    fn jsobject(&self) -> *mut JSObject {
-        self.get()
-    }
-}
+pub(crate) use script_bindings::callback::ThisReflector;
 
 /// Wraps the reflector for `p` into the realm of `cx`.
 pub(crate) fn wrap_call_this_object<T: ThisReflector>(

components/script/dom/bindings/conversions.rs

@@ -40,11 +40,11 @@ pub(crate) use js::conversions::{
 use js::error::throw_type_error;
 use js::glue::{GetProxyReservedSlot, IsWrapper, JS_GetReservedSlot, UnwrapObjectDynamic};
 use js::jsapi::{Heap, IsWindowProxy, JSContext, JSObject, JS_IsExceptionPending};
-use js::jsval::{ObjectValue, UndefinedValue};
+use js::jsval::UndefinedValue;
 use js::rust::wrappers::{IsArrayObject, JS_GetProperty, JS_HasProperty};
 use js::rust::{
-    get_object_class, is_dom_class, is_dom_object, maybe_wrap_value, HandleId, HandleObject,
-    HandleValue, MutableHandleValue,
+    get_object_class, is_dom_class, is_dom_object, HandleId, HandleObject, HandleValue,
+    MutableHandleValue,
 };
 use num_traits::Float;
 pub(crate) use script_bindings::conversions::*;
@@ -52,7 +52,7 @@ pub(crate) use script_bindings::conversions::*;
 use crate::dom::bindings::error::{Error, Fallible};
 use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::num::Finite;
-use crate::dom::bindings::reflector::{DomObject, Reflector};
+use crate::dom::bindings::reflector::DomObject;
 use crate::dom::bindings::root::DomRoot;
 use crate::dom::bindings::str::DOMString;
 use crate::dom::bindings::trace::{JSTraceable, RootedTraceableBox};
@@ -169,15 +169,6 @@ pub(crate) unsafe fn jsid_to_string(cx: *mut JSContext, id: HandleId) -> Option<
     None
 }
 
-impl ToJSValConvertible for Reflector {
-    unsafe fn to_jsval(&self, cx: *mut JSContext, mut rval: MutableHandleValue) {
-        let obj = self.get_jsobject().get();
-        assert!(!obj.is_null());
-        rval.set(ObjectValue(obj));
-        maybe_wrap_value(cx, rval);
-    }
-}
-
 /// Returns whether `obj` is a DOM object implemented as a proxy.
 pub(crate) fn is_dom_proxy(obj: *mut JSObject) -> bool {
     use js::glue::IsProxyHandlerFamily;

components/script/dom/bindings/import.rs

@@ -35,7 +35,7 @@ pub(crate) mod base {
     pub(crate) use crate::dom::bindings::error::{throw_dom_exception, Fallible};
     pub(crate) use crate::dom::bindings::num::Finite;
     pub(crate) use crate::dom::bindings::proxyhandler::CrossOriginProperties;
-    pub(crate) use crate::dom::bindings::reflector::DomObject;
+    pub(crate) use crate::dom::bindings::reflector::{DomGlobal, DomObject};
     pub(crate) use crate::dom::bindings::root::DomRoot;
     pub(crate) use crate::dom::bindings::str::{ByteString, DOMString, USVString};
     pub(crate) use crate::dom::bindings::trace::RootedTraceableBox;

components/script/dom/bindings/iterable.rs

@@ -21,7 +21,7 @@ use crate::dom::bindings::codegen::Bindings::IterableIteratorBinding::{
 };
 use crate::dom::bindings::error::Fallible;
 use crate::dom::bindings::reflector::{
-    reflect_dom_object, DomObjectIteratorWrap, DomObjectWrap, Reflector,
+    reflect_dom_object, DomGlobal, DomObjectIteratorWrap, DomObjectWrap, Reflector,
 };
 use crate::dom::bindings::root::{Dom, DomRoot, Root};
 use crate::dom::bindings::trace::{JSTraceable, RootedTraceableBox};

components/script/dom/bindings/reflector.rs

@@ -4,9 +4,6 @@
 
 //! The `Reflector` struct.
 
