Auto merge of #9603 - Ms2ger:document-bc, r=jdm

Store a pointer to the browsing context in the Document.

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components/script/dom/browsingcontext.rs

@@ -2,6 +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::cell::DOMRefCell;
 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};
@@ -25,26 +26,24 @@ use js::jsval::{ObjectValue, UndefinedValue, PrivateValue};
 #[dom_struct]
 pub struct BrowsingContext {
     reflector: Reflector,
-    history: Vec<SessionHistoryEntry>,
+    history: DOMRefCell<Vec<SessionHistoryEntry>>,
     active_index: usize,
     frame_element: Option<JS<Element>>,
 }
 
 impl BrowsingContext {
-    pub fn new_inherited(document: &Document, frame_element: Option<&Element>) -> BrowsingContext {
+    pub fn new_inherited(frame_element: Option<&Element>) -> BrowsingContext {
         BrowsingContext {
             reflector: Reflector::new(),
-            history: vec![SessionHistoryEntry::new(document)],
+            history: DOMRefCell::new(vec![]),
             active_index: 0,
             frame_element: frame_element.map(JS::from_ref),
         }
     }
 
     #[allow(unsafe_code)]
-    pub fn new(document: &Document, frame_element: Option<&Element>) -> Root<BrowsingContext> {
+    pub fn new(window: &Window, frame_element: Option<&Element>) -> Root<BrowsingContext> {
         unsafe {
-            let window = document.window();
-
             let WindowProxyHandler(handler) = window.windowproxy_handler();
             assert!(!handler.is_null());
 
@@ -58,7 +57,7 @@ impl BrowsingContext {
                 NewWindowProxy(cx, parent, handler));
             assert!(!window_proxy.ptr.is_null());
 
-            let object = box BrowsingContext::new_inherited(document, frame_element);
+            let object = box BrowsingContext::new_inherited(frame_element);
 
             let raw = Box::into_raw(object);
             SetProxyExtra(window_proxy.ptr, 0, PrivateValue(raw as *const _));
@@ -69,12 +68,18 @@ impl BrowsingContext {
         }
     }
 
-    pub fn active_document(&self) -> &Document {
+    pub fn init(&self, document: &Document) {
-        &*self.history[self.active_index].document
+        assert!(self.history.borrow().is_empty());
+        assert_eq!(self.active_index, 0);
+        self.history.borrow_mut().push(SessionHistoryEntry::new(document));
     }
 
-    pub fn active_window(&self) -> &Window {
+    pub fn active_document(&self) -> Root<Document> {
-        self.active_document().window()
+        Root::from_ref(&*self.history.borrow()[self.active_index].document)
+    }
+
+    pub fn active_window(&self) -> Root<Window> {
+        Root::from_ref(self.active_document().window())
     }
 
     pub fn frame_element(&self) -> Option<&Element> {

components/script/dom/document.rs

@@ -30,6 +30,7 @@ use dom::bindings::reflector::{Reflectable, reflect_dom_object};
 use dom::bindings::trace::RootedVec;
 use dom::bindings::xmlname::XMLName::InvalidXMLName;
 use dom::bindings::xmlname::{validate_and_extract, namespace_from_domstring, xml_name_type};
+use dom::browsingcontext::BrowsingContext;
 use dom::comment::Comment;
 use dom::customevent::CustomEvent;
 use dom::documentfragment::DocumentFragment;
@@ -129,6 +130,8 @@ enum ParserBlockedByScript {
 pub struct Document {
     node: Node,
     window: JS<Window>,
+    /// https://html.spec.whatwg.org/multipage/#concept-document-bc
+    browsing_context: Option<JS<BrowsingContext>>,
     implementation: MutNullableHeap<JS<DOMImplementation>>,
     location: MutNullableHeap<JS<Location>>,
     content_type: DOMString,
@@ -279,6 +282,12 @@ impl Document {
         self.loader.borrow_mut()
     }
 
