Auto merge of #7645 - nox:omtc-types, r=Ms2ger

Introduce structs for compositing and script task constructors' arguments

Extracted from @pcwalton's #4271.

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components/compositing/compositor.rs

@@ -3,7 +3,8 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use compositor_layer::{CompositorData, CompositorLayer, WantsScrollEventsFlag};
-use compositor_task::{CompositorEventListener, CompositorProxy, CompositorReceiver, Msg};
+use compositor_task::{CompositorEventListener, CompositorProxy};
+use compositor_task::{CompositorReceiver, InitialCompositorState, Msg};
 use constellation::SendableFrameTree;
 use pipeline::CompositionPipeline;
 use scrolling::ScrollingTimerProxy;
@@ -248,23 +249,19 @@ pub fn reporter_name() -> String {
 }
 
 impl<Window: WindowMethods> IOCompositor<Window> {
-    fn new(window: Rc<Window>,
+    fn new(window: Rc<Window>, state: InitialCompositorState)
-           sender: Box<CompositorProxy + Send>,
-           receiver: Box<CompositorReceiver>,
-           constellation_chan: ConstellationChan,
-           time_profiler_chan: time::ProfilerChan,
-           mem_profiler_chan: mem::ProfilerChan)
            -> IOCompositor<Window> {
         // Register this thread as a memory reporter, via its own channel.
         let (reporter_sender, reporter_receiver) = ipc::channel().unwrap();
-        let compositor_proxy_for_memory_reporter = sender.clone_compositor_proxy();
+        let compositor_proxy_for_memory_reporter = state.sender.clone_compositor_proxy();
         ROUTER.add_route(reporter_receiver.to_opaque(), box move |reporter_request| {
             let reporter_request: ReporterRequest = reporter_request.to().unwrap();
             compositor_proxy_for_memory_reporter.send(Msg::CollectMemoryReports(
                     reporter_request.reports_channel));
         });
         let reporter = Reporter(reporter_sender);
-        mem_profiler_chan.send(mem::ProfilerMsg::RegisterReporter(reporter_name(), reporter));
+        state.mem_profiler_chan.send(
+            mem::ProfilerMsg::RegisterReporter(reporter_name(), reporter));
 
         let window_size = window.framebuffer_size();
         let hidpi_factor = window.hidpi_factor();
@@ -276,7 +273,7 @@ impl<Window: WindowMethods> IOCompositor<Window> {
         IOCompositor {
             window: window,
             native_display: native_display,
-            port: receiver,
+            port: state.receiver,
             context: None,
             root_pipeline: None,
             pipeline_details: HashMap::new(),
@@ -286,8 +283,8 @@ impl<Window: WindowMethods> IOCompositor<Window> {
             }),
             window_size: window_size,
             hidpi_factor: hidpi_factor,
-            channel_to_self: sender.clone_compositor_proxy(),
+            channel_to_self: state.sender.clone_compositor_proxy(),
-            scrolling_timer: ScrollingTimerProxy::new(sender),
+            scrolling_timer: ScrollingTimerProxy::new(state.sender),
             composition_request: CompositionRequest::NoCompositingNecessary,
             pending_scroll_events: Vec::new(),
             composite_target: composite_target,
@@ -300,9 +297,9 @@ impl<Window: WindowMethods> IOCompositor<Window> {
             zoom_time: 0f64,
             got_load_complete_message: false,
             frame_tree_id: FrameTreeId(0),
-            constellation_chan: constellation_chan,
+            constellation_chan: state.constellation_chan,
-            time_profiler_chan: time_profiler_chan,
+            time_profiler_chan: state.time_profiler_chan,
-            mem_profiler_chan: mem_profiler_chan,
+            mem_profiler_chan: state.mem_profiler_chan,
             fragment_point: None,
             last_composite_time: 0,
             has_seen_quit_event: false,
@@ -311,19 +308,9 @@ impl<Window: WindowMethods> IOCompositor<Window> {
         }
     }
 
-    pub fn create(window: Rc<Window>,
+    pub fn create(window: Rc<Window>, state: InitialCompositorState)
-                  sender: Box<CompositorProxy + Send>,
-                  receiver: Box<CompositorReceiver>,
-                  constellation_chan: ConstellationChan,
-                  time_profiler_chan: time::ProfilerChan,
-                  mem_profiler_chan: mem::ProfilerChan)
                   -> IOCompositor<Window> {
-        let mut compositor = IOCompositor::new(window,
+        let mut compositor = IOCompositor::new(window, state);
-                                               sender,
-                                               receiver,
-                                               constellation_chan,
-                                               time_profiler_chan,
-                                               mem_profiler_chan);
 
