Convert element name to be stored as atom instead of string.

src/components/script/dom/element.rs

@@ -32,6 +32,7 @@ use style;
 use servo_util::namespace;
 use servo_util::namespace::{Namespace, Null};
 use servo_util::str::{DOMString, null_str_as_empty_ref, split_html_space_chars};
+use servo_util::atom::Atom;
 
 use std::ascii::StrAsciiExt;
 use std::cell::{Cell, RefCell};
@@ -40,7 +41,7 @@ use std::mem;
 #[deriving(Encodable)]
 pub struct Element {
     pub node: Node,
-    pub local_name: DOMString,     // TODO: This should be an atom, not a DOMString.
+    pub local_name: Atom,
     pub namespace: Namespace,
     pub prefix: Option<DOMString>,
     pub attrs: RefCell<Vec<JS<Attr>>>,
@@ -145,7 +146,7 @@ impl Element {
     pub fn new_inherited(type_id: ElementTypeId, local_name: DOMString, namespace: Namespace, prefix: Option<DOMString>, document: &JSRef<Document>) -> Element {
         Element {
             node: Node::new_inherited(ElementNodeTypeId(type_id), document),
-            local_name: local_name,
+            local_name: Atom::from_slice(local_name.as_slice()),
             namespace: namespace,
             prefix: prefix,
             attrs: RefCell::new(vec!()),
@@ -460,7 +461,7 @@ impl<'a> ElementMethods for JSRef<'a, Element> {
     }
 
     fn LocalName(&self) -> DOMString {
-        self.local_name.clone()
+        self.local_name.as_slice().to_string()
     }
 
     // http://dom.spec.whatwg.org/#dom-element-prefix

src/components/script/dom/htmlcollection.rs

@@ -10,6 +10,7 @@ use dom::bindings::utils::{Reflectable, Reflector, reflect_dom_object};
 use dom::element::{Element, AttributeHandlers};
 use dom::node::{Node, NodeHelpers};
 use dom::window::Window;
+use servo_util::atom::Atom;
 use servo_util::namespace::Namespace;
 use servo_util::str::{DOMString, split_html_space_chars};
 
@@ -60,7 +61,7 @@ impl HTMLCollection {
     pub fn by_tag_name(window: &JSRef<Window>, root: &JSRef<Node>, tag: DOMString)
                        -> Temporary<HTMLCollection> {
         struct TagNameFilter {
-            tag: DOMString
+            tag: Atom
         }
         impl CollectionFilter for TagNameFilter {
             fn filter(&self, elem: &JSRef<Element>, _root: &JSRef<Node>) -> bool {
@@ -68,7 +69,7 @@ impl HTMLCollection {
             }
         }
         let filter = TagNameFilter {
-            tag: tag
+            tag: Atom::from_slice(tag.as_slice())
         };
         HTMLCollection::create(window, root, box filter)
     }
@@ -76,7 +77,7 @@ impl HTMLCollection {
     pub fn by_tag_name_ns(window: &JSRef<Window>, root: &JSRef<Node>, tag: DOMString,
                           namespace: Namespace) -> Temporary<HTMLCollection> {
         struct TagNameNSFilter {
-            tag: DOMString,
+            tag: Atom,
             namespace: Namespace
         }
         impl CollectionFilter for TagNameNSFilter {
@@ -85,7 +86,7 @@ impl HTMLCollection {
             }
         }
         let filter = TagNameNSFilter {
-            tag: tag,
+            tag: Atom::from_slice(tag.as_slice()),
             namespace: namespace
         };
         HTMLCollection::create(window, root, box filter)

src/components/script/dom/htmlserializer.rs

@@ -129,7 +129,7 @@ fn serialize_elem(elem: &JSRef<Element>, open_elements: &mut Vec<String>, html:
     }
 
     if !elem.deref().is_void() {
-        open_elements.push(elem.deref().local_name.clone());
+        open_elements.push(elem.deref().local_name.as_slice().to_string());
     }
 }
 

src/components/script/dom/node.rs

@@ -1273,7 +1273,7 @@ impl Node {
             ElementNodeTypeId(..) => {
                 let element: &JSRef<Element> = ElementCast::to_ref(node).unwrap();
                 let element = element.deref();
-                let element = build_element_from_tag(element.local_name.clone(),
+                let element = build_element_from_tag(element.local_name.as_slice().into_string(),
                     element.namespace.clone(), &*document);
                 NodeCast::from_temporary(element)
             },

src/components/util/atom.rs

@@ -0,0 +1,44 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * 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/. */
+
+// Provides a wrapper around the Atom type in the string cache
+// crate. It's needed so that it can implement the Encodable
+// trait which is required by Servo.
+
+use serialize::{Encoder, Encodable};
+use std::fmt;
+use string_cache::atom;
+
+#[deriving(Clone, Eq, PartialEq)]
+pub struct Atom {
+    atom: atom::Atom,
+}
+
+impl Atom {
+    #[inline(always)]
+    pub fn from_slice(string_to_add: &str) -> Atom {
+        Atom {
+            atom: atom::Atom::from_slice(string_to_add)
+        }
+    }
+}
+
+impl Str for Atom {
+    #[inline(always)]
+    fn as_slice<'t>(&'t self) -> &'t str {
+        self.atom.as_slice()
+    }
+}
+
+impl fmt::Show for Atom {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{:s}", self.atom.as_slice())
+    }
+}
+
+impl<E, S: Encoder<E>> Encodable<S, E> for Atom {
+    fn encode(&self, _s: &mut S) -> Result<(), E> {
+        Ok(())
+    }
+}

src/components/util/util.rs

@@ -29,7 +29,9 @@ extern crate sync;
 extern crate task_info;
 extern crate std_time = "time";
 extern crate std_url = "url";
+extern crate string_cache;
 
+pub mod atom;
 pub mod cache;
 pub mod debug_utils;
 pub mod geometry;