Clean up the conversion routines

Functions returning `Root<T>` are prefixed by "root_" and the ones returning
`*const T` by "native_".

Functions taking `*mut JSObject` are now suffixed by "_from_object" and the ones
taking `&T` by "_from_reflector".

10 files changed, 45 insertions, 61 deletions

diff --git a/components/script/dom/bindings/callback.rs b/components/script/dom/bindings/callback.rs
index 1b067c5c596..182af6656b8 100644
--- a/components/script/dom/bindings/callback.rs
+++ b/components/script/dom/bindings/callback.rs
@@ -5,7 +5,7 @@
 //! Base classes to work with IDL callbacks.
 
 use dom::bindings::error::{Error, Fallible};
-use dom::bindings::global::global_object_for_js_object;
+use dom::bindings::global::global_root_from_object;
 use dom::bindings::reflector::Reflectable;
 use js::jsapi::GetGlobalForObjectCrossCompartment;
 use js::jsapi::{Heap, MutableHandleObject, RootedObject, RootedValue};
@@ -170,7 +170,7 @@ impl CallSetup {
     /// Performs the setup needed to make a call.
     #[allow(unrooted_must_root)]
     pub fn new<T: CallbackContainer>(callback: &T, handling: ExceptionHandling) -> CallSetup {
-        let global = global_object_for_js_object(callback.callback());
+        let global = global_root_from_object(callback.callback());
         let cx = global.r().get_cx();
         unsafe { JS_BeginRequest(cx); }
 
diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index 8e88b5cb2e1..d59330d7016 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -119,7 +119,7 @@ class CastableObjectUnwrapper():
 
     def __str__(self):
         return string.Template("""\
-match native_from_handle${handletype}(${source}) {
+match root_from_handle${handletype}(${source}) {
     Ok(val) => val,
     Err(()) => {
 ${codeOnFailure}
@@ -1996,7 +1996,7 @@ def UnionTypes(descriptors, dictionaries, callbacks, config):
         'dom::bindings::conversions::FromJSValConvertible',
         'dom::bindings::conversions::ToJSValConvertible',
         'dom::bindings::conversions::ConversionBehavior',
-        'dom::bindings::conversions::native_from_handlevalue',
+        'dom::bindings::conversions::root_from_handlevalue',
         'dom::bindings::conversions::StringificationBehavior',
         'dom::bindings::error::throw_not_in_union',
         'dom::bindings::js::Root',
@@ -2638,7 +2638,7 @@ class CGCallGenerator(CGThing):
             if static:
                 glob = ""
             else:
-                glob = "        let global = global_object_for_js_object(this.reflector().get_jsobject().get());\n"
+                glob = "        let global = global_root_from_reflector(this);\n"
 
             self.cgRoot.append(CGGeneric(
                 "let result = match result {\n"
@@ -2845,7 +2845,7 @@ class CGAbstractStaticBindingMethod(CGAbstractMethod):
 
     def definition_body(self):
         preamble = CGGeneric("""\
-let global = global_object_for_js_object(JS_CALLEE(cx, vp).to_object());
+let global = global_root_from_object(JS_CALLEE(cx, vp).to_object());
 """)
         return CGList([preamble, self.generate_code()])
 
@@ -4532,8 +4532,8 @@ class CGAbstractClassHook(CGAbstractExternMethod):
 
     def definition_body_prologue(self):
         return CGGeneric("""\
-let this: *const %s = native_from_reflector::<%s>(obj);
-""" % (self.descriptor.concreteType, self.descriptor.concreteType))
+let this = private_from_object(obj) as *const %s;
+""" % self.descriptor.concreteType)
 
     def definition_body(self):
         return CGList([
@@ -4593,7 +4593,7 @@ class CGClassConstructHook(CGAbstractExternMethod):
 
     def definition_body(self):
         preamble = CGGeneric("""\
-let global = global_object_for_js_object(JS_CALLEE(cx, vp).to_object());
+let global = global_root_from_object(JS_CALLEE(cx, vp).to_object());
 let args = CallArgs::from_vp(vp, argc);
 """)
         name = self._ctor.identifier.name
@@ -4617,7 +4617,7 @@ class CGClassNameConstructHook(CGAbstractExternMethod):
 
