Auto merge of #20615 - KiChjang:window-indexed-getter, r=emilio

Implement window indexed getter

Fixes #4589.

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components/script/dom/dissimilaroriginwindow.rs

@@ -77,22 +77,26 @@ impl DissimilarOriginWindow {
     pub fn origin(&self) -> &MutableOrigin {
         self.upcast::<GlobalScope>().origin()
     }
+
+    pub fn window_proxy(&self) -> DomRoot<WindowProxy> {
+        DomRoot::from_ref(&*self.window_proxy)
+    }
 }
 
 impl DissimilarOriginWindowMethods for DissimilarOriginWindow {
     // https://html.spec.whatwg.org/multipage/#dom-window
     fn Window(&self) -> DomRoot<WindowProxy> {
-        DomRoot::from_ref(&*self.window_proxy)
+        self.window_proxy()
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-self
     fn Self_(&self) -> DomRoot<WindowProxy> {
-        DomRoot::from_ref(&*self.window_proxy)
+        self.window_proxy()
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-frames
     fn Frames(&self) -> DomRoot<WindowProxy> {
-        DomRoot::from_ref(&*self.window_proxy)
+        self.window_proxy()
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-parent

components/script/dom/document.rs

@@ -3792,7 +3792,7 @@ impl DocumentMethods for Document {
         let y = *y as f32;
         let point = &Point2D::new(x, y);
         let window = window_from_node(self);
-        let viewport = window.window_size().unwrap().initial_viewport;
+        let viewport = window.window_size()?.initial_viewport;
 
         if self.browsing_context().is_none() {
             return None;
@@ -3826,7 +3826,10 @@ impl DocumentMethods for Document {
         let y = *y as f32;
         let point = &Point2D::new(x, y);
         let window = window_from_node(self);
-        let viewport = window.window_size().unwrap().initial_viewport;
+        let viewport = match window.window_size() {
+            Some(size) => size.initial_viewport,
+            None => return vec![]
+        };
 
         if self.browsing_context().is_none() {
             return vec!();

components/script/dom/window.rs

@@ -1649,11 +1649,6 @@ impl Window {
         had_clip_rect
     }
 
-    // https://html.spec.whatwg.org/multipage/#accessing-other-browsing-contexts
-    pub fn IndexedGetter(&self, _index: u32, _found: &mut bool) -> Option<DomRoot<Window>> {
-        None
-    }
-
     pub fn suspend(&self) {
         // Suspend timer events.
         self.upcast::<GlobalScope>().suspend();

components/script/dom/windowproxy.rs

@@ -17,11 +17,12 @@ use dom::element::Element;
 use dom::globalscope::GlobalScope;
 use dom::window::Window;
 use dom_struct::dom_struct;
+use ipc_channel::ipc;
 use js::JSCLASS_IS_GLOBAL;
 use js::glue::{CreateWrapperProxyHandler, ProxyTraps};
 use js::glue::{GetProxyPrivate, SetProxyExtra, GetProxyExtra};
 use js::jsapi::{JSAutoCompartment, JSContext, JSErrNum, JSFreeOp, JSObject};
-use js::jsapi::{JSPROP_READONLY, JSTracer, JS_DefinePropertyById};
+use js::jsapi::{JSPROP_ENUMERATE, JSPROP_READONLY, JSTracer, JS_DefinePropertyById};
 use js::jsapi::{JS_ForwardGetPropertyTo, JS_ForwardSetPropertyTo};
 use js::jsapi::{JS_HasPropertyById, JS_HasOwnPropertyById};
 use js::jsapi::{JS_IsExceptionPending, JS_GetOwnPropertyDescriptorById};
@@ -40,6 +41,8 @@ use js::rust::wrappers::{NewWindowProxy, SetWindowProxy, JS_TransplantObject};
 use msg::constellation_msg::BrowsingContextId;
 use msg::constellation_msg::PipelineId;
 use msg::constellation_msg::TopLevelBrowsingContextId;
+use script_thread::ScriptThread;
+use script_traits::ScriptMsg;
 use std::cell::Cell;
 use std::ptr;
 
