servo: Merge #17570 - Implement :visited support for lazy pseudo-elements (from bzbarsky:visited-pseudos); r=jryans

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix https://bugzilla.mozilla.org/show_bug.cgi?id=1364242

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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Source-Repo: https://github.com/servo/servo
Source-Revision: ff19e69d2388725cc15784b12c897c755ab06b6b

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 3f8a4c1f743b5373d812bc451f4abdab9820c9cb

servo/components/script_layout_interface/wrapper_traits.rs

@@ -426,6 +426,7 @@ pub trait ThreadSafeLayoutElement: Clone + Copy + Sized + Debug +
                                    &style_pseudo,
                                    RuleInclusion::All,
                                    data.styles.primary(),
+                                   /* is_probe = */ false,
                                    &ServoMetricsProvider)
                                .unwrap()
                                .clone()

servo/components/style/context.rs

@@ -184,7 +184,7 @@ impl Default for CascadeInputs {
 
 impl CascadeInputs {
     /// Construct inputs from previous cascade results, if any.
-    fn new_from_style(style: &Arc<ComputedValues>) -> Self {
+    pub fn new_from_style(style: &Arc<ComputedValues>) -> Self {
         CascadeInputs {
             rules: style.rules.clone(),
             visited_rules: style.get_visited_style().and_then(|v| v.rules.clone()),
@@ -204,6 +204,11 @@ impl CascadeInputs {
         self.rules.as_mut()
     }
 
+    /// Gets a reference to the rule node, if any.
+    pub fn get_rules(&self) -> Option<&StrongRuleNode> {
+        self.rules.as_ref()
+    }
+
     /// Gets a reference to the rule node. Panic if the element does not have
     /// rule node.
     pub fn rules(&self) -> &StrongRuleNode {

servo/components/style/matching.rs

@@ -151,7 +151,10 @@ impl CascadeVisitedMode {
     fn rules<'a>(&self, inputs: &'a CascadeInputs) -> &'a StrongRuleNode {
         match *self {
             CascadeVisitedMode::Unvisited => inputs.rules(),
-            CascadeVisitedMode::Visited => inputs.visited_rules(),
+            CascadeVisitedMode::Visited => match inputs.get_visited_rules() {
+                Some(rules) => rules,
+                None => inputs.rules(),
+            }
         }
     }
 
@@ -166,7 +169,7 @@ impl CascadeVisitedMode {
     /// Returns the computed values based on the cascade mode.  In visited mode,
     /// visited values are only returned if they already exist.  If they don't,
     /// we fallback to the regular, unvisited styles.
-    fn values<'a>(&self, values: &'a Arc<ComputedValues>) -> &'a Arc<ComputedValues> {
+    pub fn values<'a>(&self, values: &'a Arc<ComputedValues>) -> &'a Arc<ComputedValues> {
         if *self == CascadeVisitedMode::Visited && values.get_visited_style().is_some() {
             return values.visited_style();
         }
@@ -288,10 +291,35 @@ trait PrivateMatchMethods: TElement {
         }
     }
 
+    /// Get the ComputedValues (if any) for our inheritance parent.
+    fn get_inherited_style_and_parent(&self) -> ParentElementAndStyle<Self> {
+        let parent_el = self.inheritance_parent();
+        let parent_data = parent_el.as_ref().and_then(|e| e.borrow_data());
+        let parent_style = parent_data.as_ref().map(|d| {
+            // Sometimes Gecko eagerly styles things without processing
+            // pending restyles first. In general we'd like to avoid this,
+            // but there can be good reasons (for example, needing to
+            // construct a frame for some small piece of newly-added
+            // content in order to do something specific with that frame,
+            // but not wanting to flush all of layout).
+            debug_assert!(cfg!(feature = "gecko") ||
+                          parent_el.unwrap().has_current_styles(d));
+            d.styles.primary()
+        });
+
+        ParentElementAndStyle {
+            element: parent_el,
+            style: parent_style.cloned(),
+        }
+    }
+
     /// A common path for the cascade used by both primary elements and eager
     /// pseudo-elements after collecting the appropriate rules to use.
     ///
     /// `primary_style` is expected to be Some for eager pseudo-elements.
+    ///
+    /// `parent_info` is our style parent and its primary style, if
+    /// it's already been computed.
     fn cascade_with_rules(&self,
                           shared_context: &SharedStyleContext,
                           font_metrics_provider: &FontMetricsProvider,
@@ -299,6 +327,7 @@ trait PrivateMatchMethods: TElement {
                           primary_style: Option<&Arc<ComputedValues>>,
                           cascade_target: CascadeTarget,
                           cascade_visited: CascadeVisitedMode,
+                          parent_info: Option<&ParentElementAndStyle<Self>>,
                           visited_values_to_insert: Option<Arc<ComputedValues>>)
                           -> Arc<ComputedValues> {
         let mut cascade_info = CascadeInfo::new();
@@ -318,23 +347,18 @@ trait PrivateMatchMethods: TElement {
 