-use std::default::Default;
-
-use js::jsapi::{Heap, JSObject};
 use js::rust::HandleObject;
 
 use crate::dom::bindings::conversions::DerivedFrom;
@@ -42,64 +39,7 @@ where
     unsafe { T::WRAP(GlobalScope::get_cx(), global_scope, proto, obj, can_gc) }
 }
 
-/// A struct to store a reference to the reflector of a DOM object.
-#[cfg_attr(crown, allow(crown::unrooted_must_root))]
-#[derive(MallocSizeOf)]
-#[cfg_attr(crown, crown::unrooted_must_root_lint::must_root)]
-// If you're renaming or moving this field, update the path in plugins::reflector as well
-pub(crate) struct Reflector {
-    #[ignore_malloc_size_of = "defined and measured in rust-mozjs"]
-    object: Heap<*mut JSObject>,
-}
-
-#[cfg_attr(crown, allow(crown::unrooted_must_root))]
-impl PartialEq for Reflector {
-    fn eq(&self, other: &Reflector) -> bool {
-        self.object.get() == other.object.get()
-    }
-}
-
-impl Reflector {
-    /// Get the reflector.
-    #[inline]
-    pub(crate) fn get_jsobject(&self) -> HandleObject {
-        // We're rooted, so it's safe to hand out a handle to object in Heap
-        unsafe { HandleObject::from_raw(self.object.handle()) }
-    }
-
-    /// Initialize the reflector. (May be called only once.)
-    ///
-    /// # Safety
-    ///
-    /// The provided [`JSObject`] pointer must point to a valid [`JSObject`].
-    pub(crate) unsafe fn set_jsobject(&self, object: *mut JSObject) {
-        assert!(self.object.get().is_null());
-        assert!(!object.is_null());
-        self.object.set(object);
-    }
-
-    /// Return a pointer to the memory location at which the JS reflector
-    /// object is stored. Used to root the reflector, as
-    /// required by the JSAPI rooting APIs.
-    pub(crate) fn rootable(&self) -> &Heap<*mut JSObject> {
-        &self.object
-    }
-
-    /// Create an uninitialized `Reflector`.
-    // These are used by the bindings and do not need `default()` functions.
-    #[allow(clippy::new_without_default)]
-    pub(crate) fn new() -> Reflector {
-        Reflector {
-            object: Heap::default(),
-        }
-    }
-}
-
-/// A trait to provide access to the `Reflector` for a DOM object.
-pub(crate) trait DomObject: JSTraceable + 'static {
-    /// Returns the receiver's reflector.
-    fn reflector(&self) -> &Reflector;
-
+pub trait DomGlobal: DomObject {
     /// Returns the [`GlobalScope`] of the realm that the [`DomObject`] was created in.  If this
     /// object is a `Node`, this will be different from it's owning `Document` if adopted by. For
     /// `Node`s it's almost always better to use `NodeTraits::owning_global`.
@@ -112,27 +52,9 @@ pub(crate) trait DomObject: JSTraceable + 'static {
     }
 }
 
-impl DomObject for Reflector {
-    fn reflector(&self) -> &Self {
-        self
-    }
-}
+impl<T: DomObject> DomGlobal for T {}
 
-/// A trait to initialize the `Reflector` for a DOM object.
-pub(crate) trait MutDomObject: DomObject {
-    /// Initializes the Reflector
-    ///
-    /// # Safety
-    ///
-    /// The provided [`JSObject`] pointer must point to a valid [`JSObject`].
-    unsafe fn init_reflector(&self, obj: *mut JSObject);
-}
-
-impl MutDomObject for Reflector {
-    unsafe fn init_reflector(&self, obj: *mut JSObject) {
-        self.set_jsobject(obj)
-    }
-}
+pub(crate) use script_bindings::reflector::{DomObject, MutDomObject, Reflector};
 
 /// A trait to provide a function pointer to wrap function for DOM objects.
 pub(crate) trait DomObjectWrap: Sized + DomObject {

components/script/dom/bindings/trace.rs

@@ -255,8 +255,6 @@ unsafe_no_jsmanaged_fields!(Box<dyn TaskBox>);
 
 unsafe_no_jsmanaged_fields!(IncompleteParserContexts);
 
-unsafe_no_jsmanaged_fields!(Reflector);
-
 #[allow(dead_code)]
 /// Trace a `JSScript`.
 pub(crate) fn trace_script(tracer: *mut JSTracer, description: &str, script: &Heap<*mut JSScript>) {