+    /// https://html.spec.whatwg.org/multipage/#concept-document-bc
+    #[inline]
+    pub fn browsing_context(&self) -> Option<&BrowsingContext> {
+        self.browsing_context.as_ref().map(|browsing_context| &**browsing_context)
+    }
+
     #[inline]
     pub fn window(&self) -> &Window {
         &*self.window
@@ -309,7 +318,7 @@ impl Document {
         let browsing_context = browsing_context.as_ref().unwrap();
         let active_document = browsing_context.active_document();
 
-        if self != active_document {
+        if self != &*active_document {
             return false;
         }
         // FIXME: It should also check whether the browser context is top-level or not
@@ -1507,6 +1516,7 @@ impl LayoutDocumentHelpers for LayoutJS<Document> {
 
 impl Document {
     pub fn new_inherited(window: &Window,
+                         browsing_context: Option<&BrowsingContext>,
                          url: Option<Url>,
                          is_html_document: IsHTMLDocument,
                          content_type: Option<DOMString>,
@@ -1525,6 +1535,7 @@ impl Document {
         Document {
             node: Node::new_document_node(),
             window: JS::from_ref(window),
+            browsing_context: browsing_context.map(JS::from_ref),
             implementation: Default::default(),
             location: Default::default(),
             content_type: match content_type {
@@ -1593,6 +1604,7 @@ impl Document {
         let doc = doc.r();
         let docloader = DocumentLoader::new(&*doc.loader());
         Ok(Document::new(win,
+                         None,
                          None,
                          IsHTMLDocument::NonHTMLDocument,
                          None,
@@ -1602,6 +1614,7 @@ impl Document {
     }
 
     pub fn new(window: &Window,
+               browsing_context: Option<&BrowsingContext>,
                url: Option<Url>,
                doctype: IsHTMLDocument,
                content_type: Option<DOMString>,
@@ -1610,6 +1623,7 @@ impl Document {
                doc_loader: DocumentLoader)
                -> Root<Document> {
         let document = reflect_dom_object(box Document::new_inherited(window,
+                                                                      browsing_context,
                                                                       url,
                                                                       doctype,
                                                                       content_type,
@@ -1672,6 +1686,7 @@ impl Document {
                 IsHTMLDocument::NonHTMLDocument
             };
             let new_doc = Document::new(self.window(),
+                                        None,
                                         None,
                                         doctype,
                                         None,
@@ -1761,7 +1776,7 @@ impl DocumentMethods for Document {
                 // Step 2.
                 let candidate = browsing_context.active_document();
                 // Step 3.
-                if candidate == target {
+                if &*candidate == target {
                     true
                 } else {
                     false //TODO  Step 4.

components/script/dom/domimplementation.rs

@@ -115,6 +115,7 @@ impl DOMImplementationMethods for DOMImplementation {
 
         // Step 1-2.
         let doc = Document::new(win,
+                                None,
                                 None,
                                 IsHTMLDocument::HTMLDocument,
                                 None,

components/script/dom/domparser.rs

@@ -59,6 +59,7 @@ impl DOMParserMethods for DOMParser {
         match ty {
             Text_html => {
                 let document = Document::new(&self.window,
+                                             None,
                                              Some(url.clone()),
                                              IsHTMLDocument::HTMLDocument,
                                              Some(content_type),
@@ -72,6 +73,7 @@ impl DOMParserMethods for DOMParser {
             Text_xml => {
                 // FIXME: this should probably be FromParser when we actually parse the string (#3756).
                 let document = Document::new(&self.window,
+                                             None,
                                              Some(url.clone()),
                                              IsHTMLDocument::NonHTMLDocument,
                                              Some(content_type),

components/script/dom/node.rs

@@ -1605,7 +1605,8 @@ impl Node {
                 };
                 let window = document.window();
                 let loader = DocumentLoader::new(&*document.loader());
-                let document = Document::new(window, Some((*document.url()).clone()),
+                let document = Document::new(window, None,
+                                             Some((*document.url()).clone()),
                                              is_html_doc, None,
                                              None, DocumentSource::NotFromParser, loader);
                 Root::upcast::<Node>(document)

components/script/dom/window.rs

@@ -426,7 +426,7 @@ impl WindowMethods for Window {
 
     // https://html.spec.whatwg.org/multipage/#dom-document-2
     fn Document(&self) -> Root<Document> {
-        Root::from_ref(self.browsing_context().as_ref().unwrap().active_document())
+        self.browsing_context().as_ref().unwrap().active_document()
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-location
@@ -1095,8 +1095,9 @@ impl Window {
         (element, response.rect)
     }
 