     def definition_body(self):
         preamble = CGGeneric("""\
-let global = global_object_for_js_object(JS_CALLEE(cx, vp).to_object());
+let global = global_root_from_object(JS_CALLEE(cx, vp).to_object());
 let args = CallArgs::from_vp(vp, argc);
 """)
         name = self._ctor.identifier.name
@@ -5196,8 +5196,7 @@ class CGBindingRoot(CGThing):
             'js::glue::AppendToAutoIdVector',
             'js::rust::GCMethods',
             'dom::bindings',
-            'dom::bindings::global::GlobalRef',
-            'dom::bindings::global::global_object_for_js_object',
+            'dom::bindings::global::{GlobalRef, global_root_from_object, global_root_from_reflector}',
             'dom::bindings::js::{JS, Root, RootedReference}',
             'dom::bindings::js::{OptionalRootedReference}',
             'dom::bindings::reflector::{Reflectable}',
@@ -5223,12 +5222,11 @@ class CGBindingRoot(CGThing):
             'dom::bindings::callback::{CallbackContainer,CallbackInterface,CallbackFunction}',
             'dom::bindings::callback::{CallSetup,ExceptionHandling}',
             'dom::bindings::callback::wrap_call_this_object',
-            'dom::bindings::conversions::{FromJSValConvertible, ToJSValConvertible, ConversionBehavior}',
-            'dom::bindings::conversions::{native_from_reflector, native_from_handlevalue, native_from_handleobject}',
-            'dom::bindings::conversions::DOM_OBJECT_SLOT',
-            'dom::bindings::conversions::IDLInterface',
-            'dom::bindings::conversions::jsid_to_str',
-            'dom::bindings::conversions::StringificationBehavior',
+            'dom::bindings::conversions::{ConversionBehavior, DOM_OBJECT_SLOT, IDLInterface}',
+            'dom::bindings::conversions::{FromJSValConvertible, StringificationBehavior}',
+            'dom::bindings::conversions::{ToJSValConvertible, jsid_to_str}',
+            'dom::bindings::conversions::{private_from_object, root_from_object}',
+            'dom::bindings::conversions::{root_from_handleobject, root_from_handlevalue}',
             'dom::bindings::codegen::{PrototypeList, RegisterBindings, UnionTypes}',
             'dom::bindings::codegen::Bindings::*',
             'dom::bindings::error::{Fallible, Error, ErrorResult}',
diff --git a/components/script/dom/bindings/conversions.rs b/components/script/dom/bindings/conversions.rs
index 98918e9d7ea..d43642ee7e2 100644
--- a/components/script/dom/bindings/conversions.rs
+++ b/components/script/dom/bindings/conversions.rs
@@ -32,7 +32,6 @@
 //! | sequences               | `Vec<T>`                         |
 //! | union types             | `T`                              |
 
-use core::nonzero::NonZero;
 use dom::bindings::error::throw_type_error;
 use dom::bindings::inheritance::Castable;
 use dom::bindings::js::Root;
@@ -657,7 +656,7 @@ pub fn is_dom_proxy(obj: *mut JSObject) -> bool {
 pub const DOM_OBJECT_SLOT: u32 = 0;
 
 /// Get the private pointer of a DOM object from a given reflector.
-unsafe fn private_from_reflector(obj: *mut JSObject) -> *const libc::c_void {
+pub unsafe fn private_from_object(obj: *mut JSObject) -> *const libc::c_void {
     let clasp = JS_GetClass(obj);
     let value = if is_dom_class(clasp) {
         JS_GetReservedSlot(obj, DOM_OBJECT_SLOT)
@@ -672,11 +671,6 @@ unsafe fn private_from_reflector(obj: *mut JSObject) -> *const libc::c_void {
     }
 }
 
