Auto merge of #5840 - Ms2ger:attrvalue-slice, r=SimonSapin

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components/script/dom/attr.rs

@@ -23,6 +23,7 @@ use string_cache::{Atom, Namespace};
 use std::borrow::ToOwned;
 use std::cell::Ref;
 use std::mem;
+use std::ops::Deref;
 
 pub enum AttrSettingType {
     FirstSetAttr,
@@ -70,10 +71,19 @@ impl AttrValue {
             _ => None
         }
     }
+
+    pub fn atom<'a>(&'a self) -> Option<&'a Atom> {
+        match *self {
+            AttrValue::Atom(ref value) => Some(value),
+            _ => None
+        }
+    }
 }
 
-impl Str for AttrValue {
+impl Deref for AttrValue {
-    fn as_slice<'a>(&'a self) -> &'a str {
+    type Target = str;
+
+    fn deref<'a>(&'a self) -> &'a str {
         match *self {
             AttrValue::String(ref value) |
                 AttrValue::TokenList(ref value, _) |
@@ -144,7 +154,7 @@ impl<'a> AttrMethods for JSRef<'a, Attr> {
 
     // https://dom.spec.whatwg.org/#dom-attr-value
     fn Value(self) -> DOMString {
-        self.value().as_slice().to_owned()
+        (**self.value()).to_owned()
     }
 
     // https://dom.spec.whatwg.org/#dom-attr-value
@@ -292,7 +302,7 @@ impl AttrHelpersForLayout for Attr {
     unsafe fn value_ref_forever(&self) -> &'static str {
         // This transmute is used to cheat the lifetime restriction.
         let value = mem::transmute::<&AttrValue, &AttrValue>(self.value.borrow_for_layout());
-        value.as_slice()
+        &**value
     }
 
     #[inline]

components/script/dom/document.rs

@@ -377,7 +377,7 @@ impl<'a> DocumentHelpers<'a> for JSRef<'a, Document> {
                     // FIXME(https://github.com/rust-lang/rust/issues/23338)
                     let attr = attr.r();
                     let value = attr.value();
-                    value.as_slice() == fragid.as_slice()
+                    &**value == &*fragid
                 })
             };
             let doc_node: JSRef<Node> = NodeCast::from_ref(self);
@@ -1324,7 +1324,7 @@ impl<'a> DocumentMethods for JSRef<'a, Document> {
                 // FIXME(https://github.com/rust-lang/rust/issues/23338)
                 let attr = attr.r();
                 let value = attr.value();
-                value.as_slice() == name.as_slice()
+                &**value == &*name
             })
         })
     }

components/script/dom/element.rs

@@ -1365,7 +1365,7 @@ impl<'a> VirtualMethods for JSRef<'a, Element> {
                 let doc = document_from_node(*self).root();
                 let base_url = doc.r().url();
                 let value = attr.value();
-                let style = Some(parse_style_attribute(value.as_slice(), &base_url));
+                let style = Some(parse_style_attribute(&value, &base_url));
                 *self.style_attribute.borrow_mut() = style;
 
                 if node.is_in_doc() {
@@ -1384,8 +1384,8 @@ impl<'a> VirtualMethods for JSRef<'a, Element> {
                 let value = attr.value();
                 if node.is_in_doc() {
                     let doc = document_from_node(*self).root();
-                    if !value.as_slice().is_empty() {
+                    if !value.is_empty() {
-                        let value = Atom::from_slice(value.as_slice());
+                        let value = value.atom().unwrap().clone();
                         doc.r().register_named_element(*self, value);
                     }
                     doc.r().content_changed(node, NodeDamage::NodeStyleDamaged);
@@ -1422,8 +1422,8 @@ impl<'a> VirtualMethods for JSRef<'a, Element> {
                 let value = attr.value();
                 if node.is_in_doc() {
                     let doc = document_from_node(*self).root();
-                    if !value.as_slice().is_empty() {
+                    if !value.is_empty() {
-                        let value = Atom::from_slice(value.as_slice());
+                        let value = value.atom().unwrap().clone();
                         doc.r().unregister_named_element(*self, value);
                     }
                     doc.r().content_changed(node, NodeDamage::NodeStyleDamaged);
@@ -1496,8 +1496,8 @@ impl<'a> style::node::TElement<'a> for JSRef<'a, Element> {
             // This transmute is used to cheat the lifetime restriction.
             // FIXME(https://github.com/rust-lang/rust/issues/23338)
             let attr = attr.r();
-            let value = attr.value();
+            let value: &str = &**attr.value();
-            unsafe { mem::transmute(value.as_slice()) }
+            unsafe { mem::transmute(value) }
         })
     }
     #[allow(unsafe_code)]
@@ -1505,9 +1505,9 @@ impl<'a> style::node::TElement<'a> for JSRef<'a, Element> {
         self.get_attributes(local_name).into_iter().map(|attr| attr.root()).map(|attr| {
             // FIXME(https://github.com/rust-lang/rust/issues/23338)
             let attr = attr.r();
-            let value = attr.value();
+            let value: &str = &**attr.value();
             // This transmute is used to cheat the lifetime restriction.
-            unsafe { mem::transmute(value.as_slice()) }
+            unsafe { mem::transmute(value) }
         }).collect()
     }
     fn get_link(self) -> Option<&'a str> {

