Make stylesheets block page load.

components/script/document_loader.rs

@@ -7,11 +7,10 @@
 
 use script_task::{ScriptMsg, ScriptChan};
 use msg::constellation_msg::{PipelineId};
-use net_traits::{LoadResponse, Metadata, load_whole_resource, ResourceTask};
-use net_traits::{ControlMsg, LoadData, LoadConsumer};
+use net_traits::{LoadResponse, Metadata, load_whole_resource, ResourceTask, PendingAsyncLoad};
 use url::Url;
 
-use std::sync::mpsc::{Receiver, channel};
+use std::sync::mpsc::Receiver;
 
 #[jstraceable]
 #[derive(PartialEq, Clone)]
@@ -69,15 +68,21 @@ impl DocumentLoader {
         }
     }
 
-    pub fn load_async(&mut self, load: LoadType) -> Receiver<LoadResponse> {
-        let (tx, rx) = channel();
+    /// Create a new pending network request, which can be initiated at some point in
+    /// the future.
+    pub fn prep_async_load(&mut self, load: LoadType) -> PendingAsyncLoad {
         self.blocking_loads.push(load.clone());
         let pipeline = self.notifier_data.as_ref().map(|data| data.pipeline);
-        let load_data = LoadData::new(load.url().clone(), pipeline);
-        self.resource_task.send(ControlMsg::Load(load_data, LoadConsumer::Channel(tx))).unwrap();
-        rx
+        PendingAsyncLoad::new(self.resource_task.clone(), load.url().clone(), pipeline)
     }
 
+    /// Create and initiate a new network request.
+    pub fn load_async(&mut self, load: LoadType) -> Receiver<LoadResponse> {
+        let pending = self.prep_async_load(load);
+        pending.load()
+    }
+
+    /// Create, initiate, and await the response for a new network request.
     pub fn load_sync(&mut self, load: LoadType) -> Result<(Metadata, Vec<u8>), String> {
         self.blocking_loads.push(load.clone());
         let result = load_whole_resource(&self.resource_task, load.url().clone());
@@ -85,6 +90,7 @@ impl DocumentLoader {
         result
     }
 
+    /// Mark an in-progress network request complete.
     pub fn finish_load(&mut self, load: LoadType) {
         let idx = self.blocking_loads.iter().position(|unfinished| *unfinished == load);
         self.blocking_loads.remove(idx.expect("unknown completed load"));

components/script/dom/document.rs

@@ -72,7 +72,7 @@ use msg::constellation_msg::{ConstellationChan, FocusType, Key, KeyState, KeyMod
 use msg::constellation_msg::{SUPER, ALT, SHIFT, CONTROL};
 use net_traits::CookieSource::NonHTTP;
 use net_traits::ControlMsg::{SetCookiesForUrl, GetCookiesForUrl};
-use net_traits::{Metadata, LoadResponse};
+use net_traits::{Metadata, LoadResponse, PendingAsyncLoad};
 use script_task::Runnable;
 use script_traits::{MouseButton, UntrustedNodeAddress};
 use util::opts;
@@ -260,6 +260,7 @@ pub trait DocumentHelpers<'a> {
     fn cancel_animation_frame(self, ident: i32);
     /// http://w3c.github.io/animation-timing/#dfn-invoke-callbacks-algorithm
     fn invoke_animation_callbacks(self);
+    fn prep_async_load(self, load: LoadType) -> PendingAsyncLoad;
     fn load_async(self, load: LoadType) -> Receiver<LoadResponse>;
     fn load_sync(self, load: LoadType) -> Result<(Metadata, Vec<u8>), String>;
     fn finish_load(self, load: LoadType);
@@ -884,6 +885,11 @@ impl<'a> DocumentHelpers<'a> for JSRef<'a, Document> {
         }
     }
 