-/// Get the DOM object from the given reflector.
-pub unsafe fn native_from_reflector<T>(obj: *mut JSObject) -> *const T {
-    private_from_reflector(obj) as *const T
-}
-
 /// Get the `DOMClass` from `obj`, or `Err(())` if `obj` is not a DOM object.
 pub unsafe fn get_dom_class(obj: *mut JSObject) -> Result<&'static DOMClass, ()> {
     use dom::bindings::utils::DOMJSClass;
@@ -727,7 +721,7 @@ pub unsafe fn private_from_proto_check<F>(mut obj: *mut JSObject, proto_check: F
 
     if proto_check(dom_class) {
         debug!("good prototype");
-        Ok(private_from_reflector(obj))
+        Ok(private_from_object(obj))
     } else {
         debug!("bad prototype");
         Err(())
@@ -740,28 +734,28 @@ pub unsafe fn private_from_proto_check<F>(mut obj: *mut JSObject, proto_check: F
 /// Returns Err(()) if `obj` is an opaque security wrapper or if the object is
 /// not a reflector for a DOM object of the given type (as defined by the
 /// proto_id and proto_depth).
-pub fn native_from_reflector_jsmanaged<T>(obj: *mut JSObject) -> Result<Root<T>, ()>
+pub fn root_from_object<T>(obj: *mut JSObject) -> Result<Root<T>, ()>
     where T: Reflectable + IDLInterface
 {
     unsafe {
-        private_from_proto_check(obj, T::derives).map(|obj| {
-            Root::new(NonZero::new(obj as *const T))
+        private_from_proto_check(obj, T::derives).map(|ptr| {
+            Root::from_ref(&*(ptr as *const T))
         })
     }
 }
 
-/// Get a Rooted<T> for a DOM object accessible from a HandleValue
-pub fn native_from_handlevalue<T>(v: HandleValue) -> Result<Root<T>, ()>
+/// Get a `Root<T>` for a DOM object accessible from a `HandleValue`.
+pub fn root_from_handlevalue<T>(v: HandleValue) -> Result<Root<T>, ()>
     where T: Reflectable + IDLInterface
 {
-    native_from_reflector_jsmanaged(v.get().to_object())
+    root_from_object(v.get().to_object())
 }
 
-/// Get a Rooted<T> for a DOM object accessible from a HandleObject
-pub fn native_from_handleobject<T>(obj: HandleObject) -> Result<Root<T>, ()>
+/// Get a `Root<T>` for a DOM object accessible from a `HandleObject`.
+pub fn root_from_handleobject<T>(obj: HandleObject) -> Result<Root<T>, ()>
     where T: Reflectable + IDLInterface
 {
-    native_from_reflector_jsmanaged(obj.get())
+    root_from_object(obj.get())
 }
 
 impl<T: Reflectable> ToJSValConvertible for Root<T> {
diff --git a/components/script/dom/bindings/global.rs b/components/script/dom/bindings/global.rs
index f8f24d862df..c2d1c07c3ae 100644
--- a/components/script/dom/bindings/global.rs
+++ b/components/script/dom/bindings/global.rs
@@ -9,7 +9,7 @@
 
 use devtools_traits::ScriptToDevtoolsControlMsg;
 use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
-use dom::bindings::conversions::native_from_reflector_jsmanaged;
+use dom::bindings::conversions::root_from_object;
 use dom::bindings::js::{JS, Root};
 use dom::bindings::reflector::{Reflectable, Reflector};
 use dom::window::{self, ScriptHelpers};
@@ -255,23 +255,23 @@ impl GlobalField {
 }
 
 /// Returns the global object of the realm that the given DOM object's reflector was created in.
-pub fn global_object_for_reflector<T: Reflectable>(reflector: &T) -> GlobalRoot {
-    global_object_for_js_object(*reflector.reflector().get_jsobject())
+pub fn global_root_from_reflector<T: Reflectable>(reflector: &T) -> GlobalRoot {
+    global_root_from_object(*reflector.reflector().get_jsobject())
 }
 
