servo: Merge #7046 - Implement a base_url getter and use it for style…

… attributes (from Ms2ger:base-url); r=dzbarsky

Source-Repo: https://github.com/servo/servo
Source-Revision: 530d4547c945fbf120d546d6e9a31b8f3bacc78f

servo/components/script/dom/document.rs

@@ -23,6 +23,7 @@ use dom::bindings::codegen::InheritTypes::{HTMLAreaElementDerived, HTMLEmbedElem
 use dom::bindings::codegen::InheritTypes::{HTMLFormElementDerived, HTMLImageElementDerived};
 use dom::bindings::codegen::InheritTypes::{HTMLScriptElementDerived, HTMLTitleElementDerived};
 use dom::bindings::codegen::InheritTypes::ElementDerived;
+use dom::bindings::codegen::InheritTypes::HTMLBaseElementCast;
 use dom::bindings::codegen::UnionTypes::NodeOrString;
 use dom::bindings::error::{ErrorResult, Fallible};
 use dom::bindings::error::Error::{NotSupported, InvalidCharacter, Security};
@@ -45,6 +46,7 @@ use dom::element::{ElementTypeId, ActivationElementHelpers, FocusElementHelpers}
 use dom::event::{Event, EventBubbles, EventCancelable, EventHelpers};
 use dom::eventtarget::{EventTarget, EventTargetTypeId, EventTargetHelpers};
 use dom::htmlanchorelement::HTMLAnchorElement;
+use dom::htmlbaseelement::HTMLBaseElement;
 use dom::htmlcollection::{HTMLCollection, CollectionFilter};
 use dom::htmlelement::{HTMLElement, HTMLElementTypeId};
 use dom::htmlheadelement::HTMLHeadElement;
@@ -153,6 +155,8 @@ pub struct Document {
     current_parser: MutNullableHeap<JS<ServoHTMLParser>>,
     /// When we should kick off a reflow. This happens during parsing.
     reflow_timeout: Cell<Option<u64>>,
+    /// The cached first `base` element with an `href` attribute.
+    base_element: MutNullableHeap<JS<HTMLBaseElement>>,
 }
 
 impl PartialEq for Document {
@@ -231,7 +235,16 @@ pub trait DocumentHelpers<'a> {
     fn encoding_name(self) -> Ref<'a, DOMString>;
     fn is_html_document(self) -> bool;
     fn is_fully_active(self) -> bool;
+    /// https://dom.spec.whatwg.org/#concept-document-url
     fn url(self) -> Url;
+    /// https://html.spec.whatwg.org/multipage/#fallback-base-url
+    fn fallback_base_url(self) -> Url;
+    /// https://html.spec.whatwg.org/multipage/#document-base-url
+    fn base_url(self) -> Url;
+    /// Returns the first `base` element in the DOM that has an `href` attribute.
+    fn base_element(self) -> Option<Root<HTMLBaseElement>>;
+    /// Refresh the cached first base element in the DOM.
+    fn refresh_base_element(self);
     fn quirks_mode(self) -> QuirksMode;
     fn set_quirks_mode(self, mode: QuirksMode);
     fn set_encoding_name(self, name: DOMString);
@@ -335,11 +348,44 @@ impl<'a> DocumentHelpers<'a> for &'a Document {
         true
     }
 
-    // https://dom.spec.whatwg.org/#dom-document-url
+    // https://dom.spec.whatwg.org/#concept-document-url
     fn url(self) -> Url {
         self.url.clone()
     }
 
+    // https://html.spec.whatwg.org/multipage/#fallback-base-url
+    fn fallback_base_url(self) -> Url {
+        // Step 1: iframe srcdoc (#4767).
+        // Step 2: about:blank with a creator browsing context.
+        // Step 3.
+        self.url()
+    }
+
+    // https://html.spec.whatwg.org/multipage/#document-base-url
+    fn base_url(self) -> Url {
+        match self.base_element() {
+            // Step 1.
+            None => self.fallback_base_url(),
+            // Step 2.
+            Some(base) => base.frozen_base_url(),
+        }
+    }
+
+    /// Returns the first `base` element in the DOM that has an `href` attribute.
+    fn base_element(self) -> Option<Root<HTMLBaseElement>> {
+        self.base_element.get().map(Root::from_rooted)
+    }
+
+    /// Refresh the cached first base element in the DOM.
+    fn refresh_base_element(self) {
+        let base = NodeCast::from_ref(self)
+            .traverse_preorder()
+            .filter_map(HTMLBaseElementCast::to_root)
+            .filter(|element| ElementCast::from_ref(&**element).has_attribute(&atom!("href")))
+            .next();
+        self.base_element.set(base.map(|element| JS::from_ref(&*element)));
+    }
+
     fn quirks_mode(self) -> QuirksMode {
         self.quirks_mode.get()
     }
@@ -1089,6 +1135,7 @@ impl Document {
             loader: DOMRefCell::new(doc_loader),
             current_parser: Default::default(),
             reflow_timeout: Cell::new(None),
+            base_element: Default::default(),
         }
     }
 

