style: Fix elements not being query containers for the pseudo-element they originate. r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D164807

components/style/gecko/selector_parser.rs

@@ -8,6 +8,7 @@ use crate::computed_value_flags::ComputedValueFlags;
 use crate::gecko_bindings::structs::RawServoSelectorList;
 use crate::gecko_bindings::sugar::ownership::{HasBoxFFI, HasFFI, HasSimpleFFI};
 use crate::invalidation::element::document_state::InvalidationMatchingData;
+use crate::properties::ComputedValues;
 use crate::selector_parser::{Direction, HorizontalDirection, SelectorParser};
 use crate::str::starts_with_ignore_ascii_case;
 use crate::string_cache::{Atom, Namespace, WeakAtom, WeakNamespace};
@@ -17,6 +18,7 @@ use cssparser::{CowRcStr, SourceLocation, ToCss, Token};
 use dom::{DocumentState, ElementState};
 use selectors::parser::SelectorParseErrorKind;
 use selectors::SelectorList;
+use servo_arc::Arc;
 use std::fmt;
 use style_traits::{CssWriter, ParseError, StyleParseErrorKind, ToCss as ToCss_};
 
@@ -233,7 +235,7 @@ pub struct SelectorImpl;
 
 /// A set of extra data to carry along with the matching context, either for
 /// selector-matching or invalidation.
-#[derive(Debug, Default)]
+#[derive(Default)]
 pub struct ExtraMatchingData {
     /// The invalidation data to invalidate doc-state pseudo-classes correctly.
     pub invalidation_data: InvalidationMatchingData,
@@ -241,6 +243,10 @@ pub struct ExtraMatchingData {
     /// The invalidation bits from matching container queries. These are here
     /// just for convenience mostly.
     pub cascade_input_flags: ComputedValueFlags,
+
+    /// The style of the originating element in order to evaluate @container
+    /// size queries affecting pseudo-elements.
+    pub originating_element_style: Option<Arc<ComputedValues>>,
 }
 
 impl ::selectors::SelectorImpl for SelectorImpl {

components/style/properties/cascade.rs

@@ -281,7 +281,7 @@ where
     };
 
     let is_root_element = pseudo.is_none() && element.map_or(false, |e| e.is_root());
-    let container_size_query = ContainerSizeQuery::for_option_element(element);
+    let container_size_query = ContainerSizeQuery::for_option_element(element, None);
 
     let mut context = computed::Context::new(
         // We'd really like to own the rules here to avoid refcount traffic, but

components/style/style_resolver.rs

@@ -420,7 +420,7 @@ where
         layout_parent_style: Option<&ComputedValues>,
     ) -> Option<ResolvedStyle> {
         let MatchingResults { rule_node, mut flags } = self.match_pseudo(
-            originating_element_style.style(),
+            &originating_element_style.style.0,
             pseudo,
             VisitedHandlingMode::AllLinksUnvisited,
         )?;
@@ -428,7 +428,7 @@ where
         let mut visited_rules = None;
         if originating_element_style.style().visited_style().is_some() {
             visited_rules = self.match_pseudo(
-                originating_element_style.style(),
+                &originating_element_style.style.0,
                 pseudo,
                 VisitedHandlingMode::RelevantLinkVisited,
             ).map(|results| {
@@ -506,7 +506,7 @@ where
 
     fn match_pseudo(
         &mut self,
-        originating_element_style: &ComputedValues,
+        originating_element_style: &Arc<ComputedValues>,
         pseudo_element: &PseudoElement,
         visited_handling: VisitedHandlingMode,
     ) -> Option<MatchingResults> {
@@ -534,7 +534,7 @@ where
         let bloom_filter = self.context.thread_local.bloom_filter.filter();
         let nth_index_cache = &mut self.context.thread_local.nth_index_cache;
 
-        let mut matching_context = MatchingContext::new_for_visited(
+        let mut matching_context = MatchingContext::<'_, E::Impl>::new_for_visited(
             MatchingMode::ForStatelessPseudoElement,
             Some(bloom_filter),
             Some(nth_index_cache),
@@ -542,6 +542,8 @@ where
             self.context.shared.quirks_mode(),
             NeedsSelectorFlags::Yes,
         );
+        matching_context.extra_data.originating_element_style =
+            Some(originating_element_style.clone());
 
         // NB: We handle animation rules for ::before and ::after when
         // traversing them.

