Add SMIL override cascade level

components/style/dom.rs

@@ -319,6 +319,11 @@ pub trait TElement : Eq + PartialEq + Debug + Hash + Sized + Copy + Clone +
     /// Get this element's style attribute.
     fn style_attribute(&self) -> Option<&Arc<Locked<PropertyDeclarationBlock>>>;
 
+    /// Get this element's SMIL override declarations.
+    fn get_smil_override(&self) -> Option<&Arc<Locked<PropertyDeclarationBlock>>> {
+        None
+    }
+
     /// Get this element's animation rules.
     fn get_animation_rules(&self, _pseudo: Option<&PseudoElement>) -> AnimationRules {
         AnimationRules(None, None)

components/style/matching.rs

@@ -882,6 +882,7 @@ pub trait MatchMethods : TElement {
 
         let stylist = &context.shared.stylist;
         let style_attribute = self.style_attribute();
+        let smil_override = self.get_smil_override();
         let animation_rules = self.get_animation_rules(None);
         let mut rule_nodes_changed = false;
         let bloom = context.thread_local.bloom_filter.filter();
@@ -895,6 +896,7 @@ pub trait MatchMethods : TElement {
         *relations = stylist.push_applicable_declarations(self,
                                                           Some(bloom),
                                                           style_attribute,
+                                                          smil_override,
                                                           animation_rules,
                                                           None,
                                                           &context.shared.guards,
@@ -952,7 +954,9 @@ pub trait MatchMethods : TElement {
             };
             stylist.push_applicable_declarations(self,
                                                  Some(bloom_filter),
-                                                 None, pseudo_animation_rules,
+                                                 None,
+                                                 None,
+                                                 pseudo_animation_rules,
                                                  Some(&pseudo),
                                                  &guards,
                                                  &mut applicable_declarations,

components/style/rule_tree/mod.rs

@@ -254,19 +254,19 @@ impl RuleTree {
         path.parent().unwrap().clone()
     }
 
-    /// Returns new rule node without Animations and Transitions level rules.
+    /// Returns new rule node without rules from declarative animations.
     pub fn remove_animation_and_transition_rules(&self, path: &StrongRuleNode) -> StrongRuleNode {
-        // Return a clone if there is neither animation nor transition level.
+        // Return a clone if there are no animation rules.
         if !path.has_animation_or_transition_rules() {
             return path.clone();
         }
 
-        let iter = path.self_and_ancestors().take_while(|node| node.cascade_level() >= CascadeLevel::Animations);
+        let iter = path.self_and_ancestors().take_while(
+            |node| node.cascade_level() >= CascadeLevel::SMILOverride);
         let mut last = path;
         let mut children = vec![];
         for node in iter {
-            if node.cascade_level() != CascadeLevel::Animations &&
+            if node.cascade_level().is_animation() {
-               node.cascade_level() != CascadeLevel::Transitions {
                 children.push((node.get().source.clone().unwrap(), node.cascade_level()));
             }
             last = node;
@@ -301,6 +301,8 @@ pub enum CascadeLevel {
     AuthorNormal,
     /// Style attribute normal rules.
     StyleAttributeNormal,
+    /// SVG SMIL animations.
+    SMILOverride,
     /// CSS animations and script-generated animations.
     Animations,
     /// Author-supplied important rules.
@@ -333,6 +335,7 @@ impl CascadeLevel {
         match *self {
             CascadeLevel::Transitions |
             CascadeLevel::Animations |
+            CascadeLevel::SMILOverride |
             CascadeLevel::StyleAttributeNormal |
             CascadeLevel::StyleAttributeImportant => true,
             _ => false,
@@ -362,6 +365,17 @@ impl CascadeLevel {
             Importance::Normal
         }
     }
+
+    /// Returns whether this cascade level represents an animation rules.
+    #[inline]
+    pub fn is_animation(&self) -> bool {
+        match *self {
+            CascadeLevel::SMILOverride |
+            CascadeLevel::Animations |
+            CascadeLevel::Transitions => true,
+            _ => false,
+        }
+    }
 }
 
