style/invalidation/element/
relative_selector.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5//! Invalidation of element styles relative selectors.
6
7use crate::data::ElementData;
8use crate::dom::{TElement, TNode};
9#[cfg(feature = "gecko")]
10use crate::gecko_bindings::structs::ServoElementSnapshotTable;
11use crate::invalidation::element::element_wrapper::ElementWrapper;
12use crate::invalidation::element::invalidation_map::{
13    AdditionalRelativeSelectorInvalidationMap, Dependency, DependencyInvalidationKind,
14    InvalidationMap, NormalDependencyInvalidationKind, RelativeDependencyInvalidationKind,
15    ScopeDependencyInvalidationKind, TSStateForInvalidation,
16};
17use crate::invalidation::element::invalidator::{
18    note_scope_dependency_force_at_subject, DescendantInvalidationLists, Invalidation,
19    InvalidationProcessor, InvalidationResult, InvalidationVector, SiblingTraversalMap,
20    TreeStyleInvalidator,
21};
22use crate::invalidation::element::restyle_hints::RestyleHint;
23use crate::invalidation::element::state_and_attributes::{
24    check_dependency, dependency_may_be_relevant, invalidated_descendants, invalidated_self,
25    invalidated_sibling, push_invalidation, should_process_descendants,
26};
27#[cfg(feature = "servo")]
28use crate::selector_parser::SnapshotMap as ServoElementSnapshotTable;
29use crate::stylist::{CascadeData, Stylist};
30use dom::ElementState;
31use rustc_hash::FxHashMap;
32use selectors::matching::{
33    early_reject_by_local_name, matches_selector, ElementSelectorFlags, MatchingContext,
34    MatchingForInvalidation, MatchingMode, NeedsSelectorFlags, QuirksMode, SelectorCaches,
35    VisitedHandlingMode,
36};
37use selectors::parser::SelectorKey;
38use selectors::OpaqueElement;
39use smallvec::{smallvec, SmallVec};
40use std::ops::DerefMut;
41
42/// Kind of DOM mutation this relative selector invalidation is being carried out in.
43#[derive(Clone, Copy)]
44pub enum DomMutationOperation {
45    /// Insertion operation, can cause side effect, but presumed already happened.
46    Insert,
47    /// Append operation, cannot cause side effect.
48    Append,
49    /// Removal operation, can cause side effect, but presumed already happened. Sibling relationships are destroyed.
50    Remove,
51    /// Invalidating for side effect of a DOM operation, for the previous sibling.
52    SideEffectPrevSibling,
53    /// Invalidating for side effect of a DOM operation, for the next sibling.
54    SideEffectNextSibling,
55}
56
57impl DomMutationOperation {
58    fn accept<E: TElement>(&self, d: &Dependency, e: E) -> bool {
59        match self {
60            Self::Insert | Self::Append | Self::Remove => {
61                !e.relative_selector_search_direction().is_empty()
62            },
63            // `:has(+ .a + .b)` with `.anchor + .a + .remove + .b` - `.a` would be present
64            // in the search path.
65            Self::SideEffectPrevSibling => {
66                !e.relative_selector_search_direction().is_empty()
67                    && d.right_combinator_is_next_sibling()
68            },
69            // If an element is being removed and would cause next-sibling match to happen,
70            // e.g. `:has(+ .a)` with `.anchor + .remove + .a`, `.a` isn't yet searched
71            // for relative selector matching.
72            Self::SideEffectNextSibling => d.dependency_is_relative_with_single_next_sibling(),
73        }
74    }
75
76    fn is_side_effect(&self) -> bool {
77        match self {
78            Self::Insert | Self::Append | Self::Remove => false,
79            Self::SideEffectPrevSibling | Self::SideEffectNextSibling => true,
80        }
81    }
82}
83
84/// Context required to try and optimize away relative dependencies.
85struct OptimizationContext<'a, E: TElement> {
86    sibling_traversal_map: &'a SiblingTraversalMap<E>,
87    quirks_mode: QuirksMode,
88    operation: DomMutationOperation,
89}
90
91impl<'a, E: TElement> OptimizationContext<'a, E> {
92    fn can_be_ignored(
93        &self,
94        is_subtree: bool,
95        element: E,
96        host: Option<OpaqueElement>,
97        dependency: &Dependency,
98        leftmost_collapse_offset: usize,
99    ) -> bool {
100        if is_subtree {
101            // Subtree elements don't have unaffected sibling to look at.