         // Set the size of the root layer.
         compositor.update_zoom_transform();

components/compositing/compositor_task.rs

@@ -260,28 +260,16 @@ pub struct CompositorTask;
 
 impl CompositorTask {
     pub fn create<Window>(window: Option<Rc<Window>>,
-                          sender: Box<CompositorProxy + Send>,
+                          state: InitialCompositorState)
-                          receiver: Box<CompositorReceiver>,
-                          constellation_chan: ConstellationChan,
-                          time_profiler_chan: time::ProfilerChan,
-                          mem_profiler_chan: mem::ProfilerChan)
                           -> Box<CompositorEventListener + 'static>
                           where Window: WindowMethods + 'static {
         match window {
             Some(window) => {
-                box compositor::IOCompositor::create(window,
+                box compositor::IOCompositor::create(window, state)
-                                                     sender,
-                                                     receiver,
-                                                     constellation_chan,
-                                                     time_profiler_chan,
-                                                     mem_profiler_chan)
                     as Box<CompositorEventListener>
             }
             None => {
-                box headless::NullCompositor::create(receiver,
+                box headless::NullCompositor::create(state)
-                                                     constellation_chan,
-                                                     time_profiler_chan,
-                                                     mem_profiler_chan)
                     as Box<CompositorEventListener>
             }
         }
@@ -296,3 +284,17 @@ pub trait CompositorEventListener {
     /// Requests that the compositor send the title for the main frame as soon as possible.
     fn title_for_main_frame(&self);
 }
+
+/// Data used to construct a compositor.
+pub struct InitialCompositorState {
+    /// A channel to the compositor.
+    pub sender: Box<CompositorProxy + Send>,
+    /// A port on which messages inbound to the compositor can be received.
+    pub receiver: Box<CompositorReceiver>,
+    /// A channel to the constellation.
+    pub constellation_chan: ConstellationChan,
+    /// A channel to the time profiler thread.
+    pub time_profiler_chan: time::ProfilerChan,
+    /// A channel to the memory profiler thread.
+    pub mem_profiler_chan: mem::ProfilerChan,
+}

components/compositing/constellation.rs

@@ -9,7 +9,7 @@
 //! navigation context, each `Pipeline` encompassing a `ScriptTask`,
 //! `LayoutTask`, and `PaintTask`.
 
-use pipeline::{Pipeline, CompositionPipeline};
+use pipeline::{Pipeline, CompositionPipeline, InitialPipelineState};
 
 use canvas::canvas_paint_task::CanvasPaintTask;
 use canvas::webgl_paint_task::WebGLPaintTask;
@@ -139,6 +139,28 @@ pub struct Constellation<LTF, STF> {
     webgl_paint_tasks: Vec<Sender<CanvasMsg>>,
 }
 
+/// State needed to construct a constellation.
+pub struct InitialConstellationState {
+    /// A channel through which messages can be sent to the compositor.
+    pub compositor_proxy: Box<CompositorProxy + Send>,
+    /// A channel to the developer tools, if applicable.
+    pub devtools_chan: Option<Sender<DevtoolsControlMsg>>,
+    /// A channel to the image cache task.
+    pub image_cache_task: ImageCacheTask,
+    /// A channel to the font cache task.
+    pub font_cache_task: FontCacheTask,
+    /// A channel to the resource task.
+    pub resource_task: ResourceTask,
+    /// A channel to the storage task.
+    pub storage_task: StorageTask,
+    /// A channel to the time profiler thread.
+    pub time_profiler_chan: time::ProfilerChan,
+    /// A channel to the memory profiler thread.
+    pub mem_profiler_chan: mem::ProfilerChan,
+    /// Whether the constellation supports the clipboard.
+    pub supports_clipboard: bool,
+}
+
 /// Stores the navigation context for a single frame in the frame tree.
 pub struct Frame {
     prev: Vec<PipelineId>,
@@ -219,28 +241,19 @@ enum ExitPipelineMode {
 }
 
 impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
-    pub fn start(compositor_proxy: Box<CompositorProxy + Send>,
+    pub fn start(state: InitialConstellationState) -> ConstellationChan {
-                 resource_task: ResourceTask,
-                 image_cache_task: ImageCacheTask,
-                 font_cache_task: FontCacheTask,
-                 time_profiler_chan: time::ProfilerChan,
-                 mem_profiler_chan: mem::ProfilerChan,
-                 devtools_chan: Option<Sender<DevtoolsControlMsg>>,
-                 storage_task: StorageTask,
-                 supports_clipboard: bool)
-                 -> ConstellationChan {
         let (constellation_port, constellation_chan) = ConstellationChan::new();
         let constellation_chan_clone = constellation_chan.clone();
         spawn_named("Constellation".to_owned(), move || {
             let mut constellation: Constellation<LTF, STF> = Constellation {
                 chan: constellation_chan_clone,
                 request_port: constellation_port,
-                compositor_proxy: compositor_proxy,
+                compositor_proxy: state.compositor_proxy,
-                devtools_chan: devtools_chan,
+                devtools_chan: state.devtools_chan,
-                resource_task: resource_task,
+                resource_task: state.resource_task,
-                image_cache_task: image_cache_task,
+                image_cache_task: state.image_cache_task,
-                font_cache_task: font_cache_task,
+                font_cache_task: state.font_cache_task,
-                storage_task: storage_task,
+                storage_task: state.storage_task,
                 pipelines: HashMap::new(),
                 frames: HashMap::new(),
                 pipeline_to_frame_map: HashMap::new(),
@@ -250,8 +263,8 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
                 root_frame_id: None,
                 next_frame_id: FrameId(0),
                 focus_pipeline_id: None,
-                time_profiler_chan: time_profiler_chan,
+                time_profiler_chan: state.time_profiler_chan,
-                mem_profiler_chan: mem_profiler_chan,
+                mem_profiler_chan: state.mem_profiler_chan,
                 window_size: WindowSizeData {
                     visible_viewport: opts::get().initial_window_size.as_f32() *
                                           ScaleFactor::new(1.0),
@@ -260,7 +273,7 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
                     device_pixel_ratio: ScaleFactor::new(1.0),
                 },
                 phantom: PhantomData,
-                clipboard_ctx: if supports_clipboard {
+                clipboard_ctx: if state.supports_clipboard {
                     ClipboardContext::new().ok()
                 } else {
                     None
@@ -296,21 +309,23 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
 
         let spawning_paint_only = script_channel.is_some();
         let (pipeline, mut pipeline_content) =
-            Pipeline::create::<LTF, STF>(pipeline_id,
+            Pipeline::create::<LTF, STF>(InitialPipelineState {
-                                         parent_info,
+                id: pipeline_id,
-                                         self.chan.clone(),
+                parent_info: parent_info,
-                                         self.compositor_proxy.clone_compositor_proxy(),
+                constellation_chan: self.chan.clone(),
-                                         self.devtools_chan.clone(),
+                compositor_proxy: self.compositor_proxy.clone_compositor_proxy(),
-                                         self.image_cache_task.clone(),
+                devtools_chan: self.devtools_chan.clone(),
-                                         self.font_cache_task.clone(),
+                image_cache_task: self.image_cache_task.clone(),
-                                         self.resource_task.clone(),
+                font_cache_task: self.font_cache_task.clone(),
-                                         self.storage_task.clone(),
+                resource_task: self.resource_task.clone(),
-                                         self.time_profiler_chan.clone(),
+                storage_task: self.storage_task.clone(),
-                                         self.mem_profiler_chan.clone(),
+                time_profiler_chan: self.time_profiler_chan.clone(),
-                                         initial_window_rect,
+                mem_profiler_chan: self.mem_profiler_chan.clone(),
-                                         script_channel,
+                window_rect: initial_window_rect,
-                                         load_data,
+                script_chan: script_channel,
-                                         self.window_size.device_pixel_ratio);
+                load_data: load_data,
+                device_pixel_ratio: self.window_size.device_pixel_ratio,
+            });
 
         // TODO(pcwalton): In multiprocess mode, send that `PipelineContent` instance over to
         // the content process and call this over there.

components/compositing/headless.rs

@@ -2,7 +2,8 @@
  * 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 compositor_task::{CompositorEventListener, CompositorReceiver, Msg};
+use compositor_task::{CompositorEventListener, CompositorReceiver};
+use compositor_task::{InitialCompositorState, Msg};
 use windowing::WindowEvent;
 
 use euclid::scale_factor::ScaleFactor;
@@ -29,28 +30,17 @@ pub struct NullCompositor {
 }
 
 impl NullCompositor {
-    fn new(port: Box<CompositorReceiver>,
+    fn new(state: InitialCompositorState) -> NullCompositor {
-           constellation_chan: ConstellationChan,
-           time_profiler_chan: time::ProfilerChan,
-           mem_profiler_chan: mem::ProfilerChan)
-           -> NullCompositor {
         NullCompositor {
-            port: port,
+            port: state.receiver,
-            constellation_chan: constellation_chan,
+            constellation_chan: state.constellation_chan,
-            time_profiler_chan: time_profiler_chan,
+            time_profiler_chan: state.time_profiler_chan,
-            mem_profiler_chan: mem_profiler_chan,
+            mem_profiler_chan: state.mem_profiler_chan,
         }
     }
 