components/style/stylesheets/container_rule.rs

@@ -135,15 +135,26 @@ enum TraversalResult<T> {
     Done(T),
 }
 
-fn traverse_container<E, F, R>(mut e: E, evaluator: F) -> Option<(E, R)>
+fn traverse_container<E, F, R>(
+    mut e: E,
+    originating_element_style: Option<&Arc<ComputedValues>>,
+    evaluator: F,
+) -> Option<(E, R)>
 where
     E: TElement,
-    F: Fn(E) -> TraversalResult<R>,
+    F: Fn(E, Option<&Arc<ComputedValues>>) -> TraversalResult<R>,
 {
-    while let Some(element) = e.traversal_parent() {
+    if originating_element_style.is_some() {
-        match evaluator(element) {
+        match evaluator(e, originating_element_style) {
             TraversalResult::InProgress => {},
-            TraversalResult::StopTraversal => break,
+            TraversalResult::StopTraversal => return None,
+            TraversalResult::Done(result) => return Some((e, result)),
+        }
+    }
+    while let Some(element) = e.traversal_parent() {
+        match evaluator(element, None) {
+            TraversalResult::InProgress => {},
+            TraversalResult::StopTraversal => return None,
             TraversalResult::Done(result) => return Some((element, result)),
         }
         e = element;
@@ -174,15 +185,22 @@ impl ContainerCondition {
     fn valid_container_info<E>(
         &self,
         potential_container: E,
+        originating_element_style: Option<&Arc<ComputedValues>>,
     ) -> TraversalResult<ContainerLookupResult<E>>
     where
         E: TElement,
     {
-        let data = match potential_container.borrow_data() {
+        let data;
-            Some(data) => data,
+        let style = match originating_element_style {
+            Some(s) => s,
+            None => {
+                data = match potential_container.borrow_data() {
+                    Some(d) => d,
                     None => return TraversalResult::InProgress,
                 };
-        let style = data.styles.primary();
+                data.styles.primary()
+            },
+        };
         let wm = style.writing_mode;
         let box_style = style.get_box();
 
@@ -211,11 +229,21 @@ impl ContainerCondition {
     }
 
     /// Performs container lookup for a given element.
-    pub fn find_container<E>(&self, e: E) -> Option<ContainerLookupResult<E>>
+    pub fn find_container<E>(
+        &self,
+        e: E,
+        originating_element_style: Option<&Arc<ComputedValues>>,
+    ) -> Option<ContainerLookupResult<E>>
     where
         E: TElement,
     {
-        match traverse_container(e, |element| self.valid_container_info(element)) {
+        match traverse_container(
+            e,
+            originating_element_style,
+            |element, originating_element_style| {
+                self.valid_container_info(element, originating_element_style)
+            },
+        ) {
             Some((_, result)) => Some(result),
             None => None,
         }
@@ -226,18 +254,19 @@ impl ContainerCondition {
         &self,
         device: &Device,
         element: E,
+        originating_element_style: Option<&Arc<ComputedValues>>,
         invalidation_flags: &mut ComputedValueFlags,
     ) -> KleeneValue
     where
         E: TElement,
     {
-        let result = self.find_container(element);
+        let result = self.find_container(element, originating_element_style);
         let (container, info) = match result {
             Some(r) => (Some(r.element), Some((r.info, r.style))),
             None => (None, None),
         };
         // Set up the lookup for the container in question, as the condition may be using container query lengths.
-        let size_query_container_lookup = ContainerSizeQuery::for_option_element(container);
+        let size_query_container_lookup = ContainerSizeQuery::for_option_element(container, None);
         Context::for_container_query_evaluation(
             device,
             info,
@@ -448,16 +477,24 @@ pub enum ContainerSizeQuery<'a> {
 }
 
 impl<'a> ContainerSizeQuery<'a> {
-    fn evaluate_potential_size_container<E>(e: E) -> TraversalResult<ContainerSizeQueryResult>
+    fn evaluate_potential_size_container<E>(
+        e: E,
+        originating_element_style: Option<&Arc<ComputedValues>>,
+    ) -> TraversalResult<ContainerSizeQueryResult>
     where
         E: TElement,
     {
-        let data = match e.borrow_data() {
+        let data;
-            Some(data) => data,
+        let style = match originating_element_style {
+            Some(s) => s,
+            None => {
+                data = match e.borrow_data() {
+                    Some(d) => d,
                     None => return TraversalResult::InProgress,
                 };
-
+                data.styles.primary()
-        let style = data.styles.primary();
+            },
+        };
         if !style
             .flags
             .contains(ComputedValueFlags::SELF_OR_ANCESTOR_HAS_SIZE_CONTAINER_TYPE)
@@ -494,17 +531,26 @@ impl<'a> ContainerSizeQuery<'a> {
     }
 
     /// Find the query container size for a given element. Meant to be used as a callback for new().
-    fn lookup<E>(element: E) -> ContainerSizeQueryResult
+    fn lookup<E>(
+        element: E,
+        originating_element_style: Option<&Arc<ComputedValues>>,
+    ) -> ContainerSizeQueryResult
     where
         E: TElement + 'a,
     {
-        match traverse_container(element, |e| Self::evaluate_potential_size_container(e)) {
+        match traverse_container(
+            element,
+            originating_element_style,
+            |e, originating_element_style| {
+                Self::evaluate_potential_size_container(e, originating_element_style)
+            },
+        ) {
             Some((container, result)) => {
                 if result.is_complete() {
                     result
                 } else {
                     // Traverse up from the found size container to see if we can get a complete containment.
-                    result.merge(Self::lookup(container))
+                    result.merge(Self::lookup(container, None))
                 }
             },
             None => ContainerSizeQueryResult::default(),
@@ -512,35 +558,51 @@ impl<'a> ContainerSizeQuery<'a> {
     }
 