-    pub fn init_browsing_context(&self, doc: &Document, frame_element: Option<&Element>) {
+    pub fn init_browsing_context(&self, browsing_context: &BrowsingContext) {
-        self.browsing_context.set(Some(&BrowsingContext::new(doc, frame_element)));
+        assert!(self.browsing_context.get().is_none());
+        self.browsing_context.set(Some(&browsing_context));
     }
 
     /// Commence a new URL load which will either replace this window or scroll to a fragment.
@@ -1283,7 +1284,7 @@ impl Window {
         browsing_context.frame_element().map(|frame_element| {
             let window = window_from_node(frame_element);
             let context = window.browsing_context();
-            Root::from_ref(context.unwrap().active_window())
+            context.unwrap().active_window()
         })
     }
 }

components/script/dom/xmldocument.rs

@@ -35,6 +35,7 @@ impl XMLDocument {
                      doc_loader: DocumentLoader) -> XMLDocument {
         XMLDocument {
             document: Document::new_inherited(window,
+                                              None,
                                               url,
                                               is_html_document,
                                               content_type,

components/script/dom/xmlhttprequest.rs

@@ -1230,6 +1230,7 @@ impl XMLHttpRequest {
             DOMString::from(format!("{}", mime))
         });
         Document::new(win,
+                      None,
                       parsed_url,
                       is_html_document,
                       content_type,

components/script/parse/html.rs

@@ -275,7 +275,7 @@ pub fn parse_html_fragment(context_node: &Node,
 
     // Step 1.
     let loader = DocumentLoader::new(&*context_document.loader());
-    let document = Document::new(window.r(), Some(url.clone()),
+    let document = Document::new(window.r(), None, Some(url.clone()),
                                  IsHTMLDocument::HTMLDocument,
                                  None, None,
                                  DocumentSource::FromParser,

components/script/script_thread.rs

@@ -32,6 +32,7 @@ use dom::bindings::js::{RootCollectionPtr, RootedReference};
 use dom::bindings::refcounted::{LiveDOMReferences, Trusted, TrustedReference, trace_refcounted_objects};
 use dom::bindings::trace::{JSTraceable, RootedVec, trace_traceables};
 use dom::bindings::utils::{DOM_CALLBACKS, WRAP_CALLBACKS};
+use dom::browsingcontext::BrowsingContext;
 use dom::document::{Document, DocumentProgressHandler, DocumentSource, FocusType, IsHTMLDocument};
 use dom::element::Element;
 use dom::event::{Event, EventBubbles, EventCancelable};
@@ -1795,6 +1796,10 @@ impl ScriptThread {
                                  incomplete.parent_info,
                                  incomplete.window_size);
 
+        let frame_element = frame_element.r().map(Castable::upcast);
+        let browsing_context = BrowsingContext::new(&window, frame_element);
+        window.init_browsing_context(&browsing_context);
+
         let last_modified = metadata.headers.as_ref().and_then(|headers| {
             headers.get().map(|&LastModified(HttpDate(ref tm))| dom_last_modified(tm))
         });
@@ -1822,16 +1827,14 @@ impl ScriptThread {
         };
 
         let document = Document::new(window.r(),
+                                     Some(&browsing_context),
                                      Some(final_url.clone()),
                                      is_html_document,
                                      content_type,
                                      last_modified,
                                      DocumentSource::FromParser,
                                      loader);
-
+        browsing_context.init(&document);
-        let frame_element = frame_element.r().map(Castable::upcast);
-        window.init_browsing_context(document.r(), frame_element);
-
         document.set_ready_state(DocumentReadyState::Loading);
 
         // Create the root frame