components/script/dom/htmlbodyelement.rs

@@ -108,12 +108,12 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLBodyElement> {
                 };
             evtarget.set_event_handler_uncompiled(cx, url, reflector,
                                                   &name[2..],
-                                                  attr.value().as_slice().to_owned());
+                                                  (**attr.value()).to_owned());
         }
 
         match attr.local_name() {
             &atom!("bgcolor") => {
-                self.background_color.set(str::parse_legacy_color(attr.value().as_slice()).ok())
+                self.background_color.set(str::parse_legacy_color(&attr.value()).ok())
             }
             _ => {}
         }

components/script/dom/htmlcanvaselement.rs

@@ -226,11 +226,11 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLCanvasElement> {
         let value = attr.value();
         let recreate = match attr.local_name() {
             &atom!("width") => {
-                self.width.set(parse_unsigned_integer(value.as_slice().chars()).unwrap_or(DEFAULT_WIDTH));
+                self.width.set(parse_unsigned_integer(value.chars()).unwrap_or(DEFAULT_WIDTH));
                 true
             }
             &atom!("height") => {
-                self.height.set(parse_unsigned_integer(value.as_slice().chars()).unwrap_or(DEFAULT_HEIGHT));
+                self.height.set(parse_unsigned_integer(value.chars()).unwrap_or(DEFAULT_HEIGHT));
                 true
             }
             _ => false,

components/script/dom/htmlelement.rs

@@ -203,7 +203,7 @@ impl<'a> HTMLElementCustomAttributeHelpers for JSRef<'a, HTMLElement> {
             // FIXME(https://github.com/rust-lang/rust/issues/23338)
             let attr = attr.r();
             let value = attr.value();
-            value.as_slice().to_owned()
+            (**value).to_owned()
         })
     }
 
@@ -234,7 +234,7 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLElement> {
             let evtarget: JSRef<EventTarget> = EventTargetCast::from_ref(*self);
             evtarget.set_event_handler_uncompiled(cx, url, reflector,
                                                   &name[2..],
-                                                  attr.value().as_slice().to_owned());
+                                                  (**attr.value()).to_owned());
         }
     }
 }

components/script/dom/htmliframeelement.rs

@@ -85,12 +85,12 @@ impl<'a> HTMLIFrameElementHelpers for JSRef<'a, HTMLIFrameElement> {
         let element: JSRef<Element> = ElementCast::from_ref(self);
         element.get_attribute(&ns!(""), &atom!("src")).root().and_then(|src| {
             let url = src.r().value();
-            if url.as_slice().is_empty() {
+            if url.is_empty() {
                 None
             } else {
                 let window = window_from_node(self).root();
                 UrlParser::new().base_url(&window.r().get_url())
-                    .parse(url.as_slice()).ok()
+                    .parse(&url).ok()
             }
         })
     }

components/script/dom/htmlimageelement.rs

@@ -284,7 +284,7 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLImageElement> {
             &atom!("src") => {
                 let window = window_from_node(*self).root();
                 let url = window.r().get_url();
-                self.update_image(Some((attr.value().as_slice().to_owned(), &url)));
+                self.update_image(Some(((**attr.value()).to_owned(), &url)));
             },
             _ => ()
         }

components/script/dom/htmlinputelement.rs

@@ -479,7 +479,7 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLInputElement> {
             }
             &atom!("type") => {
                 let value = attr.value();
-                self.input_type.set(match value.as_slice() {
+                self.input_type.set(match &**value {
                     "button" => InputType::InputButton,
                     "submit" => InputType::InputSubmit,
                     "reset" => InputType::InputReset,
@@ -497,18 +497,18 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLInputElement> {
             }
             &atom!("value") => {
                 if !self.value_changed.get() {
-                    self.textinput.borrow_mut().set_content(attr.value().as_slice().to_owned());
+                    self.textinput.borrow_mut().set_content((**attr.value()).to_owned());
                 }
             }
             &atom!("name") => {
                 if self.input_type.get() == InputType::InputRadio {
                     let value = attr.value();
-                    self.radio_group_updated(Some(value.as_slice()));
+                    self.radio_group_updated(Some(&value));
                 }
             }
             _ if attr.local_name() == &Atom::from_slice("placeholder") => {
                 let value = attr.value();
-                let stripped = value.as_slice().chars()
+                let stripped = value.chars()
                     .filter(|&c| c != '\n' && c != '\r')
                     .collect::<String>();
                 *self.placeholder.borrow_mut() = stripped;

components/script/dom/htmllinkelement.rs

@@ -63,7 +63,7 @@ fn get_attr(element: JSRef<Element>, local_name: &Atom) -> Option<String> {
         // FIXME(https://github.com/rust-lang/rust/issues/23338)
         let e = e.r();
         let value = e.value();
-        value.as_slice().to_owned()
+        (**value).to_owned()
     })
 }
 