         // Grab the inherited values.
         let parent_el;
-        let parent_data;
+        let element_and_style; // So parent_el and style_to_inherit_from are known live.
         let style_to_inherit_from = match cascade_target {
             CascadeTarget::Normal => {
-                parent_el = self.inheritance_parent();
+                let info = match parent_info {
-                parent_data = parent_el.as_ref().and_then(|e| e.borrow_data());
+                    Some(element_and_style) => element_and_style,
-                let parent_style = parent_data.as_ref().map(|d| {
+                    None => {
-                    // Sometimes Gecko eagerly styles things without processing
+                        element_and_style = self.get_inherited_style_and_parent();
-                    // pending restyles first. In general we'd like to avoid this,
+                        &element_and_style
-                    // but there can be good reasons (for example, needing to
+                    }
-                    // construct a frame for some small piece of newly-added
+                };
-                    // content in order to do something specific with that frame,
+                parent_el = info.element;
-                    // but not wanting to flush all of layout).
+                info.style.as_ref().map(|s| cascade_visited.values(s))
-                    debug_assert!(cfg!(feature = "gecko") ||
-                                  parent_el.unwrap().has_current_styles(d));
-                    d.styles.primary()
-                });
-                parent_style.map(|s| cascade_visited.values(s))
             }
             CascadeTarget::EagerPseudo => {
                 parent_el = Some(self.clone());
@@ -391,11 +415,15 @@ trait PrivateMatchMethods: TElement {
     /// pseudo-elements.
     ///
     /// `primary_style` is expected to be Some for eager pseudo-elements.
+    ///
+    /// `parent_info` is our style parent and its primary style, if
+    /// it's already been computed.
     fn cascade_internal(&self,
                         context: &StyleContext<Self>,
                         primary_style: Option<&Arc<ComputedValues>>,
                         primary_inputs: &CascadeInputs,
                         eager_pseudo_inputs: Option<&CascadeInputs>,
+                        parent_info: Option<&ParentElementAndStyle<Self>>,
                         cascade_visited: CascadeVisitedMode)
                         -> Arc<ComputedValues> {
         if let Some(pseudo) = self.implemented_pseudo_element() {
@@ -459,15 +487,19 @@ trait PrivateMatchMethods: TElement {
                                 primary_style,
                                 cascade_target,
                                 cascade_visited,
+                                parent_info,
                                 visited_values_to_insert)
     }
 
     /// Computes values and damage for the primary style of an element, setting
     /// them on the ElementData.
+    ///
+    /// `parent_info` is our style parent and its primary style.
     fn cascade_primary(&self,
                        context: &mut StyleContext<Self>,
                        data: &mut ElementData,
                        important_rules_changed: bool,
+                       parent_info: &ParentElementAndStyle<Self>,
                        cascade_visited: CascadeVisitedMode)
                        -> ChildCascadeRequirement {
         debug!("Cascade primary for {:?}, visited: {:?}", self, cascade_visited);
@@ -485,7 +517,10 @@ trait PrivateMatchMethods: TElement {
             // visited case. This early return is especially important for the
             // `cascade_primary_and_pseudos` path since we rely on the state of
             // some previous matching run.
-            if !cascade_visited.has_rules(primary_inputs) {
+            //
+            // Note that we cannot take this early return if our parent has
+            // visited style, because then we too have visited style.
+            if !cascade_visited.has_rules(primary_inputs) && !parent_info.has_visited_style() {
                 return ChildCascadeRequirement::CanSkipCascade
             }
 
@@ -494,6 +529,7 @@ trait PrivateMatchMethods: TElement {
                                   None,
                                   primary_inputs,
                                   None,
+                                  /* parent_info = */ None,
                                   cascade_visited)
         };
 
@@ -582,6 +618,7 @@ trait PrivateMatchMethods: TElement {
                                   data.styles.get_primary(),
                                   primary_inputs,
                                   Some(pseudo_inputs),
+                                  /* parent_info = */ None,
                                   cascade_visited)
         };
 
@@ -625,6 +662,7 @@ trait PrivateMatchMethods: TElement {
                                      Some(primary_style),
                                      CascadeTarget::Normal,
                                      CascadeVisitedMode::Unvisited,
+                                     /* parent_info = */ None,
                                      None))
     }
 
@@ -877,6 +915,23 @@ trait PrivateMatchMethods: TElement {
 
 impl<E: TElement> PrivateMatchMethods for E {}
 
+/// A struct that holds an element we inherit from and its ComputedValues.
+#[derive(Debug)]
+struct ParentElementAndStyle<E: TElement> {
+    /// Our style parent element.
+    element: Option<E>,
+    /// Element's primary ComputedValues.  Not a borrow because we can't prove
+    /// that the thing hanging off element won't change while we're passing this
+    /// struct around.
+    style: Option<Arc<ComputedValues>>,
+}
+
+impl<E: TElement> ParentElementAndStyle<E> {
+    fn has_visited_style(&self) -> bool {
+        self.style.as_ref().map_or(false, |v| { v.get_visited_style().is_some() })
+    }
+}
+
 /// Collects the outputs of the primary matching process, including the rule
 /// node and other associated data.
 #[derive(Debug)]
@@ -944,13 +999,21 @@ pub trait MatchMethods : TElement {
         let relevant_link_found = primary_results.relevant_link_found;
         if relevant_link_found {
             self.match_primary(context, data, VisitedHandlingMode::RelevantLinkVisited);
+        }
+
+        // Even if there is no relevant link, we need to cascade visited styles
+        // if our parent has visited styles.
+        let parent_and_styles = self.get_inherited_style_and_parent();
+        if relevant_link_found || parent_and_styles.has_visited_style() {
             self.cascade_primary(context, data, important_rules_changed,
+                                 &parent_and_styles,
                                  CascadeVisitedMode::Visited);
         }
 
         // Cascade properties and compute primary values.
         let child_cascade_requirement =
             self.cascade_primary(context, data, important_rules_changed,
+                                 &parent_and_styles,
                                  CascadeVisitedMode::Unvisited);
 
         // Match and cascade eager pseudo-elements.
@@ -1017,10 +1080,13 @@ pub trait MatchMethods : TElement {
         // visited ComputedValues are placed within the regular ComputedValues,
         // which is immutable after the cascade.  If there aren't any visited
         // rules, these calls will return without cascading.
+        let parent_and_styles = self.get_inherited_style_and_parent();
         self.cascade_primary(context, &mut data, important_rules_changed,
+                             &parent_and_styles,
                              CascadeVisitedMode::Visited);
         let child_cascade_requirement =
             self.cascade_primary(context, &mut data, important_rules_changed,
+                                 &parent_and_styles,
                                  CascadeVisitedMode::Unvisited);
         self.cascade_pseudos(context, &mut data, CascadeVisitedMode::Visited);
         self.cascade_pseudos(context, &mut data, CascadeVisitedMode::Unvisited);
@@ -1211,8 +1277,10 @@ pub trait MatchMethods : TElement {
         // Compute rule nodes for eagerly-cascaded pseudo-elements.
         let mut matches_different_pseudos = false;
         SelectorImpl::each_eagerly_cascaded_pseudo_element(|pseudo| {
-            // For pseudo-elements, we only try to match visited rules if there
+            // For eager pseudo-elements, we only try to match visited rules if
-            // are also unvisited rules.  (This matches Gecko's behavior.)
+            // there are also unvisited rules.  (This matches Gecko's behavior
+            // for probing pseudo-elements, and for eager pseudo-elements Gecko
+            // does not try to resolve style if the probe says there isn't any.)
             if visited_handling == VisitedHandlingMode::RelevantLinkVisited &&
                !context.cascade_inputs().pseudos.has(&pseudo) {
                 return
@@ -1587,6 +1655,7 @@ pub trait MatchMethods : TElement {
                                 Some(primary_style),
                                 CascadeTarget::Normal,
                                 CascadeVisitedMode::Unvisited,
+                                /* parent_info = */ None,
                                 None)
     }
 