 /// Returns the global object of the realm that the given JS object was created in.
 #[allow(unrooted_must_root)]
-pub fn global_object_for_js_object(obj: *mut JSObject) -> GlobalRoot {
+pub fn global_root_from_object(obj: *mut JSObject) -> GlobalRoot {
     unsafe {
         let global = GetGlobalForObjectCrossCompartment(obj);
         let clasp = JS_GetClass(global);
         assert!(((*clasp).flags & (JSCLASS_IS_DOMJSCLASS | JSCLASS_IS_GLOBAL)) != 0);
-        match native_from_reflector_jsmanaged(global) {
+        match root_from_object(global) {
             Ok(window) => return GlobalRoot::Window(window),
             Err(_) => (),
         }
 
-        match native_from_reflector_jsmanaged(global) {
+        match root_from_object(global) {
             Ok(worker) => return GlobalRoot::Worker(worker),
             Err(_) => (),
         }
diff --git a/components/script/dom/bindings/utils.rs b/components/script/dom/bindings/utils.rs
index 9783a9f6539..45e7db81d08 100644
--- a/components/script/dom/bindings/utils.rs
+++ b/components/script/dom/bindings/utils.rs
@@ -6,12 +6,10 @@
 
 use dom::bindings::codegen::PrototypeList;
 use dom::bindings::codegen::PrototypeList::MAX_PROTO_CHAIN_LENGTH;
-use dom::bindings::conversions::native_from_handleobject;
-use dom::bindings::conversions::private_from_proto_check;
-use dom::bindings::conversions::{is_dom_class, jsstring_to_str, DOM_OBJECT_SLOT};
+use dom::bindings::conversions::{DOM_OBJECT_SLOT, is_dom_class, jsstring_to_str};
+use dom::bindings::conversions::{private_from_proto_check, root_from_handleobject};
 use dom::bindings::error::{throw_invalid_this, throw_type_error};
 use dom::bindings::inheritance::TopTypeId;
-use dom::bindings::js::Root;
 use dom::bindings::trace::trace_object;
 use dom::browsercontext;
 use dom::window;
@@ -625,9 +623,7 @@ pub static WRAP_CALLBACKS: JSWrapObjectCallbacks = JSWrapObjectCallbacks {
 /// Callback to outerize windows.
 pub unsafe extern fn outerize_global(_cx: *mut JSContext, obj: HandleObject) -> *mut JSObject {
     debug!("outerizing");
-    let win: Root<window::Window> = native_from_handleobject(obj).unwrap();
-    // FIXME(https://github.com/rust-lang/rust/issues/23338)
-    let win = win.r();
+    let win = root_from_handleobject::<window::Window>(obj).unwrap();
     let context = win.browsing_context();
     context.as_ref().unwrap().window_proxy()
 }
diff --git a/components/script/dom/browsercontext.rs b/components/script/dom/browsercontext.rs
index 72d48d51d45..af32ac270dd 100644
--- a/components/script/dom/browsercontext.rs
+++ b/components/script/dom/browsercontext.rs
@@ -2,8 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use dom::bindings::conversions::native_from_handleobject;
-use dom::bindings::conversions::{ToJSValConvertible};
+use dom::bindings::conversions::{ToJSValConvertible, root_from_handleobject};
 use dom::bindings::js::{JS, Root};
 use dom::bindings::proxyhandler::{fill_property_descriptor, get_property_descriptor};
 use dom::bindings::reflector::{Reflectable, Reflector};
@@ -113,7 +112,7 @@ unsafe fn GetSubframeWindow(cx: *mut JSContext, proxy: HandleObject, id: HandleI
     let index = get_array_index_from_id(cx, id);
     if let Some(index) = index {
         let target = RootedObject::new(cx, GetProxyPrivate(*proxy.ptr).to_object());
-        let win: Root<Window> = native_from_handleobject(target.handle()).unwrap();
+        let win = root_from_handleobject::<Window>(target.handle()).unwrap();
         let mut found = false;
         return win.IndexedGetter(index, &mut found);
     }
diff --git a/components/script/dom/eventdispatcher.rs b/components/script/dom/eventdispatcher.rs
index 589d5a53f8b..d27af697be9 100644
--- a/components/script/dom/eventdispatcher.rs
+++ b/components/script/dom/eventdispatcher.rs
@@ -5,7 +5,7 @@
 use devtools_traits::{StartedTimelineMarker, TimelineMarker, TimelineMarkerType};
 use dom::bindings::callback::ExceptionHandling::Report;
 use dom::bindings::codegen::Bindings::EventBinding::EventMethods;
-use dom::bindings::global::{GlobalRoot, global_object_for_reflector};
+use dom::bindings::global::{GlobalRoot, global_root_from_reflector};
 use dom::bindings::inheritance::Castable;
 use dom::bindings::js::{JS, Root, RootedReference};
 use dom::bindings::trace::RootedVec;
@@ -49,7 +49,7 @@ fn dispatch_to_listeners(event: &Event, target: &EventTarget, chain: &[&EventTar
     assert!(!event.stop_propagation());
     assert!(!event.stop_immediate());
 
