Auto merge of #13194 - servo:mutreflectable, r=Ms2ger

Extract mutability out of Reflectable trait.

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components/plugins/reflector.rs

@@ -24,12 +24,17 @@ pub fn expand_reflector(cx: &mut ExtCtxt, span: Span, _: &MetaItem, annotatable:
                             fn reflector<'a>(&'a self) -> &'a ::dom::bindings::reflector::Reflector {
                                 &self.$field_name
                             }
+                        }
+                    );
+                    let impl_item_mut = quote_item!(cx,
+                        impl ::dom::bindings::reflector::MutReflectable for $struct_name {
                             fn init_reflector(&mut self, obj: *mut ::js::jsapi::JSObject) {
                                 self.$field_name.set_jsobject(obj);
                             }
                         }
                     );
-                    impl_item.map(|it| push(Annotatable::Item(it)))
+                    impl_item.map(|it| push(Annotatable::Item(it)));
+                    impl_item_mut.map(|it| push(Annotatable::Item(it)))
                 },
                 // Or just call it on the first field (supertype).
                 None => {
@@ -39,12 +44,17 @@ pub fn expand_reflector(cx: &mut ExtCtxt, span: Span, _: &MetaItem, annotatable:
                             fn reflector<'a>(&'a self) -> &'a ::dom::bindings::reflector::Reflector {
                                 self.$field_name.reflector()
                             }
+                        }
+                    );
+                    let impl_item_mut = quote_item!(cx,
+                        impl ::dom::bindings::reflector::MutReflectable for $struct_name {
                             fn init_reflector(&mut self, obj: *mut ::js::jsapi::JSObject) {
                                 self.$field_name.init_reflector(obj);
                             }
                         }
                     );
-                    impl_item.map(|it| push(Annotatable::Item(it)))
+                    impl_item.map(|it| push(Annotatable::Item(it)));
+                    impl_item_mut.map(|it| push(Annotatable::Item(it)))
                 }
             };
 

components/script/devtools.rs

@@ -16,6 +16,7 @@ use dom::bindings::conversions::{ConversionResult, FromJSValConvertible, jsstrin
 use dom::bindings::global::GlobalRef;
 use dom::bindings::inheritance::Castable;
 use dom::bindings::js::Root;
+use dom::bindings::reflector::Reflectable;
 use dom::bindings::str::DOMString;
 use dom::browsingcontext::BrowsingContext;
 use dom::element::Element;

components/script/dom/bindings/codegen/CodegenRust.py

@@ -5452,6 +5452,7 @@ def generate_imports(config, cgthings, descriptors, callbacks=None, dictionaries
         'dom::bindings::js::OptionalRootedReference',
         'dom::bindings::js::Root',
         'dom::bindings::js::RootedReference',
+        'dom::bindings::reflector::MutReflectable',
         'dom::bindings::reflector::Reflectable',
         'dom::bindings::utils::DOMClass',
         'dom::bindings::utils::DOMJSClass',

components/script/dom/bindings/global.rs

@@ -271,14 +271,6 @@ impl<'a> GlobalRef<'a> {
         }
     }
 
-    /// Returns the receiver's reflector.
-    pub fn reflector(&self) -> &Reflector {
-        match *self {
-            GlobalRef::Window(ref window) => window.reflector(),
-            GlobalRef::Worker(ref worker) => worker.reflector(),
-        }
-    }
-
     /// Returns a wrapper for runnables to ensure they are cancelled if the global
     /// is being destroyed.
     pub fn get_runnable_wrapper(&self) -> RunnableWrapper {
@@ -297,6 +289,15 @@ impl<'a> GlobalRef<'a> {
     }
 }
 
+impl<'a> Reflectable for GlobalRef<'a> {
+    fn reflector(&self) -> &Reflector {
+        match *self {
+            GlobalRef::Window(ref window) => window.reflector(),
+            GlobalRef::Worker(ref worker) => worker.reflector(),
+        }
+    }
+}
+
 impl GlobalRoot {
     /// Obtain a safe reference to the global object that cannot outlive the
     /// lifetime of this root.

components/script/dom/bindings/iterable.rs

@@ -12,7 +12,7 @@ use dom::bindings::codegen::Bindings::IterableIteratorBinding::IterableKeyOrValu
 use dom::bindings::error::Fallible;
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{JS, Root};
-use dom::bindings::reflector::{Reflector, Reflectable, reflect_dom_object};
+use dom::bindings::reflector::{Reflector, Reflectable, MutReflectable, reflect_dom_object};
 use dom::bindings::trace::JSTraceable;
 use js::conversions::ToJSValConvertible;
 use js::jsapi::{JSContext, JSObject, MutableHandleValue, MutableHandleObject, HandleValue};
@@ -63,6 +63,9 @@ impl<T: Reflectable + JSTraceable + Iterable> Reflectable for IterableIterator<T
     fn reflector<'a>(&'a self) -> &'a Reflector {
         &self.reflector
     }
+}
+
+impl<T: Reflectable + JSTraceable + Iterable> MutReflectable for IterableIterator<T> {
     fn init_reflector(&mut self, obj: *mut JSObject) {
         self.reflector.set_jsobject(obj);
     }

components/script/dom/bindings/reflector.rs

@@ -73,11 +73,15 @@ impl Reflector {
 pub trait Reflectable {
     /// Returns the receiver's reflector.
     fn reflector(&self) -> &Reflector;
-    /// Initializes the Reflector
-    fn init_reflector(&mut self, obj: *mut JSObject);
 
     /// Returns the global object of the realm that the Reflectable was created in.
     fn global(&self) -> GlobalRoot where Self: Sized {
         global_root_from_reflector(self)
     }
 }
+
+/// A trait to initialize the `Reflector` for a DOM object.
+pub trait MutReflectable: Reflectable {
+    /// Initializes the Reflector
+    fn init_reflector(&mut self, obj: *mut JSObject);
+}

components/script/dom/browsingcontext.rs

@@ -7,7 +7,7 @@ use dom::bindings::codegen::Bindings::DocumentBinding::DocumentMethods;
 use dom::bindings::conversions::{ToJSValConvertible, root_from_handleobject};
 use dom::bindings::js::{JS, Root, RootedReference};
 use dom::bindings::proxyhandler::{fill_property_descriptor, get_property_descriptor};
-use dom::bindings::reflector::{Reflectable, Reflector};
+use dom::bindings::reflector::{Reflectable, MutReflectable, Reflector};
 use dom::bindings::str::DOMString;
 use dom::bindings::trace::JSTraceable;
 use dom::bindings::utils::WindowProxyHandler;