+    fn prep_async_load(self, load: LoadType) -> PendingAsyncLoad {
+        let mut loader = self.loader.borrow_mut();
+        loader.prep_async_load(load)
+    }
+
     fn load_async(self, load: LoadType) -> Receiver<LoadResponse> {
         let mut loader = self.loader.borrow_mut();
         loader.load_async(load)

components/script/dom/htmllinkelement.rs

@@ -2,15 +2,17 @@
  * 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 document_loader::LoadType;
 use dom::attr::{Attr, AttrValue};
 use dom::attr::AttrHelpers;
 use dom::bindings::codegen::Bindings::HTMLLinkElementBinding;
 use dom::bindings::codegen::Bindings::HTMLLinkElementBinding::HTMLLinkElementMethods;
+use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
 use dom::bindings::codegen::InheritTypes::HTMLLinkElementDerived;
 use dom::bindings::codegen::InheritTypes::{ElementCast, HTMLElementCast, NodeCast};
 use dom::bindings::js::{JS, JSRef, MutNullableHeap, Rootable, Temporary};
 use dom::bindings::js::{OptionalRootable, RootedReference};
-use dom::document::Document;
+use dom::document::{Document, DocumentHelpers};
 use dom::domtokenlist::DOMTokenList;
 use dom::element::{AttributeHandlers, Element};
 use dom::eventtarget::{EventTarget, EventTargetTypeId};
@@ -149,8 +151,10 @@ impl<'a> PrivateHTMLLinkElementHelpers for JSRef<'a, HTMLLinkElement> {
                 let mut css_parser = CssParser::new(&mq_str);
                 let media = parse_media_query_list(&mut css_parser);
 
+                let doc = window.Document().root();
+                let pending = doc.r().prep_async_load(LoadType::Stylesheet(url.clone()));
                 let LayoutChan(ref layout_chan) = window.layout_chan();
-                layout_chan.send(Msg::LoadStylesheet(url, media)).unwrap();
+                layout_chan.send(Msg::LoadStylesheet(url, media, pending)).unwrap();
             }
             Err(e) => debug!("Parsing url {} failed: {}", href, e)
         }

components/script/layout_interface.rs

@@ -12,6 +12,7 @@ use geom::point::Point2D;
 use geom::rect::Rect;
 use libc::uintptr_t;
 use msg::constellation_msg::{PipelineExitType, WindowSizeData};
+use net_traits::PendingAsyncLoad;
 use profile_traits::mem::{Reporter, ReportsChan};
 use script_traits::{ScriptControlChan, OpaqueScriptLayoutChannel, UntrustedNodeAddress};
 use std::any::Any;
@@ -30,7 +31,7 @@ pub enum Msg {
     AddStylesheet(Stylesheet, MediaQueryList),
 
     /// Adds the given stylesheet to the document.
-    LoadStylesheet(Url, MediaQueryList),
+    LoadStylesheet(Url, MediaQueryList, PendingAsyncLoad),
 
     /// Puts a document into quirks mode, causing the quirks mode stylesheet to be loaded.
     SetQuirksMode,

components/script/script_task.rs

@@ -19,7 +19,7 @@
 
 #![allow(unsafe_code)]
 
-use document_loader::{DocumentLoader, NotifierData};
+use document_loader::{LoadType, DocumentLoader, NotifierData};
 use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::DocumentBinding::{DocumentMethods, DocumentReadyState};
 use dom::bindings::codegen::InheritTypes::{ElementCast, EventTargetCast, HTMLIFrameElementCast, NodeCast, EventCast};
@@ -731,6 +731,8 @@ impl ScriptTask {
                 self.handle_webdriver_msg(pipeline_id, msg),
             ConstellationControlMsg::TickAllAnimations(pipeline_id) =>
                 self.handle_tick_all_animations(pipeline_id),
+            ConstellationControlMsg::StylesheetLoadComplete(id, url) =>
+                self.handle_resource_loaded(id, LoadType::Stylesheet(url)),
         }
     }
 
@@ -839,6 +841,12 @@ impl ScriptTask {
     }
 
     /// Handle a request to load a page in a new child frame of an existing page.
+    fn handle_resource_loaded(&self, pipeline: PipelineId, load: LoadType) {
+        let page = get_page(&self.root_page(), pipeline);
+        let doc = page.document().root();
+        doc.r().finish_load(load);
+    }
+
     fn handle_new_layout(&self, new_layout_info: NewLayoutInfo) {
         let NewLayoutInfo {
             containing_pipeline_id,