102            return false;
103        }
104        debug_assert!(
105            matches!(
106                dependency.invalidation_kind(),
107                DependencyInvalidationKind::Relative(..)
108            ),
109            "Non-relative selector being evaluated for optimization"
110        );
111        // This optimization predecates on the fact that there may be a sibling that can readily
112        // "take over" this element.
113        let sibling = match self.sibling_traversal_map.prev_sibling_for(&element) {
114            None => {
115                if matches!(self.operation, DomMutationOperation::Append) {
116                    return false;
117                }
118                match self.sibling_traversal_map.next_sibling_for(&element) {
119                    Some(s) => s,
120                    None => return false,
121                }
122            },
123            Some(s) => s,
124        };
125        {
126            // Run through the affected compund.
127            let iter = dependency.selector.iter_from(dependency.selector_offset);
128            for c in iter {
129                if c.has_indexed_selector_in_subject() {
130                    // We do not calculate indices during invalidation as they're wasteful - as a side effect,
131                    // such selectors always return true, breaking this optimization. Note that we only check
132                    // this compound only because the check to skip compares against this element's sibling.
133                    // i.e. Given `:has(:nth-child(2) .foo)`, we'd try to find `.foo`'s sibling, which
134                    // shares `:nth-child` up the selector.
135                    return false;
136                }
137            }
138        }
139        let dependency_is_rightmost = dependency.selector_offset == 0;
140        if !dependency_is_rightmost {
141            let combinator = dependency
142                .selector
143                .combinator_at_match_order(dependency.selector_offset - 1);
144            if combinator.is_ancestor() {
145                // We can safely ignore these, since we're about to traverse the
146                // rest of the affected tree anyway to find the rightmost invalidated element.
147                return true;
148            }
149            if combinator.is_sibling() && matches!(self.operation, DomMutationOperation::Append) {
150                // If we're at the top of the DOM tree being mutated, we can ignore it if the
151                // operation is append - we know we'll cover all the later siblings and their descendants.
152                return true;
153            }
154        }
155
156        // We have a situation like `:has(.item .item + .item + .item)`, where the first element in the sibling
157        // chain position (i.e. The element matched by the second `.item` from the left) mutates. By the time we
158        // get here, we've collapsed the 4 dependencies for each of `.item` position into one at the rightmost
159        // position. Before we look for a standin, we need to find which `.item` this element matches - Doing
160        // that would generate more work than it saves.
161        if dependency_is_rightmost
162            && leftmost_collapse_offset != dependency.selector_offset
163            && self
164                .sibling_traversal_map
165                .next_sibling_for(&element)
166                .is_some()
167        {
168            return false;
169        }
170
171        let mut caches = SelectorCaches::default();
172        let mut matching_context = MatchingContext::new(
173            MatchingMode::Normal,
174            None,
175            &mut caches,
176            self.quirks_mode,
177            NeedsSelectorFlags::No,
178            MatchingForInvalidation::Yes,
179        );
180        matching_context.current_host = host;
181        let sibling_matches = matches_selector(
182            &dependency.selector,
183            dependency.selector_offset,
184            None,
185            &sibling,
186            &mut matching_context,
187        );
188        if sibling_matches {
189            // Remember that at this point, we know that the combinator to the right of this
190            // compound is a sibling combinator. Effectively, we've found a standin for the
191            // element we're mutating.
192            // e.g. Given `:has(... .a ~ .b ...)`, we're the mutating element matching `... .a`,
193            // if we find a sibling that matches the `... .a`, it can stand in for us.
194            debug_assert!(
195                dependency.next.is_some(),
196                "No relative selector outer dependency?"
197            );
198            return dependency.next.as_ref().is_some_and(|deps| {
199                // ... However, if the standin sibling can be the anchor, we can't skip it, since
200                // that sibling should be invlidated to become the anchor.
201                let next = &deps.as_ref().slice()[0];
202                !matches_selector(
203                    &next.selector,
204                    next.selector_offset,
205                    None,
206                    &sibling,
207                    &mut matching_context,
208                )
209            });
210        }
211        // Ok, there's no standin element - but would this element have matched the upstream
212        // selector anyway? If we don't, either the match exists somewhere far from us
213        // (In which case our mutation doesn't really matter), or it doesn't exist at all,
214        // so we can just skip the invalidation.
215        let (combinator, prev_offset) = {
216            let mut iter = dependency.selector.iter_from(dependency.selector_offset);
217            let mut o = dependency.selector_offset;
218            while iter.next().is_some() {
219                o += 1;
220            }
221            let combinator = iter.next_sequence();
222            o += 1;
223            debug_assert!(
224                combinator.is_some(),
225                "Should at least see a relative combinator"
226            );
227            (combinator.unwrap(), o)
228        };
229        if combinator.is_sibling() && prev_offset >= dependency.selector.len() - 1 {
230            // Hit the relative combinator - we don't have enough information to
231            // see if there's going to be a downstream match.
232            return false;
233        }
234        !matches_selector(
235            &dependency.selector,
236            dependency.selector_offset,
237            None,
238            &element,
239            &mut matching_context,
240        )
241    }
242}
243
244/// Overall invalidator for handling relative selector invalidations.
245pub struct RelativeSelectorInvalidator<'a, 'b, E>
246where
247    E: TElement + 'a,
248{
249    /// Element triggering the invalidation.
250    pub element: E,
251    /// Quirks mode of the current invalidation.
252    pub quirks_mode: QuirksMode,
253    /// Snapshot containing changes to invalidate against.
254    /// Can be None if it's a DOM mutation.
255    pub snapshot_table: Option<&'b ServoElementSnapshotTable>,
256    /// Callback to trigger when the subject element is invalidated.
257    pub invalidated: fn(E, &InvalidationResult),
258    /// The traversal map that should be used to process invalidations.
259    pub sibling_traversal_map: SiblingTraversalMap<E>,
260    /// Marker for 'a lifetime.
261    pub _marker: ::std::marker::PhantomData<&'a ()>,
262}
263
264struct RelativeSelectorInvalidation<'a> {
265    host: Option<OpaqueElement>,
266    kind: RelativeDependencyInvalidationKind,
267    dependency: &'a Dependency,
268}
269
270type ElementDependencies<'a> = SmallVec<[(Option<OpaqueElement>, &'a Dependency); 1]>;
271type Dependencies<'a, E> = SmallVec<[(E, ElementDependencies<'a>); 1]>;
272type AlreadyInvalidated<'a, E> = SmallVec<[AlreadyInvalidatedEntry<'a, E>; 2]>;
273
274struct AlreadyInvalidatedEntry<'a, E>
275where
276    E: TElement + 'a,
277{
278    /// Element where the invalidation will begin.
279    element: E,
280    /// The current shadow host.
281    host: Option<OpaqueElement>,
282    /// Dependency chain for this invalidation.
283    dependency: &'a Dependency,
284    /// The offset, of the leftmost dependencies that this
285    /// invalidation collapsed. See the `update()` function
286    /// for more information.
287    leftmost_collapse_offset: usize,
288}
289
290impl<'a, E> AlreadyInvalidatedEntry<'a, E>
291where
292    E: TElement + 'a,
293{
294    fn new(element: E, host: Option<OpaqueElement>, dependency: &'a Dependency) -> Self {
295        Self {
296            element,
297            host,
298            dependency,
299            leftmost_collapse_offset: dependency.selector_offset,
300        }
301    }
302
303    /// Update this invalidation with a new invalidation that may collapse with it.
304    fn update(&mut self, element: E, host: Option<OpaqueElement>, dependency: &'a Dependency) {
305        // This dependency should invalidate the same way - Collapse the invalidation
306        // to a more general case so we don't do duplicate work.
307        // e.g. For `:has(.item .item + .item + .item)`, since the anchor would be located
308        // in the ancestor chain for any invalidation triggered by any `.item` compound,
309        // 4 entries can collapse into one - but keep track of the leftmost offset.
310        if self.dependency.selector_offset > dependency.selector_offset {
311            *self = Self {
312                element,
313                host,
314                dependency,
315                leftmost_collapse_offset: self.leftmost_collapse_offset,
316            };
317        } else if self.leftmost_collapse_offset < dependency.selector_offset {
318            self.leftmost_collapse_offset = dependency.selector_offset;
319        }
320    }
321}
322
323/// Interface for collecting relative selector dependencies.
324pub struct RelativeSelectorDependencyCollector<'a, E>
325where
326    E: TElement,
327{
328    /// Dependencies that need to run through the normal invalidation that may generate
329    /// a relative selector invalidation.
330    dependencies: FxHashMap<E, ElementDependencies<'a>>,
331    /// Dependencies that created an invalidation right away.
332    invalidations: AlreadyInvalidated<'a, E>,
333    /// The top element in the subtree being invalidated.
334    top: E,
335    /// Optional context that will be used to try and skip invalidations
336    /// by running selector matches.
337    optimization_context: Option<OptimizationContext<'a, E>>,
338}
339
340type Invalidations<'a> = SmallVec<[RelativeSelectorInvalidation<'a>; 1]>;
341type InnerInvalidations<'a, E> = SmallVec<[(E, RelativeSelectorInvalidation<'a>); 1]>;
342
343struct ToInvalidate<'a, E: TElement + 'a> {
344    /// Dependencies to run through normal invalidator.
345    dependencies: Dependencies<'a, E>,
346    /// Dependencies already invalidated.
347    invalidations: Invalidations<'a>,
348}
349
350impl<'a, E: TElement + 'a> Default for ToInvalidate<'a, E> {
351    fn default() -> Self {
352        Self {
353            dependencies: Dependencies::default(),
354            invalidations: Invalidations::default(),
355        }
356    }
357}
358
359fn invalidation_can_collapse(
360    a: &Dependency,
361    b: &Dependency,
362    allow_indexed_selectors: bool,
363) -> bool {
364    // We want to detect identical dependencies that occur at different
365    // compounds but has the identical compound in the same selector,
366    // e.g. :has(.item .item).
367
368    // If they trigger different invalidations, they shouldn't be collapsed.
369    if a.relative_invalidation_kind() != b.relative_invalidation_kind() {
370        return false;
371    }
372
373    // Not in the same selector, trivially skipped.
374    if SelectorKey::new(&a.selector) != SelectorKey::new(&b.selector) {
375        return false;
376    }
377
378    // Check that this is in the same nesting.
379    // TODO(dshin): @scope probably brings more subtleties...
380    let mut a_next = a.next.as_ref();
381    let mut b_next = b.next.as_ref();
382    while let (Some(a_deps), Some(b_deps)) = (a_next, b_next) {
383        // This is a bit subtle - but we don't need to do the checks we do at higher levels.
384        // Cases like `:is(.item .foo) :is(.item .foo)` where `.item` invalidates would
385        // point to different dependencies, pointing to the same outer selector, but
386        // differing in selector offset.
387        let a_nexts = a_deps.as_ref().slice();
388        let b_nexts = b_deps.as_ref().slice();
389        if a_nexts.is_empty() || b_nexts.is_empty() {
390            // Can happen when we get out to empty @scope() rules.
391            // If they're both empty, we can just do nothing for both.
392            return a_nexts.is_empty() == b_nexts.is_empty();
393        }
394        let a_n = &a_nexts[0];
395        let b_n = &b_nexts[0];
396        if SelectorKey::new(&a_n.selector) != SelectorKey::new(&b_n.selector) {
397            return false;
398        }
399        a_next = a_n.next.as_ref();
400        b_next = b_n.next.as_ref();
401    }
402    if a_next.is_some() || b_next.is_some() {
403        return false;
404    }
405
406    // Ok, now, do the compounds actually match?
407    // This can get expensive quickly, but we're assuming that:
408    //
409    //   * In most cases, authors don't generally duplicate compounds in a selector, so
410    //     this fails quickly
411    //   * In cases where compounds are duplicated, reducing the number of invalidations
412    //     has a payoff that offsets the comparison cost
413    //
414    // Note, `.a.b` != `.b.a` - doesn't affect correctness, though.
415    // TODO(dshin): Caching this may be worth it as well?
416    let mut a_iter = a.selector.iter_from(a.selector_offset);
417    let mut b_iter = b.selector.iter_from(b.selector_offset);
418    loop {
419        let a_component = a_iter.next();
420        let b_component = b_iter.next();
421
422        if a_component != b_component {
423            return false;
424        }
425        let Some(component) = a_component else {
426            return true;
427        };
428        if !allow_indexed_selectors && component.has_indexed_selector_in_subject() {
429            // The element's positioning matters, so can't collapse.
430            return false;
431        }
432    }
433}
434
435impl<'a, E> RelativeSelectorDependencyCollector<'a, E>
436where
437    E: TElement,
438{
439    fn new(top: E, optimization_context: Option<OptimizationContext<'a, E>>) -> Self {
440        Self {
441            dependencies: FxHashMap::default(),
442            invalidations: AlreadyInvalidated::default(),
443            top,
444            optimization_context,
445        }
446    }
447
448    fn insert_invalidation(
449        &mut self,
450        element: E,
451        dependency: &'a Dependency,
452        host: Option<OpaqueElement>,
453    ) {
454        let in_subtree = element != self.top;
455        if let Some(entry) = self.invalidations.iter_mut().find(|entry| {
456            // If we're in the subtree of DOM manipulation - worrying the about positioning of this element
457            // is irrelevant, because the DOM structure is either completely new or about to go away.
458            let both_in_subtree = in_subtree && entry.element != self.top;
459            // If we're considering the same element for invalidation, their evaluation of the indexed selector
460            // is identical by definition.
461            let same_element = element == entry.element;
462            invalidation_can_collapse(
463                dependency,
464                entry.dependency,
465                both_in_subtree || same_element,
466            )
467        }) {
468            entry.update(element, host, dependency)
469        } else {
470            self.invalidations
471                .push(AlreadyInvalidatedEntry::new(element, host, dependency));
472        }
473    }
474
475    /// Add this dependency, if it is unique (i.e. Different outer dependency or same outer dependency
476    /// but requires a different invalidation traversal).
477    pub fn add_dependency(
478        &mut self,
479        dependency: &'a Dependency,
480        element: E,
481        host: Option<OpaqueElement>,
482    ) {
483        match dependency.invalidation_kind() {
484            DependencyInvalidationKind::FullSelector => unreachable!(),
485            DependencyInvalidationKind::Normal(..) | DependencyInvalidationKind::Scope(..) => {
486                self.dependencies
487                    .entry(element)
488                    .or_default()
489                    .push((host, dependency));
490            },
491            DependencyInvalidationKind::Relative(kind) => {
492                debug_assert!(
493                    dependency.next.is_some(),
494                    "Orphaned inner relative selector?"
495                );
496                if element != self.top
497                    && matches!(
498                        kind,
499                        RelativeDependencyInvalidationKind::Parent
500                            | RelativeDependencyInvalidationKind::PrevSibling
501                            | RelativeDependencyInvalidationKind::EarlierSibling
502                    )
503                {
504                    return;
505                }
506                if early_reject_by_local_name(
507                    &dependency.selector,
508                    dependency.selector_offset,
509                    &element,
510                ) {
511                    return;
512                }
513                self.insert_invalidation(element, dependency, host);
514            },
515        };
516    }
517
518    /// Get the dependencies in a list format.
519    fn get(self) -> ToInvalidate<'a, E> {
520        let mut result = ToInvalidate::default();
521        for invalidation in self.invalidations {
522            match invalidation.dependency.invalidation_kind() {
523                DependencyInvalidationKind::FullSelector => unreachable!(),
524                DependencyInvalidationKind::Normal(_) | DependencyInvalidationKind::Scope(_) => {
525                    unreachable!("Inner selector in invalidation?")
526                },
527                DependencyInvalidationKind::Relative(kind) => {
528                    if let Some(context) = self.optimization_context.as_ref() {
529                        if context.can_be_ignored(
530                            invalidation.element != self.top,
531                            invalidation.element,
532                            invalidation.host,
533                            invalidation.dependency,
534                            invalidation.leftmost_collapse_offset,
535                        ) {
536                            continue;
537                        }
538                    }
539                    let dependency = &invalidation.dependency.next.as_ref().unwrap().slice()[0];
540                    result.invalidations.push(RelativeSelectorInvalidation {
541                        kind,
542                        host: invalidation.host,
543                        dependency,
544                    });
545                    // We move the invalidation up to the top of the subtree to avoid unnecessary traveral, but
546                    // this means that we need to take ancestor-earlier sibling invalidations into account, as
547                    // they'd look into earlier siblings of the top of the subtree as well.
