stylo: Implement GetSpecificity for ServoStyleRule

components/selectors/parser.rs

@@ -201,23 +201,6 @@ impl<Impl: SelectorImpl> SelectorList<Impl> {
     pub fn from_vec(v: Vec<Selector<Impl>>) -> Self {
         SelectorList(v.into_iter().map(SelectorAndHashes::new).collect())
     }
-
-    pub fn to_css_from_index<W>(&self, from_index: usize, dest: &mut W)
-        -> fmt::Result where W: fmt::Write {
-        let mut iter = self.0.iter().skip(from_index);
-
-        let first = match iter.next() {
-            Some(f) => f,
-            None => return Ok(()),
-        };
-
-        first.selector.to_css(dest)?;
-        for selector_and_hashes in iter {
-            dest.write_str(", ")?;
-            selector_and_hashes.selector.to_css(dest)?;
-        }
-        Ok(())
-    }
 }
 
 /// Copied from Gecko, who copied it from WebKit. Note that increasing the
@@ -714,7 +697,15 @@ impl<Impl: SelectorImpl> Debug for LocalName<Impl> {
 
 impl<Impl: SelectorImpl> ToCss for SelectorList<Impl> {
     fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-        self.to_css_from_index(/* from_index = */ 0, dest)
+        let mut iter = self.0.iter();
+        let first = iter.next()
+            .expect("Empty SelectorList, should contain at least one selector");
+        first.selector.to_css(dest)?;
+        for selector_and_hashes in iter {
+            dest.write_str(", ")?;
+            selector_and_hashes.selector.to_css(dest)?;
+        }
+        Ok(())
     }
 }
 

components/style/gecko/generated/bindings.rs

@@ -2112,11 +2112,17 @@ extern "C" {
                                            result: *mut nsAString);
 }
 extern "C" {
-    pub fn Servo_StyleRule_GetSelectorTextFromIndex(rule:
+    pub fn Servo_StyleRule_GetSelectorTextAtIndex(rule:
                                                         RawServoStyleRuleBorrowed,
                                                     index: u32,
                                                     result: *mut nsAString);
 }
+extern "C" {
+    pub fn Servo_StyleRule_GetSpecificityAtIndex(rule:
+                                                     RawServoStyleRuleBorrowed,
+                                                 index: u32,
+                                                 specificity: *mut u64);
+}
 extern "C" {
     pub fn Servo_StyleRule_GetSelectorCount(rule: RawServoStyleRuleBorrowed,
                                             count: *mut u32);

ports/geckolib/glue.rs

@@ -1187,14 +1187,15 @@ pub extern "C" fn Servo_StyleRule_GetSelectorText(rule: RawServoStyleRuleBorrowe
 }
 
 #[no_mangle]
-pub extern "C" fn Servo_StyleRule_GetSelectorTextFromIndex(rule: RawServoStyleRuleBorrowed,
+pub extern "C" fn Servo_StyleRule_GetSelectorTextAtIndex(rule: RawServoStyleRuleBorrowed,
-                                                           aSelectorIndex: u32,
+                                                         index: u32,
-                                                           result: *mut nsAString) {
+                                                         result: *mut nsAString) {
     read_locked_arc(rule, |rule: &StyleRule| {
-        rule.selectors.to_css_from_index(
+        let index = index as usize;
-            aSelectorIndex as usize,
+        if index >= rule.selectors.0.len() {
-            unsafe { result.as_mut().unwrap() }
+            return;
-        ).unwrap();
+        }
+        rule.selectors.0[index].selector.to_css(unsafe { result.as_mut().unwrap() }).unwrap();
     })
 }
 
@@ -1205,6 +1206,21 @@ pub extern "C" fn Servo_StyleRule_GetSelectorCount(rule: RawServoStyleRuleBorrow
     })
 }
 
+#[no_mangle]
+pub extern "C" fn Servo_StyleRule_GetSpecificityAtIndex(rule: RawServoStyleRuleBorrowed,
+                                                        index: u32,
+                                                        specificity: *mut u64) {
+    read_locked_arc(rule, |rule: &StyleRule| {
+        let mut specificity =  unsafe { specificity.as_mut().unwrap() };
+        let index = index as usize;
+        if index >= rule.selectors.0.len() {
+            *specificity = 0;
+            return;
+        }
+        *specificity = rule.selectors.0[index].selector.specificity() as u64;
+    })
+}
+
 #[no_mangle]
 pub extern "C" fn Servo_ImportRule_GetHref(rule: RawServoImportRuleBorrowed, result: *mut nsAString) {
     read_locked_arc(rule, |rule: &ImportRule| {