     /// Create a new instance of the container size query for given element, with a deferred lookup callback.
-    pub fn for_element<E>(element: E) -> Self
+    pub fn for_element<E>(
+        element: E,
+        originating_element_style: Option<&'a Arc<ComputedValues>>,
+    ) -> Self
     where
         E: TElement + 'a,
     {
+        let parent;
+        let data;
+        let style = match originating_element_style {
+            Some(s) => Some(s),
+            None => {
                 // No need to bother if we're the top element.
-        if let Some(parent) = element.traversal_parent() {
+                parent = match element.traversal_parent() {
-            let should_traverse = match parent.borrow_data() {
+                    Some(parent) => parent,
-                Some(data) => {
+                    None => return Self::none(),
-                    let style = data.styles.primary();
+                };
-                    style
+                data = parent.borrow_data();
-                        .flags
+                data.as_ref().map(|data| data.styles.primary())
-                        .contains(ComputedValueFlags::SELF_OR_ANCESTOR_HAS_SIZE_CONTAINER_TYPE)
             },
+        };
+        let should_traverse = match style {
+            Some(style) => style
+                .flags
+                .contains(ComputedValueFlags::SELF_OR_ANCESTOR_HAS_SIZE_CONTAINER_TYPE),
             None => true, // `display: none`, still want to show a correct computed value, so give it a try.
         };
         if should_traverse {
-                return Self::NotEvaluated(Box::new(move || Self::lookup(element)));
+            return Self::NotEvaluated(Box::new(move || {
-            }
+                Self::lookup(element, originating_element_style)
+            }));
         }
         Self::none()
     }
 
     /// Create a new instance, but with optional element.
-    pub fn for_option_element<E>(element: Option<E>) -> Self
+    pub fn for_option_element<E>(
+        element: Option<E>,
+        originating_element_style: Option<&'a Arc<ComputedValues>>,
+    ) -> Self
     where
         E: TElement + 'a,
     {
         if let Some(e) = element {
-            Self::for_element(e)
+            Self::for_element(e, originating_element_style)
         } else {
             Self::none()
         }

components/style/stylist.rs

@@ -966,7 +966,7 @@ impl Stylist {
         element: E,
         pseudo: &PseudoElement,
         rule_inclusion: RuleInclusion,
-        parent_style: &ComputedValues,
+        parent_style: &Arc<ComputedValues>,
         is_probe: bool,
         matching_fn: Option<&dyn Fn(&PseudoElement) -> bool>,
     ) -> Option<Arc<ComputedValues>>
@@ -1105,7 +1105,7 @@ impl Stylist {
         &self,
         guards: &StylesheetGuards,
         element: E,
-        parent_style: &ComputedValues,
+        parent_style: &Arc<ComputedValues>,
         pseudo: &PseudoElement,
         is_probe: bool,
         rule_inclusion: RuleInclusion,
@@ -1125,7 +1125,7 @@ impl Stylist {
         };
 
         let mut declarations = ApplicableDeclarationList::new();
-        let mut matching_context = MatchingContext::new(
+        let mut matching_context = MatchingContext::<'_, E::Impl>::new(
             MatchingMode::ForStatelessPseudoElement,
             None,
             None,
@@ -1134,6 +1134,7 @@ impl Stylist {
         );
 
         matching_context.pseudo_element_matching_fn = matching_fn;
+        matching_context.extra_data.originating_element_style = Some(parent_style.clone());
 
         self.push_applicable_declarations(
             element,
@@ -1155,7 +1156,7 @@ impl Stylist {
         let mut visited_rules = None;
         if parent_style.visited_style().is_some() {
             let mut declarations = ApplicableDeclarationList::new();
-            let mut matching_context = MatchingContext::new_for_visited(
+            let mut matching_context = MatchingContext::<'_, E::Impl>::new_for_visited(
                 MatchingMode::ForStatelessPseudoElement,
                 None,
                 None,
@@ -1164,6 +1165,7 @@ impl Stylist {
                 needs_selector_flags,
             );
             matching_context.pseudo_element_matching_fn = matching_fn;
+            matching_context.extra_data.originating_element_style = Some(parent_style.clone());
 
             self.push_applicable_declarations(
                 element,
@@ -2380,7 +2382,14 @@ impl CascadeData {
                 None => return true,
                 Some(ref c) => c,
             };
-            let matches = condition.matches(stylist.device(), element, &mut context.extra_data.cascade_input_flags).to_bool(/* unknown = */ false);
+            let matches = condition
+                .matches(
+                    stylist.device(),
+                    element,
+                    context.extra_data.originating_element_style.as_ref(),
+                    &mut context.extra_data.cascade_input_flags,
+                )
+                .to_bool(/* unknown = */ false);
             if !matches {
                 return false;
             }