Make animation-name parse none

components/style/matching.rs

@@ -398,7 +398,7 @@ impl<E: TElement> StyleSharingCandidateCache<E> {
             return;
         }
 
-        if box_style.animation_name_count() > 0 {
+        if box_style.specifies_animations() {
             debug!("Failing to insert to the cache: animations");
             return;
         }

components/style/properties/gecko.mako.rs

@@ -1727,15 +1727,14 @@ fn static_assert() {
 
     pub fn set_animation_name(&mut self, v: longhands::animation_name::computed_value::T) {
         use nsstring::nsCString;
+
+        debug_assert!(!v.0.is_empty());
         unsafe { self.gecko.mAnimations.ensure_len(v.0.len()) };
 
-        if v.0.len() > 0 {
-            self.gecko.mAnimationNameCount = v.0.len() as u32;
-            for (servo, gecko) in v.0.into_iter().zip(self.gecko.mAnimations.iter_mut()) {
-                gecko.mName.assign_utf8(&nsCString::from(servo.0.to_string()));
-            }
-        } else {
-            unsafe { self.gecko.mAnimations[0].mName.truncate(); }
+        self.gecko.mAnimationNameCount = v.0.len() as u32;
+        for (servo, gecko) in v.0.into_iter().zip(self.gecko.mAnimations.iter_mut()) {
+            // TODO This is inefficient. We should fix this in bug 1329169.
+            gecko.mName.assign_utf8(&nsCString::from(servo.0.to_string()));
         }
     }
     pub fn animation_name_at(&self, index: usize)

components/style/properties/longhand/box.mako.rs

@@ -776,7 +776,6 @@ ${helpers.single_keyword("overflow-x", "visible hidden scroll auto",
 </%helpers:vector_longhand>
 
 <%helpers:vector_longhand name="animation-name"
-                          allow_empty="True"
                           need_index="True"
                           animatable="False",
                           extra_prefixes="moz webkit"
@@ -797,6 +796,16 @@ ${helpers.single_keyword("overflow-x", "visible hidden scroll auto",
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
     pub struct SpecifiedValue(pub Atom);
 
+    #[inline]
+    pub fn get_initial_value() -> computed_value::T {
+        get_initial_specified_value()
+    }
+
+    #[inline]
+    pub fn get_initial_specified_value() -> SpecifiedValue {
+        SpecifiedValue(atom!(""))
+    }
+
     impl fmt::Display for SpecifiedValue {
         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
             self.0.fmt(f)
@@ -805,7 +814,11 @@ ${helpers.single_keyword("overflow-x", "visible hidden scroll auto",
 
     impl ToCss for SpecifiedValue {
         fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-            dest.write_str(&*self.0.to_string())
+            if self.0 == atom!("") {
+                dest.write_str("none")
+            } else {
+                dest.write_str(&*self.0.to_string())
+            }
         }
     }
 
@@ -813,7 +826,12 @@ ${helpers.single_keyword("overflow-x", "visible hidden scroll auto",
         fn parse(_context: &ParserContext, input: &mut ::cssparser::Parser) -> Result<Self, ()> {
             use cssparser::Token;
             Ok(match input.next() {
-                Ok(Token::Ident(ref value)) if value != "none" => SpecifiedValue(Atom::from(&**value)),
+                Ok(Token::Ident(ref value)) => SpecifiedValue(if value == "none" {
+                    // FIXME We may want to support `@keyframes ""` at some point.
+                    atom!("")
+                } else {
+                    Atom::from(&**value)
+                }),
                 Ok(Token::QuotedString(value)) => SpecifiedValue(Atom::from(&*value)),
                 _ => return Err(()),
             })

components/style/properties/properties.mako.rs

@@ -1295,6 +1295,14 @@ pub mod style_structs {
                 }
             % endif
         % endfor
+
+        % if style_struct.name == "Box":
+            /// Returns whether there is any animation specified with
+            /// animation-name other than `none`.
+            pub fn specifies_animations(&self) -> bool {
+                self.animation_name_iter().any(|name| name.0 != atom!(""))
+            }
+        % endif
     }
 
     % for longhand in style_struct.longhands: