auto merge of #1202 : SimonSapin/servo/link-selectors, r=jdm

All links are considered "unvisited" for now.

In particular, this fixes the UA stylesheet rule that underlines links.

4 files changed, 50 insertions, 2 deletions

diff --git a/src/components/script/dom/element.rs b/src/components/script/dom/element.rs
index 24644e514af..1901278b40d 100644
--- a/src/components/script/dom/element.rs
+++ b/src/components/script/dom/element.rs
@@ -130,6 +130,18 @@ impl ElementLike for Element {
 
         return value;
     }
+
+    fn get_link<'a>(&'a self) -> Option<&'a str> {
+        // FIXME: This is HTML only.
+        match self.node.type_id {
+            // http://www.whatwg.org/specs/web-apps/current-work/multipage/selectors.html#selector-link
+            ElementNodeTypeId(HTMLAnchorElementTypeId) |
+            ElementNodeTypeId(HTMLAreaElementTypeId) |
+            ElementNodeTypeId(HTMLLinkElementTypeId)
+            => self.get_attr("href"),
+            _ => None,
+        }
+    }
 }
 
 impl<'self> Element {
diff --git a/src/components/style/selector_matching.rs b/src/components/style/selector_matching.rs
index a3fddb8c13d..7e93387f83b 100644
--- a/src/components/style/selector_matching.rs
+++ b/src/components/style/selector_matching.rs
@@ -241,6 +241,28 @@ fn matches_simple_selector<N: TreeNode<T>, T: TreeNodeRefAsElement<N, E>, E: Ele
             attr_value.ends_with(value.as_slice())
         },
 
+
+        AnyLink => {
+            do element.with_imm_element_like |element: &E| {
+                element.get_link().is_some()
+            }
+        }
+        Link => {
+            do element.with_imm_element_like |element: &E| {
+                match element.get_link() {
+                    Some(url) => !url_is_visited(url),
+                    None => false,
+                }
+            }
+        }
+        Visited => {
+            do element.with_imm_element_like |element: &E| {
+                match element.get_link() {
+                    Some(url) => url_is_visited(url),
+                    None => false,
+                }
+            }
+        }
         FirstChild => matches_first_child(element),
 
         Negation(ref negated) => {
@@ -249,6 +271,13 @@ fn matches_simple_selector<N: TreeNode<T>, T: TreeNodeRefAsElement<N, E>, E: Ele
     }
 }
 
+fn url_is_visited(_url: &str) -> bool {
+    // FIXME: implement this.
+    // This function will probably need to take a "session"
+    // or something containing browsing history as an additional parameter.
+    false
+}
+
 #[inline]
 fn matches_first_child<N: TreeNode<T>, T: TreeNodeRefAsElement<N, E>, E: ElementLike>(
         element: &T) -> bool {
diff --git a/src/components/style/selectors.rs b/src/components/style/selectors.rs
index 1589625f61a..9fee4f8fbc9 100644
--- a/src/components/style/selectors.rs
+++ b/src/components/style/selectors.rs
@@ -58,12 +58,15 @@ pub enum SimpleSelector {
     AttrSuffixMatch(AttrSelector, ~str),  // [foo$=bar]
 
     // Pseudo-classes
+    Negation(~[SimpleSelector]),
+    AnyLink,
+    Link,
+    Visited,
     FirstChild,
 //    Empty,
 //    Root,
 //    Lang(~str),
 //    NthChild(i32, i32),
-    Negation(~[SimpleSelector]),
     // ...
 }
 
@@ -181,7 +184,7 @@ fn compute_specificity(mut selector: &CompoundSelector,
                 &ClassSelector(*)
                 | &AttrExists(*) | &AttrEqual(*) | &AttrIncludes(*) | &AttrDashMatch(*)
                 | &AttrPrefixMatch(*) | &AttrSubstringMatch(*) | &AttrSuffixMatch(*)
-                | &FirstChild
+                | &AnyLink | &Link | &Visited | &FirstChild
 //                | &Empty | &Root | &Lang(*) | &NthChild(*)
                 => specificity.class_like_selectors += 1,
                 &NamespaceSelector(*) => (),
@@ -420,6 +423,9 @@ fn parse_attribute_selector(content: ~[ComponentValue], namespaces: &NamespaceMa
 
 fn parse_simple_pseudo_class(name: &str) -> Option<SimpleSelector> {
     match name.to_ascii_lower().as_slice() {
+        "any-link" => Some(AnyLink),
+        "link" => Some(Link),
+        "visited" => Some(Visited),
         "first-child" => Some(FirstChild),
 //        "root" => Some(Root),
 //        "empty" => Some(Empty),
diff --git a/src/components/util/tree.rs b/src/components/util/tree.rs
index f2a80342655..4a156cfa6ca 100644
--- a/src/components/util/tree.rs
+++ b/src/components/util/tree.rs
@@ -349,4 +349,5 @@ pub trait TreeNode<Ref: TreeNodeRef<Self>> {
 pub trait ElementLike {
     fn get_local_name<'a>(&'a self) -> &'a str;
     fn get_attr<'a>(&'a self, name: &str) -> Option<&'a str>;
+    fn get_link<'a>(&'a self) -> Option<&'a str>;
 }