-    pub fn create(port: Box<CompositorReceiver>,
+    pub fn create(state: InitialCompositorState) -> NullCompositor {
-                  constellation_chan: ConstellationChan,
+        let compositor = NullCompositor::new(state);
-                  time_profiler_chan: time::ProfilerChan,
-                  mem_profiler_chan: mem::ProfilerChan)
-                  -> NullCompositor {
-        let compositor = NullCompositor::new(port,
-                                             constellation_chan,
-                                             time_profiler_chan,
-                                             mem_profiler_chan);
 
         // Tell the constellation about the initial fake size.
         {

components/compositing/pipeline.rs

@@ -4,8 +4,8 @@
 
 use CompositorProxy;
 use layout_traits::{LayoutTaskFactory, LayoutControlChan};
-use script_traits::{LayoutControlMsg, ScriptTaskFactory};
+use script_traits::{ConstellationControlMsg, InitialScriptState};
-use script_traits::{NewLayoutInfo, ConstellationControlMsg};
+use script_traits::{LayoutControlMsg, NewLayoutInfo, ScriptTaskFactory};
 
 use compositor_task;
 use devtools_traits::{DevtoolsControlMsg, ScriptToDevtoolsControlMsg};
@@ -63,25 +63,46 @@ pub struct CompositionPipeline {
     pub chrome_to_paint_chan: Sender<ChromeToPaintMsg>,
 }
 
+/// Initial setup data needed to construct a pipeline.
+pub struct InitialPipelineState {
+    /// The ID of the pipeline to create.
+    pub id: PipelineId,
+    /// The subpage ID of this pipeline to create in its pipeline parent.
+    /// If `None`, this is the root.
+    pub parent_info: Option<(PipelineId, SubpageId)>,
+    /// A channel to the associated constellation.
+    pub constellation_chan: ConstellationChan,
+    /// A channel to the compositor.
+    pub compositor_proxy: Box<CompositorProxy + 'static + Send>,
+    /// A channel to the developer tools, if applicable.
+    pub devtools_chan: Option<Sender<DevtoolsControlMsg>>,
+    /// A channel to the image cache task.
+    pub image_cache_task: ImageCacheTask,
+    /// A channel to the font cache task.
+    pub font_cache_task: FontCacheTask,
+    /// A channel to the resource task.
+    pub resource_task: ResourceTask,
+    /// A channel to the storage task.
+    pub storage_task: StorageTask,
+    /// A channel to the time profiler thread.
+    pub time_profiler_chan: time::ProfilerChan,
+    /// A channel to the memory profiler thread.
+    pub mem_profiler_chan: profile_mem::ProfilerChan,
+    /// Information about the initial window size.
+    pub window_rect: Option<TypedRect<PagePx, f32>>,
+    /// Information about the device pixel ratio.
+    pub device_pixel_ratio: ScaleFactor<ViewportPx, DevicePixel, f32>,
+    /// A channel to the script thread, if applicable. If this is `Some`,
+    /// then `parent_info` must also be `Some`.
+    pub script_chan: Option<Sender<ConstellationControlMsg>>,
+    /// Information about the page to load.
+    pub load_data: LoadData,
+}
+
 impl Pipeline {
     /// Starts a paint task, layout task, and possibly a script task.
     /// Returns the channels wrapped in a struct.
-    /// If script_pipeline is not None, then subpage_id must also be not None.
+    pub fn create<LTF, STF>(state: InitialPipelineState)
-    pub fn create<LTF, STF>(id: PipelineId,
-                            parent_info: Option<(PipelineId, SubpageId)>,
-                            constellation_chan: ConstellationChan,
-                            compositor_proxy: Box<CompositorProxy + 'static + Send>,
-                            devtools_chan: Option<Sender<DevtoolsControlMsg>>,
-                            image_cache_task: ImageCacheTask,
-                            font_cache_task: FontCacheTask,
-                            resource_task: ResourceTask,
-                            storage_task: StorageTask,
-                            time_profiler_chan: time::ProfilerChan,
-                            mem_profiler_chan: profile_mem::ProfilerChan,
-                            window_rect: Option<TypedRect<PagePx, f32>>,
-                            script_chan: Option<Sender<ConstellationControlMsg>>,
-                            load_data: LoadData,
-                            device_pixel_ratio: ScaleFactor<ViewportPx, DevicePixel, f32>)
                             -> (Pipeline, PipelineContent)
                             where LTF: LayoutTaskFactory, STF: ScriptTaskFactory {
         let (layout_to_paint_chan, layout_to_paint_port) = util::ipc::optional_ipc_channel();
@@ -92,20 +113,20 @@ impl Pipeline {
         let mut pipeline_port = Some(pipeline_port);
 
         let failure = Failure {
-            pipeline_id: id,
+            pipeline_id: state.id,
-            parent_info: parent_info,
+            parent_info: state.parent_info,
         };
 
-        let window_size = window_rect.map(|rect| {
+        let window_size = state.window_rect.map(|rect| {
             WindowSizeData {
                 visible_viewport: rect.size,
                 initial_viewport: rect.size * ScaleFactor::new(1.0),
-                device_pixel_ratio: device_pixel_ratio,
+                device_pixel_ratio: state.device_pixel_ratio,
             }
         });
 
         // Route messages coming from content to devtools as appropriate.
-        let script_to_devtools_chan = devtools_chan.as_ref().map(|devtools_chan| {
+        let script_to_devtools_chan = state.devtools_chan.as_ref().map(|devtools_chan| {
             let (script_to_devtools_chan, script_to_devtools_port) = ipc::channel().unwrap();
             let devtools_chan = (*devtools_chan).clone();
             ROUTER.add_route(script_to_devtools_port.to_opaque(), box move |message| {
@@ -115,15 +136,15 @@ impl Pipeline {
             script_to_devtools_chan
         });
 
-        let (script_chan, script_port) = match script_chan {
+        let (script_chan, script_port) = match state.script_chan {
             Some(script_chan) => {
                 let (containing_pipeline_id, subpage_id) =
-                    parent_info.expect("script_pipeline != None but subpage_id == None");
+                    state.parent_info.expect("script_pipeline != None but subpage_id == None");
                 let new_layout_info = NewLayoutInfo {
                     containing_pipeline_id: containing_pipeline_id,
-                    new_pipeline_id: id,
+                    new_pipeline_id: state.id,
                     subpage_id: subpage_id,
-                    load_data: load_data.clone(),
+                    load_data: state.load_data.clone(),
                     paint_chan: box layout_to_paint_chan.clone() as Box<Any + Send>,
                     failure: failure,
                     pipeline_port: mem::replace(&mut pipeline_port, None).unwrap(),
@@ -140,31 +161,31 @@ impl Pipeline {
             }
         };
 
-        let pipeline = Pipeline::new(id,
+        let pipeline = Pipeline::new(state.id,
-                                     parent_info,
+                                     state.parent_info,
                                      script_chan.clone(),
                                      LayoutControlChan(pipeline_chan),
                                      chrome_to_paint_chan.clone(),
                                      layout_shutdown_port,
                                      paint_shutdown_port,
-                                     load_data.url.clone(),
+                                     state.load_data.url.clone(),
-                                     window_rect);
+                                     state.window_rect);
 
         let pipeline_content = PipelineContent {
-            id: id,
+            id: state.id,
-            parent_info: parent_info,
+            parent_info: state.parent_info,
-            constellation_chan: constellation_chan,
+            constellation_chan: state.constellation_chan,
-            compositor_proxy: compositor_proxy,
+            compositor_proxy: state.compositor_proxy,
             devtools_chan: script_to_devtools_chan,
-            image_cache_task: image_cache_task,
+            image_cache_task: state.image_cache_task,
-            font_cache_task: font_cache_task,
+            font_cache_task: state.font_cache_task,
-            resource_task: resource_task,
+            resource_task: state.resource_task,
-            storage_task: storage_task,
+            storage_task: state.storage_task,
-            time_profiler_chan: time_profiler_chan,
+            time_profiler_chan: state.time_profiler_chan,
-            mem_profiler_chan: mem_profiler_chan,
+            mem_profiler_chan: state.mem_profiler_chan,
             window_size: window_size,
             script_chan: script_chan,
-            load_data: load_data,
+            load_data: state.load_data,
             failure: failure,
             script_port: script_port,
             layout_to_paint_chan: layout_to_paint_chan,
@@ -319,23 +340,22 @@ impl PipelineContent {
                 script_to_compositor_port)
         });
 
-        ScriptTaskFactory::create(None::<&mut STF>,
+        ScriptTaskFactory::create(None::<&mut STF>, InitialScriptState {
-                                  self.id,
+            id: self.id,
-                                  self.parent_info,
+            parent_info: self.parent_info,
-                                  script_to_compositor_chan,
+            compositor: script_to_compositor_chan,
-                                  &layout_pair,
+            control_chan: self.script_chan.clone(),
-                                  self.script_chan.clone(),
+            control_port: mem::replace(&mut self.script_port, None).unwrap(),
-                                  mem::replace(&mut self.script_port, None).unwrap(),
+            constellation_chan: self.constellation_chan.clone(),
-                                  self.constellation_chan.clone(),
+            failure_info: self.failure.clone(),
-                                  self.failure.clone(),
+            resource_task: self.resource_task,
-                                  self.resource_task,
+            storage_task: self.storage_task.clone(),
-                                  self.storage_task.clone(),
+            image_cache_task: self.image_cache_task.clone(),
-                                  self.image_cache_task.clone(),
+            time_profiler_chan: self.time_profiler_chan.clone(),
-                                  self.time_profiler_chan.clone(),
+            mem_profiler_chan: self.mem_profiler_chan.clone(),
-                                  self.mem_profiler_chan.clone(),
+            devtools_chan: self.devtools_chan,
-                                  self.devtools_chan,
+            window_size: self.window_size,
-                                  self.window_size,
+        }, &layout_pair, self.load_data.clone());
-                                  self.load_data.clone());
 
         LayoutTaskFactory::create(None::<&mut LTF>,
                                   self.id,

components/script/script_task.rs

@@ -54,9 +54,9 @@ use devtools_traits::ScriptToDevtoolsControlMsg;
 use devtools_traits::{DevtoolsPageInfo, DevtoolScriptControlMsg};
 use msg::compositor_msg::{LayerId, ScriptToCompositorMsg};
 use msg::constellation_msg::Msg as ConstellationMsg;
-use msg::constellation_msg::{ConstellationChan, FocusType};
+use msg::constellation_msg::{ConstellationChan, FocusType, LoadData};
-use msg::constellation_msg::{Failure, WindowSizeData, PipelineExitType};
+use msg::constellation_msg::{MozBrowserEvent, PipelineExitType, PipelineId};
-use msg::constellation_msg::{LoadData, PipelineId, SubpageId, MozBrowserEvent, WorkerId};
+use msg::constellation_msg::{SubpageId, WindowSizeData, WorkerId};
 use msg::webdriver_msg::WebDriverScriptCommand;
 use net_traits::LoadData as NetLoadData;
 use net_traits::image_cache_task::{ImageCacheChan, ImageCacheTask, ImageCacheResult};
@@ -67,10 +67,9 @@ use profile_traits::time::{self, ProfilerCategory, profile};
 use script_traits::CompositorEvent::{MouseDownEvent, MouseUpEvent};
 use script_traits::CompositorEvent::{MouseMoveEvent, KeyEvent};
 use script_traits::CompositorEvent::{ResizeEvent, ClickEvent};
-use script_traits::ConstellationControlMsg;
+use script_traits::{CompositorEvent, ConstellationControlMsg};
-use script_traits::{CompositorEvent, MouseButton};
+use script_traits::{InitialScriptState, MouseButton, NewLayoutInfo};
-use script_traits::{NewLayoutInfo, OpaqueScriptLayoutChannel};
+use script_traits::{OpaqueScriptLayoutChannel, ScriptState, ScriptTaskFactory};
-use script_traits::{ScriptState, ScriptTaskFactory};
 use string_cache::Atom;
 use util::opts;
 use util::str::DOMString;
@@ -466,42 +465,25 @@ impl ScriptTaskFactory for ScriptTask {
     }
 
     fn create(_phantom: Option<&mut ScriptTask>,
-              id: PipelineId,
+              state: InitialScriptState,
-              parent_info: Option<(PipelineId, SubpageId)>,
-              compositor: IpcSender<ScriptToCompositorMsg>,
               layout_chan: &OpaqueScriptLayoutChannel,
-              control_chan: Sender<ConstellationControlMsg>,
-              control_port: Receiver<ConstellationControlMsg>,
-              constellation_chan: ConstellationChan,
-              failure_msg: Failure,
-              resource_task: ResourceTask,
-              storage_task: StorageTask,
-              image_cache_task: ImageCacheTask,
-              time_profiler_chan: time::ProfilerChan,
-              mem_profiler_chan: mem::ProfilerChan,
-              devtools_chan: Option<IpcSender<ScriptToDevtoolsControlMsg>>,
-              window_size: Option<WindowSizeData>,
               load_data: LoadData) {
-        let ConstellationChan(const_chan) = constellation_chan.clone();
+        let ConstellationChan(const_chan) = state.constellation_chan.clone();
         let (script_chan, script_port) = channel();
         let layout_chan = LayoutChan(layout_chan.sender());
-        spawn_named_with_send_on_failure(format!("ScriptTask {:?}", id), task_state::SCRIPT, move || {
+        let failure_info = state.failure_info;
+        spawn_named_with_send_on_failure(format!("ScriptTask {:?}", state.id), task_state::SCRIPT, move || {
             let roots = RootCollection::new();
             let _stack_roots_tls = StackRootTLS::new(&roots);
             let chan = MainThreadScriptChan(script_chan);
             let channel_for_reporter = chan.clone();
-            let script_task = ScriptTask::new(compositor,
+            let id = state.id;
+            let parent_info = state.parent_info;
+            let mem_profiler_chan = state.mem_profiler_chan.clone();
+            let window_size = state.window_size;
+            let script_task = ScriptTask::new(state,
                                               script_port,
-                                              chan,
+                                              chan);
-                                              control_chan,
-                                              control_port,
-                                              constellation_chan,
-                                              Arc::new(resource_task),
-                                              storage_task,
-                                              image_cache_task,
-                                              time_profiler_chan.clone(),
-                                              mem_profiler_chan.clone(),
-                                              devtools_chan);
 