servo/components/style/stylist.rs

@@ -7,7 +7,7 @@
 use {Atom, LocalName, Namespace};
 use applicable_declarations::{ApplicableDeclarationBlock, ApplicableDeclarationList};
 use bit_vec::BitVec;
-use context::QuirksMode;
+use context::{CascadeInputs, QuirksMode};
 use dom::TElement;
 use element_state::ElementState;
 use error_reporting::create_error_reporter;
@@ -16,6 +16,7 @@ use font_metrics::FontMetricsProvider;
 use gecko_bindings::structs::{nsIAtom, StyleRuleInclusion};
 use invalidation::element::invalidation_map::InvalidationMap;
 use invalidation::media_queries::EffectiveMediaQueryResults;
+use matching::CascadeVisitedMode;
 use media_queries::Device;
 use properties::{self, CascadeFlags, ComputedValues};
 use properties::{AnimationRules, PropertyDeclarationBlock};
@@ -27,7 +28,7 @@ use selector_parser::{SelectorImpl, PseudoElement};
 use selectors::attr::NamespaceConstraint;
 use selectors::bloom::BloomFilter;
 use selectors::matching::{ElementSelectorFlags, matches_selector, MatchingContext, MatchingMode};
-use selectors::matching::AFFECTED_BY_PRESENTATIONAL_HINTS;
+use selectors::matching::{VisitedHandlingMode, AFFECTED_BY_PRESENTATIONAL_HINTS};
 use selectors::parser::{AncestorHashes, Combinator, Component, Selector, SelectorAndHashes};
 use selectors::parser::{SelectorIter, SelectorMethods};
 use selectors::sink::Push;
@@ -679,47 +680,90 @@ impl Stylist {
                                                   element: &E,
                                                   pseudo: &PseudoElement,
                                                   rule_inclusion: RuleInclusion,
-                                                  parent_style: &ComputedValues,
+                                                  parent_style: &Arc<ComputedValues>,
+                                                  is_probe: bool,
                                                   font_metrics: &FontMetricsProvider)
                                                   -> Option<Arc<ComputedValues>>
         where E: TElement,
     {
-        let rule_node =
+        let cascade_inputs =
-            self.lazy_pseudo_rules(guards, element, pseudo, rule_inclusion);
+            self.lazy_pseudo_rules(guards, element, pseudo, is_probe, rule_inclusion);
-        self.compute_pseudo_element_style_with_rulenode(rule_node.as_ref(),
+        self.compute_pseudo_element_style_with_inputs(&cascade_inputs,
-                                                        guards,
+                                                      guards,
-                                                        parent_style,
+                                                      parent_style,
-                                                        font_metrics)
+                                                      font_metrics)
     }
 
-    /// Computes a pseudo-element style lazily using the given rulenode.  This
+    /// Computes a pseudo-element style lazily using the given CascadeInputs.
-    /// can be used for truly lazy pseudo-elements or to avoid redoing selector
+    /// This can be used for truly lazy pseudo-elements or to avoid redoing
-    /// matching for eager pseudo-elements when we need to recompute their style
+    /// selector matching for eager pseudo-elements when we need to recompute
-    /// with a new parent style.
+    /// their style with a new parent style.
-    pub fn compute_pseudo_element_style_with_rulenode(&self,
+    pub fn compute_pseudo_element_style_with_inputs(&self,
-                                                      rule_node: Option<&StrongRuleNode>,
+                                                    inputs: &CascadeInputs,
-                                                      guards: &StylesheetGuards,
+                                                    guards: &StylesheetGuards,
-                                                      parent_style: &ComputedValues,
+                                                    parent_style: &Arc<ComputedValues>,
-                                                      font_metrics: &FontMetricsProvider)
+                                                    font_metrics: &FontMetricsProvider)
-                                                      -> Option<Arc<ComputedValues>>
+                                                    -> Option<Arc<ComputedValues>>
     {
-        let rule_node = match rule_node {
+        // We may have only visited rules in cases when we are actually
-            Some(rule_node) => rule_node,
+        // resolving, not probing, pseudo-element style.
-            None => return None
+        if !inputs.has_rules() && !inputs.has_visited_rules() {
+            return None
+        }
+
+        // We need to compute visited values if we have visited rules or if our
+        // parent has visited values.
+        let visited_values = if inputs.has_visited_rules() || parent_style.get_visited_style().is_some() {
+            // Slightly annoying: we know that inputs has either rules or
+            // visited rules, but we can't do inputs.rules() up front because
+            // maybe it just has visited rules, so can't unwrap_or.
+            let rule_node = match inputs.get_visited_rules() {
+                Some(rules) => rules,
+                None => inputs.rules()
+            };
+            // We want to use the visited bits (if any) from our parent style as
+            // our parent.
+            let mode = CascadeVisitedMode::Visited;
+            let inherited_style = mode.values(parent_style);
+            let computed =
+                properties::cascade(&self.device,
+                                    rule_node,
+                                    guards,
+                                    Some(inherited_style),
+                                    Some(inherited_style),
+                                    None,
+                                    None,
+                                    &create_error_reporter(),
+                                    font_metrics,
+                                    CascadeFlags::empty(),
+                                    self.quirks_mode);
+
+            Some(Arc::new(computed))
+        } else {
+            None
+        };
+
+        // We may not have non-visited rules, if we only had visited ones.  In
+        // that case we want to use the root rulenode for our non-visited rules.
+        let root;
+        let rules = if let Some(rules) = inputs.get_rules() {
+            rules
+        } else {
+            root = self.rule_tree.root();
+            &root
         };
 