servo/components/script/dom/element.rs

@@ -1558,7 +1558,7 @@ impl<'a> VirtualMethods for &'a Element {
             &atom!("style") => {
                 // Modifying the `style` attribute might change style.
                 let doc = document_from_node(*self);
-                let base_url = doc.r().url();
+                let base_url = doc.r().base_url();
                 let value = attr.value();
                 let style = Some(parse_style_attribute(&value, &base_url));
                 *self.style_attribute.borrow_mut() = style;

servo/components/script/dom/htmlbaseelement.rs

@@ -2,16 +2,22 @@
  * 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::attr::{Attr, AttrHelpers};
 use dom::bindings::codegen::Bindings::HTMLBaseElementBinding;
+use dom::bindings::codegen::InheritTypes::ElementCast;
 use dom::bindings::codegen::InheritTypes::HTMLBaseElementDerived;
+use dom::bindings::codegen::InheritTypes::HTMLElementCast;
 use dom::bindings::js::Root;
-use dom::document::Document;
+use dom::document::{Document, DocumentHelpers};
 use dom::eventtarget::{EventTarget, EventTargetTypeId};
-use dom::element::ElementTypeId;
+use dom::element::{ElementTypeId, AttributeHandlers};
 use dom::htmlelement::{HTMLElement, HTMLElementTypeId};
-use dom::node::{Node, NodeTypeId};
+use dom::node::{Node, NodeTypeId, document_from_node};
+use dom::virtualmethods::VirtualMethods;
 use util::str::DOMString;
 
+use url::{Url, UrlParser};
+
 #[dom_struct]
 pub struct HTMLBaseElement {
     htmlelement: HTMLElement
@@ -39,5 +45,62 @@ impl HTMLBaseElement {
         let element = HTMLBaseElement::new_inherited(localName, prefix, document);
         Node::reflect_node(box element, document, HTMLBaseElementBinding::Wrap)
     }
+
+    /// https://html.spec.whatwg.org/multipage/#frozen-base-url
+    pub fn frozen_base_url(&self) -> Url {
+        let href = ElementCast::from_ref(self).get_attribute(&ns!(""), &atom!("href"))
+            .expect("The frozen base url is only defined for base elements \
+                     that have a base url.");
+        let base = document_from_node(self).fallback_base_url();
+        let parsed = UrlParser::new().base_url(&base).parse(&href.value());
+        parsed.unwrap_or(base)
+    }
+
+    /// Update the cached base element in response to adding or removing an
+    /// attribute.
+    pub fn add_remove_attr(&self, attr: &Attr) {
+        if *attr.local_name() == atom!("href") {
+            let document = document_from_node(self);
+            document.refresh_base_element();
+        }
+    }
+
+    /// Update the cached base element in response to binding or unbinding from
+    /// a tree.
+    pub fn bind_unbind(&self, tree_in_doc: bool) {
+        if !tree_in_doc {
+            return;
+        }
+
+        if ElementCast::from_ref(self).has_attribute(&atom!("href")) {
+            let document = document_from_node(self);
+            document.refresh_base_element();
+        }
+    }
 }
 
+impl<'a> VirtualMethods for &'a HTMLBaseElement {
+    fn super_type<'b>(&'b self) -> Option<&'b VirtualMethods> {
+        Some(HTMLElementCast::from_borrowed_ref(self) as &VirtualMethods)
+    }
+
+    fn after_set_attr(&self, attr: &Attr) {
+        self.super_type().unwrap().after_set_attr(attr);
+        self.add_remove_attr(attr);
+    }
+
+    fn before_remove_attr(&self, attr: &Attr) {
+        self.super_type().unwrap().before_remove_attr(attr);
+        self.add_remove_attr(attr);
+    }
+
+    fn bind_to_tree(&self, tree_in_doc: bool) {
+        self.super_type().unwrap().bind_to_tree(tree_in_doc);
+        self.bind_unbind(tree_in_doc);
+    }
+
+    fn unbind_from_tree(&self, tree_in_doc: bool) {
+        self.super_type().unwrap().unbind_from_tree(tree_in_doc);
+        self.bind_unbind(tree_in_doc);
+    }
+}

servo/components/script/dom/virtualmethods.rs

@@ -7,6 +7,7 @@ use dom::bindings::codegen::InheritTypes::ElementCast;
 use dom::bindings::codegen::InheritTypes::HTMLAnchorElementCast;
 use dom::bindings::codegen::InheritTypes::HTMLAreaElementCast;
 use dom::bindings::codegen::InheritTypes::HTMLAppletElementCast;
+use dom::bindings::codegen::InheritTypes::HTMLBaseElementCast;
 use dom::bindings::codegen::InheritTypes::HTMLBodyElementCast;
 use dom::bindings::codegen::InheritTypes::HTMLButtonElementCast;
 use dom::bindings::codegen::InheritTypes::HTMLCanvasElementCast;
@@ -138,6 +139,10 @@ pub fn vtable_for<'a>(node: &'a &'a Node) -> &'a (VirtualMethods + 'a) {
             let element = HTMLAreaElementCast::to_borrowed_ref(node).unwrap();
             element as &'a (VirtualMethods + 'a)
         }
+        NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLBaseElement)) => {
+            let element = HTMLBaseElementCast::to_borrowed_ref(node).unwrap();
+            element as &'a (VirtualMethods + 'a)
+        }
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLBodyElement)) => {
             let element = HTMLBodyElementCast::to_borrowed_ref(node).unwrap();
             element as &'a (VirtualMethods + 'a)