             SCRIPT_TASK_ROOT.with(|root| {
                 *root.borrow_mut() = Some(&script_task as *const _);
@@ -520,7 +502,7 @@ impl ScriptTaskFactory for ScriptTask {
 
             // This must always be the very last operation performed before the task completes
             failsafe.neuter();
-        }, ConstellationMsg::Failure(failure_msg), const_chan);
+        }, ConstellationMsg::Failure(failure_info), const_chan);
     }
 }
 
@@ -606,18 +588,9 @@ impl ScriptTask {
     }
 
     /// Creates a new script task.
-    pub fn new(compositor: IpcSender<ScriptToCompositorMsg>,
+    pub fn new(state: InitialScriptState,
                port: Receiver<MainThreadScriptMsg>,
-               chan: MainThreadScriptChan,
+               chan: MainThreadScriptChan)
-               control_chan: Sender<ConstellationControlMsg>,
-               control_port: Receiver<ConstellationControlMsg>,
-               constellation_chan: ConstellationChan,
-               resource_task: Arc<ResourceTask>,
-               storage_task: StorageTask,
-               image_cache_task: ImageCacheTask,
-               time_profiler_chan: time::ProfilerChan,
-               mem_profiler_chan: mem::ProfilerChan,
-               devtools_chan: Option<IpcSender<ScriptToDevtoolsControlMsg>>)
                -> ScriptTask {
         let runtime = ScriptTask::new_rt_and_cx();
 
@@ -639,23 +612,23 @@ impl ScriptTask {
             page: DOMRefCell::new(None),
             incomplete_loads: DOMRefCell::new(vec!()),
 
-            image_cache_task: image_cache_task,
+            image_cache_task: state.image_cache_task,
             image_cache_channel: ImageCacheChan(ipc_image_cache_channel),
             image_cache_port: image_cache_port,
 
-            resource_task: resource_task,
+            resource_task: Arc::new(state.resource_task),
-            storage_task: storage_task,
+            storage_task: state.storage_task,
 
             port: port,
             chan: chan,
-            control_chan: control_chan,
+            control_chan: state.control_chan,
-            control_port: control_port,
+            control_port: state.control_port,
-            constellation_chan: constellation_chan,
+            constellation_chan: state.constellation_chan,
-            compositor: DOMRefCell::new(compositor),
+            compositor: DOMRefCell::new(state.compositor),
-            time_profiler_chan: time_profiler_chan,
+            time_profiler_chan: state.time_profiler_chan,
-            mem_profiler_chan: mem_profiler_chan,
+            mem_profiler_chan: state.mem_profiler_chan,
 
-            devtools_chan: devtools_chan,
+            devtools_chan: state.devtools_chan,
             devtools_port: devtools_port,
             devtools_sender: ipc_devtools_sender,
 

components/script_traits/lib.rs

@@ -171,26 +171,46 @@ pub enum CompositorEvent {
 /// crates that don't need to know about them.
 pub struct OpaqueScriptLayoutChannel(pub (Box<Any + Send>, Box<Any + Send>));
 