@@ -301,17 +304,45 @@ impl WindowProxy {
 
 // This is only called from extern functions,
 // there's no use using the lifetimed handles here.
+// https://html.spec.whatwg.org/multipage/#accessing-other-browsing-contexts
 #[allow(unsafe_code)]
-unsafe fn GetSubframeWindow(cx: *mut JSContext,
-                            proxy: RawHandleObject,
-                            id: RawHandleId)
-                            -> Option<DomRoot<Window>> {
+unsafe fn GetSubframeWindowProxy(
+    cx: *mut JSContext,
+    proxy: RawHandleObject,
+    id: RawHandleId
+) -> Option<(DomRoot<WindowProxy>, u32)> {
     let index = get_array_index_from_id(cx, Handle::from_raw(id));
     if let Some(index) = index {
         rooted!(in(cx) let target = GetProxyPrivate(*proxy).to_object());
-        let win = root_from_handleobject::<Window>(target.handle()).unwrap();
-        let mut found = false;
-        return win.IndexedGetter(index, &mut found);
+        if let Ok(win) = root_from_handleobject::<Window>(target.handle()) {
+            let browsing_context_id = win.window_proxy().browsing_context_id();
+            let (result_sender, result_receiver) = ipc::channel().unwrap();
+
+            let _ = win.upcast::<GlobalScope>().script_to_constellation_chan().send(
+                ScriptMsg::GetChildBrowsingContextId(
+                    browsing_context_id,
+                    index as usize,
+                    result_sender
+                )
+            );
+            return result_receiver.recv().ok()
+                .and_then(|maybe_bcid| maybe_bcid)
+                .and_then(ScriptThread::find_window_proxy)
+                .map(|proxy| (proxy, JSPROP_ENUMERATE | JSPROP_READONLY));
+        } else if let Ok(win) = root_from_handleobject::<DissimilarOriginWindow>(target.handle()) {
+            let browsing_context_id = win.window_proxy().browsing_context_id();
+            let (result_sender, result_receiver) = ipc::channel().unwrap();
+
+            let _ = win.global().script_to_constellation_chan().send(ScriptMsg::GetChildBrowsingContextId(
+                browsing_context_id,
+                index as usize,
+                result_sender
+            ));
+            return result_receiver.recv().ok()
+                .and_then(|maybe_bcid| maybe_bcid)
+                .and_then(ScriptThread::find_window_proxy)
+                .map(|proxy| (proxy, JSPROP_READONLY));
+        }
     }
 
     None
@@ -323,12 +354,12 @@ unsafe extern "C" fn getOwnPropertyDescriptor(cx: *mut JSContext,
                                               id: RawHandleId,
                                               mut desc: RawMutableHandle<PropertyDescriptor>)
                                               -> bool {
-    let window = GetSubframeWindow(cx, proxy, id);
-    if let Some(window) = window {
+    let window = GetSubframeWindowProxy(cx, proxy, id);
+    if let Some((window, attrs)) = window {
         rooted!(in(cx) let mut val = UndefinedValue());
         window.to_jsval(cx, val.handle_mut());
         desc.value = val.get();
-        fill_property_descriptor(MutableHandle::from_raw(desc), proxy.get(), JSPROP_READONLY);
+        fill_property_descriptor(MutableHandle::from_raw(desc), proxy.get(), attrs);
         return true;
     }
 
@@ -372,7 +403,7 @@ unsafe extern "C" fn has(cx: *mut JSContext,
                          id: RawHandleId,
                          bp: *mut bool)
                          -> bool {
-    let window = GetSubframeWindow(cx, proxy, id);
+    let window = GetSubframeWindowProxy(cx, proxy, id);
     if window.is_some() {
         *bp = true;
         return true;
@@ -395,8 +426,8 @@ unsafe extern "C" fn get(cx: *mut JSContext,
                          id: RawHandleId,
                          vp: RawMutableHandleValue)
                          -> bool {
-    let window = GetSubframeWindow(cx, proxy, id);
-    if let Some(window) = window {
+    let window = GetSubframeWindowProxy(cx, proxy, id);
+    if let Some((window, _attrs)) = window {
         window.to_jsval(cx, MutableHandle::from_raw(vp));
         return true;
     }