-    let window = match global_object_for_reflector(target) {
+    let window = match global_root_from_reflector(target) {
         GlobalRoot::Window(window) => {
             if window.need_emit_timeline_marker(TimelineMarkerType::DOMEvent) {
                 Some(window)
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 3a8baa399d2..b1c58dcaeab 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -933,7 +933,7 @@ pub fn from_untrusted_node_address(_runtime: *mut JSRuntime, candidate: Untruste
         if object.is_null() {
             panic!("Attempted to create a `JS<Node>` from an invalid pointer!")
         }
-        let boxed_node: *const Node = conversions::native_from_reflector(object);
+        let boxed_node = conversions::private_from_object(object) as *const Node;
         Root::from_ref(&*boxed_node)
     }
 }
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 4da6bd76645..c7f0af1b234 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -12,8 +12,7 @@ use dom::bindings::codegen::Bindings::FunctionBinding::Function;
 use dom::bindings::codegen::Bindings::WindowBinding::{ScrollBehavior, ScrollToOptions};
 use dom::bindings::codegen::Bindings::WindowBinding::{self, FrameRequestCallback, WindowMethods};
 use dom::bindings::error::{Error, Fallible, report_pending_exception};
-use dom::bindings::global::GlobalRef;
-use dom::bindings::global::global_object_for_js_object;
+use dom::bindings::global::{GlobalRef, global_root_from_reflector};
 use dom::bindings::inheritance::Castable;
 use dom::bindings::js::RootedReference;
 use dom::bindings::js::{JS, MutNullableHeap, Root};
@@ -766,8 +765,7 @@ impl<'a, T: Reflectable> ScriptHelpers for &'a T {
     #[allow(unsafe_code)]
     fn evaluate_script_on_global_with_result(self, code: &str, filename: &str,
                                              rval: MutableHandleValue) {
-        let this = self.reflector().get_jsobject();
-        let global = global_object_for_js_object(this.get());
+        let global = global_root_from_reflector(self);
         let cx = global.r().get_cx();
         let _ar = JSAutoRequest::new(cx);
         let globalhandle = global.r().reflector().get_jsobject();
diff --git a/components/script/timers.rs b/components/script/timers.rs
index 2fd39c189f8..b2829b0f512 100644
--- a/components/script/timers.rs
+++ b/components/script/timers.rs
@@ -5,7 +5,7 @@
 use dom::bindings::callback::ExceptionHandling::Report;
 use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::FunctionBinding::Function;
-use dom::bindings::global::global_object_for_js_object;
+use dom::bindings::global::global_root_from_reflector;
 use dom::bindings::reflector::Reflectable;
 use dom::bindings::trace::JSTraceable;
 use dom::window::ScriptHelpers;
@@ -285,8 +285,7 @@ impl ActiveTimers {
             // step 14
             match callback {
                 InternalTimerCallback::StringTimerCallback(code_str) => {
-                    let proxy = this.reflector().get_jsobject();
-                    let cx = global_object_for_js_object(proxy.get()).r().get_cx();
+                    let cx = global_root_from_reflector(this).r().get_cx();
                     let mut rval = RootedValue::new(cx, UndefinedValue());
 
                     this.evaluate_js_on_global_with_result(&code_str, rval.handle_mut());