@@ -99,7 +99,7 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLLinkElement> {
         match (rel, attr.local_name()) {
             (ref rel, &atom!("href")) | (ref rel, &atom!("media")) => {
                 if is_stylesheet(rel) {
-                    self.handle_stylesheet_url(attr.value().as_slice());
+                    self.handle_stylesheet_url(&attr.value());
                 }
             }
             (_, _) => ()

components/script/dom/htmltablecellelement.rs

@@ -93,12 +93,12 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLTableCellElement> {
 
         match attr.local_name() {
             &atom!("bgcolor") => {
-                self.background_color.set(str::parse_legacy_color(attr.value().as_slice()).ok())
+                self.background_color.set(str::parse_legacy_color(&attr.value()).ok())
             }
             &atom!("colspan") => {
-                self.colspan.set(str::parse_unsigned_integer(attr.value().as_slice().chars()));
+                self.colspan.set(str::parse_unsigned_integer(attr.value().chars()));
             }
-            &atom!("width") => self.width.set(str::parse_length(attr.value().as_slice())),
+            &atom!("width") => self.width.set(str::parse_length(&attr.value())),
             _ => ()
         }
     }

components/script/dom/htmltableelement.rs

@@ -130,18 +130,17 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLTableElement> {
 
         match attr.local_name() {
             &atom!("bgcolor") => {
-                self.background_color.set(str::parse_legacy_color(attr.value().as_slice()).ok())
+                self.background_color.set(str::parse_legacy_color(&attr.value()).ok())
             }
             &atom!("border") => {
                 // According to HTML5 § 14.3.9, invalid values map to 1px.
                 self.border.set(Some(str::parse_unsigned_integer(attr.value()
-                                                                     .as_slice()
                                                                      .chars()).unwrap_or(1)))
             }
             &atom!("cellspacing") => {
-                self.cellspacing.set(str::parse_unsigned_integer(attr.value().as_slice().chars()))
+                self.cellspacing.set(str::parse_unsigned_integer(attr.value().chars()))
             }
-            &atom!("width") => self.width.set(str::parse_length(attr.value().as_slice())),
+            &atom!("width") => self.width.set(str::parse_length(&attr.value())),
             _ => ()
         }
     }

components/script/dom/htmltablerowelement.rs

@@ -74,7 +74,7 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLTableRowElement> {
 
         match attr.local_name() {
             &atom!("bgcolor") => {
-                self.background_color.set(str::parse_legacy_color(attr.value().as_slice()).ok());
+                self.background_color.set(str::parse_legacy_color(&attr.value()).ok());
             },
             _ => ()
         }

components/script/dom/htmltablesectionelement.rs

@@ -72,7 +72,7 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLTableSectionElement> {
 
         match attr.local_name() {
             &atom!("bgcolor") => {
-                self.background_color.set(str::parse_legacy_color(attr.value().as_slice()).ok());
+                self.background_color.set(str::parse_legacy_color(&attr.value()).ok());
             },
             _ => ()
         }

components/script/dom/node.rs

@@ -2254,7 +2254,7 @@ impl<'a> NodeMethods for JSRef<'a, Node> {
                 other_element.attrs().iter().map(|attr| attr.root()).any(|other_attr| {
                     (*attr.r().namespace() == *other_attr.r().namespace()) &&
                     (attr.r().local_name() == other_attr.r().local_name()) &&
-                    (attr.r().value().as_slice() == other_attr.r().value().as_slice())
+                    (**attr.r().value() == **other_attr.r().value())
                 })
             })
         }
@@ -2520,7 +2520,7 @@ impl<'a> style::node::TNode<'a> for JSRef<'a, Node> {
                         // FIXME(https://github.com/rust-lang/rust/issues/23338)
                         let attr = attr.r();
                         let value = attr.value();
-                        test(value.as_slice())
+                        test(&value)
                     })
             },
             NamespaceConstraint::Any => {
@@ -2530,7 +2530,7 @@ impl<'a> style::node::TNode<'a> for JSRef<'a, Node> {
                         // FIXME(https://github.com/rust-lang/rust/issues/23338)
                         let attr = attr.r();
                         let value = attr.value();
-                        test(value.as_slice())
+                        test(&value)
                     })
             }
         }

components/script/parse/html.rs

@@ -215,7 +215,7 @@ impl<'a> Serializable for JSRef<'a, Node> {
                         (qname, value)
                     }).collect::<Vec<_>>();
                     let attr_refs = attrs.iter().map(|&(ref qname, ref value)| {
-                        let ar: AttrRef = (&qname, value.as_slice());
+                        let ar: AttrRef = (&qname, &**value);
                         ar
                     });
                     try!(serializer.start_elem(name.clone(), attr_refs));