         // Read the comment on `precomputed_values_for_pseudo` to see why it's
         // difficult to assert that display: contents nodes never arrive here
         // (tl;dr: It doesn't apply for replaced elements and such, but the
         // computed value is still "contents").
-        // Bug 1364242: We need to add visited support for lazy pseudos
         let computed =
             properties::cascade(&self.device,
-                                rule_node,
+                                rules,
                                 guards,
                                 Some(parent_style),
                                 Some(parent_style),
-                                None,
+                                visited_values,
                                 None,
                                 &create_error_reporter(),
                                 font_metrics,
@@ -729,7 +773,7 @@ impl Stylist {
         Some(Arc::new(computed))
     }
 
-    /// Computes the rule node for a lazily-cascaded pseudo-element.
+    /// Computes the cascade inputs for a lazily-cascaded pseudo-element.
     ///
     /// See the documentation on lazy pseudo-elements in
     /// docs/components/style.md
@@ -737,14 +781,15 @@ impl Stylist {
                                 guards: &StylesheetGuards,
                                 element: &E,
                                 pseudo: &PseudoElement,
+                                is_probe: bool,
                                 rule_inclusion: RuleInclusion)
-                                -> Option<StrongRuleNode>
+                                -> CascadeInputs
         where E: TElement
     {
         let pseudo = pseudo.canonical();
         debug_assert!(pseudo.is_lazy());
         if self.pseudos_map.get(&pseudo).is_none() {
-            return None
+            return CascadeInputs::default()
         }
 
         // Apply the selector flags. We should be in sequential mode
@@ -777,7 +822,7 @@ impl Stylist {
             }
         };
 
-        // Bug 1364242: We need to add visited support for lazy pseudos
+        let mut inputs = CascadeInputs::default();
         let mut declarations = ApplicableDeclarationList::new();
         let mut matching_context =
             MatchingContext::new(MatchingMode::ForStatelessPseudoElement,
@@ -792,19 +837,52 @@ impl Stylist {
                                           &mut declarations,
                                           &mut matching_context,
                                           &mut set_selector_flags);
-        if declarations.is_empty() {
-            return None
-        }
 