 struct RuleNode {
@@ -780,8 +794,8 @@ impl StrongRuleNode {
     /// Returns true if there is either animation or transition level rule.
     pub fn has_animation_or_transition_rules(&self) -> bool {
         self.self_and_ancestors()
-            .take_while(|node| node.cascade_level() >= CascadeLevel::Animations)
+            .take_while(|node| node.cascade_level() >= CascadeLevel::SMILOverride)
-            .any(|node| matches!(node.cascade_level(), CascadeLevel::Animations | CascadeLevel::Transitions))
+            .any(|node| node.cascade_level().is_animation())
     }
 }
 

components/style/stylist.rs

@@ -510,6 +510,7 @@ impl Stylist {
 
 
         self.push_applicable_declarations(element,
+                                          None,
                                           None,
                                           None,
                                           AnimationRules(None, None),
@@ -631,6 +632,7 @@ impl Stylist {
                                         element: &E,
                                         parent_bf: Option<&BloomFilter>,
                                         style_attribute: Option<&Arc<Locked<PropertyDeclarationBlock>>>,
+                                        smil_override: Option<&Arc<Locked<PropertyDeclarationBlock>>>,
                                         animation_rules: AnimationRules,
                                         pseudo_element: Option<&PseudoElement>,
                                         guards: &StylesheetGuards,
@@ -711,7 +713,17 @@ impl Stylist {
 
             debug!("style attr: {:?}", relations);
 
-            // Step 5: Animations.
+            // Step 5: SMIL override.
+            // Declarations from SVG SMIL animation elements.
+            if let Some(so) = smil_override {
+                Push::push(
+                    applicable_declarations,
+                    ApplicableDeclarationBlock::from_declarations(so.clone(),
+                                                                  CascadeLevel::SMILOverride));
+            }
+            debug!("SMIL: {:?}", relations);
+
+            // Step 6: Animations.
             // The animations sheet (CSS animations, script-generated animations,
             // and CSS transitions that are no longer tied to CSS markup)
             if let Some(anim) = animation_rules.0 {
@@ -722,7 +734,7 @@ impl Stylist {
             }
             debug!("animation: {:?}", relations);
 
-            // Step 6: Author-supplied `!important` rules.
+            // Step 7: Author-supplied `!important` rules.
             map.author.get_all_matching_rules(element,
                                               parent_bf,
                                               applicable_declarations,
@@ -732,7 +744,7 @@ impl Stylist {
 
             debug!("author important: {:?}", relations);
 
-            // Step 7: `!important` style attributes.
+            // Step 8: `!important` style attributes.
             if let Some(sa) = style_attribute {
                 if sa.read_with(guards.author).any_important() {
                     relations |= AFFECTED_BY_STYLE_ATTRIBUTE;
@@ -745,7 +757,7 @@ impl Stylist {
 
             debug!("style attr important: {:?}", relations);
 
-            // Step 8: User `!important` rules.
+            // Step 9: User `!important` rules.
             map.user.get_all_matching_rules(element,
                                             parent_bf,
                                             applicable_declarations,
@@ -758,7 +770,7 @@ impl Stylist {
             debug!("skipping non-agent rules");
         }
 
-        // Step 9: UA `!important` rules.
+        // Step 10: UA `!important` rules.
         map.user_agent.get_all_matching_rules(element,
                                               parent_bf,
                                               applicable_declarations,
@@ -768,7 +780,7 @@ impl Stylist {
 
         debug!("UA important: {:?}", relations);
 
-        // Step 10: Transitions.
+        // Step 11: Transitions.
         // The transitions sheet (CSS transitions that are tied to CSS markup)
         if let Some(anim) = animation_rules.1 {
             Push::push(