+/// Data needed to construct a script thread.
+pub struct InitialScriptState {
+    /// The ID of the pipeline with which this script thread is associated.
+    pub id: PipelineId,
+    /// The subpage ID of this pipeline to create in its pipeline parent.
+    /// If `None`, this is the root.
+    pub parent_info: Option<(PipelineId, SubpageId)>,
+    /// The compositor.
+    pub compositor: IpcSender<ScriptToCompositorMsg>,
+    /// A channel with which messages can be sent to us (the script task).
+    pub control_chan: Sender<ConstellationControlMsg>,
+    /// A port on which messages sent by the constellation to script can be received.
+    pub control_port: Receiver<ConstellationControlMsg>,
+    /// A channel on which messages can be sent to the constellation from script.
+    pub constellation_chan: ConstellationChan,
+    /// Information that script sends out when it panics.
+    pub failure_info: Failure,
+    /// A channel to the resource manager task.
+    pub resource_task: ResourceTask,
+    /// A channel to the storage task.
+    pub storage_task: StorageTask,
+    /// A channel to the image cache task.
+    pub image_cache_task: ImageCacheTask,
+    /// A channel to the time profiler thread.
+    pub time_profiler_chan: time::ProfilerChan,
+    /// A channel to the memory profiler thread.
+    pub mem_profiler_chan: mem::ProfilerChan,
+    /// A channel to the developer tools, if applicable.
+    pub devtools_chan: Option<IpcSender<ScriptToDevtoolsControlMsg>>,
+    /// Information about the initial window size.
+    pub window_size: Option<WindowSizeData>,
+}
+
 /// This trait allows creating a `ScriptTask` without depending on the `script`
 /// crate.
 pub trait ScriptTaskFactory {
     /// Create a `ScriptTask`.
     fn create(_phantom: Option<&mut Self>,
-              id: PipelineId,
+              state: InitialScriptState,
-              parent_info: Option<(PipelineId, SubpageId)>,
-              compositor: IpcSender<ScriptToCompositorMsg>,
               layout_chan: &OpaqueScriptLayoutChannel,
-              control_chan: Sender<ConstellationControlMsg>,
-              control_port: Receiver<ConstellationControlMsg>,
-              constellation_msg: ConstellationChan,
-              failure_msg: Failure,
-              resource_task: ResourceTask,
-              storage_task: StorageTask,
-              image_cache_task: ImageCacheTask,
-              time_profiler_chan: time::ProfilerChan,
-              mem_profiler_chan: mem::ProfilerChan,
-              devtools_chan: Option<IpcSender<ScriptToDevtoolsControlMsg>>,
-              window_size: Option<WindowSizeData>,
               load_data: LoadData);
     /// Create a script -> layout channel (`Sender`, `Receiver` pair).
     fn create_layout_channel(_phantom: Option<&mut Self>) -> OpaqueScriptLayoutChannel;

components/servo/lib.rs

@@ -81,6 +81,8 @@ pub use export::gleam::gl;
 use compositing::CompositorEventListener;
 use compositing::windowing::WindowEvent;
 
+use compositing::compositor_task::InitialCompositorState;
+use compositing::constellation::InitialConstellationState;
 use compositing::windowing::WindowMethods;
 use compositing::{CompositorProxy, CompositorTask, Constellation};
 
@@ -163,12 +165,13 @@ impl Browser {
 
         // The compositor coordinates with the client window to create the final
         // rendered page and display it somewhere.
-        let compositor = CompositorTask::create(window,
+        let compositor = CompositorTask::create(window, InitialCompositorState {
-                                                compositor_proxy,
+            sender: compositor_proxy,
-                                                compositor_receiver,
+            receiver: compositor_receiver,
-                                                constellation_chan,
+            constellation_chan: constellation_chan,
-                                                time_profiler_chan,
+            time_profiler_chan: time_profiler_chan,
-                                                mem_profiler_chan);
+            mem_profiler_chan: mem_profiler_chan,
+        });
 
         Browser {
             compositor: compositor,
@@ -208,17 +211,20 @@ fn create_constellation(opts: opts::Opts,
     let font_cache_task = FontCacheTask::new(resource_task.clone());
     let storage_task: StorageTask = StorageTaskFactory::new();
 
-    let constellation_chan = Constellation::<layout::layout_task::LayoutTask,
+    let initial_state = InitialConstellationState {
-    script::script_task::ScriptTask>::start(
+        compositor_proxy: compositor_proxy,
-        compositor_proxy,
+        devtools_chan: devtools_chan,
-        resource_task,
+        image_cache_task: image_cache_task,
-        image_cache_task,
+        font_cache_task: font_cache_task,
-        font_cache_task,
+        resource_task: resource_task,
-        time_profiler_chan,
+        storage_task: storage_task,
-        mem_profiler_chan,
+        time_profiler_chan: time_profiler_chan,
-        devtools_chan,
+        mem_profiler_chan: mem_profiler_chan,
-        storage_task,
+        supports_clipboard: supports_clipboard,
-        supports_clipboard);
+    };
+    let constellation_chan =
+        Constellation::<layout::layout_task::LayoutTask,
+                        script::script_task::ScriptTask>::start(initial_state);
 
     // Send the URL command to the constellation.
     match opts.url {