-        let rule_node =
+        if !declarations.is_empty() {
-            self.rule_tree.insert_ordered_rules_with_important(
+            let rule_node = self.rule_tree.insert_ordered_rules_with_important(
                 declarations.into_iter().map(|a| a.order_and_level()),
                 guards);
-        if rule_node == self.rule_tree.root() {
+            if rule_node != self.rule_tree.root() {
-            None
+                inputs.set_rules(VisitedHandlingMode::AllLinksUnvisited,
-        } else {
+                                 rule_node);
-            Some(rule_node)
+            }
+        };
+
+        if is_probe && !inputs.has_rules() {
+            // When probing, don't compute visited styles if we have no
+            // unvisited styles.
+            return inputs;
         }
+
+        if matching_context.relevant_link_found {
+            let mut declarations = ApplicableDeclarationList::new();
+            let mut matching_context =
+                MatchingContext::new_for_visited(MatchingMode::ForStatelessPseudoElement,
+                                                 None,
+                                                 VisitedHandlingMode::RelevantLinkVisited,
+                                                 self.quirks_mode);
+            self.push_applicable_declarations(element,
+                                              Some(&pseudo),
+                                              None,
+                                              None,
+                                              AnimationRules(None, None),
+                                              rule_inclusion,
+                                              &mut declarations,
+                                              &mut matching_context,
+                                              &mut set_selector_flags);
+            if !declarations.is_empty() {
+                let rule_node =
+                    self.rule_tree.insert_ordered_rules_with_important(
+                        declarations.into_iter().map(|a| a.order_and_level()),
+                        guards);
+                if rule_node != self.rule_tree.root() {
+                    inputs.set_rules(VisitedHandlingMode::RelevantLinkVisited,
+                                     rule_node);
+                }
+            }
+        }
+
+        inputs
     }
 
     /// Set a given device, which may change the styles that apply to the

servo/ports/geckolib/glue.rs

@@ -10,7 +10,7 @@ use selectors::Element;
 use std::env;
 use std::fmt::Write;
 use std::ptr;
-use style::context::{QuirksMode, SharedStyleContext, StyleContext};
+use style::context::{CascadeInputs, QuirksMode, SharedStyleContext, StyleContext};
 use style::context::ThreadLocalStyleContext;
 use style::data::{ElementData, ElementStyles, RestyleData};
 use style::dom::{AnimationOnlyDirtyDescendants, DirtyDescendants};
@@ -1479,7 +1479,7 @@ pub extern "C" fn Servo_ResolvePseudoStyle(element: RawGeckoElementBorrowed,
         &pseudo,
         RuleInclusion::All,
         &data.styles,
-        ComputedValues::arc_from_borrowed(&inherited_style).map(|v| v.as_ref()),
+        ComputedValues::arc_from_borrowed(&inherited_style),
         &*doc_data,
         is_probe
     );
@@ -1533,7 +1533,7 @@ fn get_pseudo_style(
     pseudo: &PseudoElement,
     rule_inclusion: RuleInclusion,
     styles: &ElementStyles,
-    inherited_styles: Option<&ComputedValues>,
+    inherited_styles: Option<&Arc<ComputedValues>>,
     doc_data: &PerDocumentStyleDataImpl,
     is_probe: bool,
 ) -> Option<Arc<ComputedValues>> {
@@ -1550,20 +1550,20 @@ fn get_pseudo_style(
                         inherited_styles.unwrap_or(styles.primary());
                     let guards = StylesheetGuards::same(guard);
                     let metrics = get_metrics_provider_for_product();
-                    let rule_node = match styles.pseudos.get(&pseudo) {
+                    let inputs = match styles.pseudos.get(&pseudo) {
-                        Some(styles) => styles.rules.as_ref(),
+                        Some(styles) => CascadeInputs::new_from_style(styles),
-                        None => None,
+                        None => return None,
                     };
                     doc_data.stylist
-                        .compute_pseudo_element_style_with_rulenode(
+                        .compute_pseudo_element_style_with_inputs(
-                            rule_node,
+                            &inputs,
                             &guards,
                             inherited_styles,
                             &metrics)
                 },
                 _ => {
                     debug_assert!(inherited_styles.is_none() ||
-                                  ptr::eq(inherited_styles.unwrap(),
+                                  ptr::eq(&**inherited_styles.unwrap(),
                                           &**styles.primary()));
                     styles.pseudos.get(&pseudo).cloned()
                 },
@@ -1572,7 +1572,7 @@ fn get_pseudo_style(
         PseudoElementCascadeType::Precomputed => unreachable!("No anonymous boxes"),
         PseudoElementCascadeType::Lazy => {
             debug_assert!(inherited_styles.is_none() ||
-                          ptr::eq(inherited_styles.unwrap(),
+                          ptr::eq(&**inherited_styles.unwrap(),
                                   &**styles.primary()));
             let base = if pseudo.inherits_from_default_values() {
                 doc_data.default_computed_values()
@@ -1588,6 +1588,7 @@ fn get_pseudo_style(
                     &pseudo,
                     rule_inclusion,
                     base,
+                    is_probe,
                     &metrics)
         },
     };