548                    if invalidation.element != self.top
549                        && matches!(
550                            kind,
551                            RelativeDependencyInvalidationKind::AncestorEarlierSibling
552                                | RelativeDependencyInvalidationKind::AncestorPrevSibling
553                        )
554                    {
555                        result.invalidations.push(RelativeSelectorInvalidation {
556                            kind: if matches!(
557                                kind,
558                                RelativeDependencyInvalidationKind::AncestorPrevSibling
559                            ) {
560                                RelativeDependencyInvalidationKind::PrevSibling
561                            } else {
562                                RelativeDependencyInvalidationKind::EarlierSibling
563                            },
564                            host: invalidation.host,
565                            dependency,
566                        });
567                    }
568                },
569            };
570        }
571        for (key, element_dependencies) in self.dependencies {
572            // At least for now, we don't try to optimize away dependencies emitted from nested selectors.
573            result.dependencies.push((key, element_dependencies));
574        }
575        result
576    }
577
578    fn collect_all_dependencies_for_element(
579        &mut self,
580        element: E,
581        scope: Option<OpaqueElement>,
582        quirks_mode: QuirksMode,
583        map: &'a InvalidationMap,
584        additional_relative_selector_invalidation_map: &'a AdditionalRelativeSelectorInvalidationMap,
585        operation: DomMutationOperation,
586    ) {
587        element.id().map(|v| {
588            if let Some(v) = map.id_to_selector.get(v, quirks_mode) {
589                for dependency in v {
590                    if !operation.accept(dependency, element) {
591                        continue;
592                    }
593                    self.add_dependency(dependency, element, scope);
594                }
595            }
596        });
597        element.each_class(|v| {
598            if let Some(v) = map.class_to_selector.get(v, quirks_mode) {
599                for dependency in v {
600                    if !operation.accept(dependency, element) {
601                        continue;
602                    }
603                    self.add_dependency(dependency, element, scope);
604                }
605            }
606        });
607        element.each_custom_state(|v| {
608            if let Some(v) = map.custom_state_affecting_selectors.get(v) {
609                for dependency in v {
610                    if !operation.accept(dependency, element) {
611                        continue;
612                    }
613                    self.add_dependency(dependency, element, scope);
614                }
615            }
616        });
617        element.each_attr_name(|v| {
618            if let Some(v) = map.other_attribute_affecting_selectors.get(v) {
619                for dependency in v {
620                    if !operation.accept(dependency, element) {
621                        continue;
622                    }
623                    self.add_dependency(dependency, element, scope);
624                }
625            }
626        });
627        let state = element.state();
628        map.state_affecting_selectors.lookup_with_additional(
629            element,
630            quirks_mode,
631            None,
632            &[],
633            ElementState::empty(),
634            |dependency| {
635                if !dependency.state.intersects(state) {
636                    return true;
637                }
638                if !operation.accept(&dependency.dep, element) {
639                    return true;
640                }
641                self.add_dependency(&dependency.dep, element, scope);
642                true
643            },
644        );
645
646        additional_relative_selector_invalidation_map
647            .ts_state_to_selector
648            .lookup_with_additional(
649                element,
650                quirks_mode,
651                None,
652                &[],
653                ElementState::empty(),
654                |dependency| {
655                    if !operation.accept(&dependency.dep, element) {
656                        return true;
657                    }
658                    // This section contain potential optimization for not running full invalidation -
659                    // consult documentation in `TSStateForInvalidation`.
660                    if dependency.state.may_be_optimized() {
661                        if operation.is_side_effect() {
662                            // Side effect operations act on element not being mutated, so they can't
663                            // change the match outcome of these optimizable pseudoclasses.
664                            return true;
665                        }
666                        debug_assert!(
667                            self.optimization_context.is_some(),
668                            "Optimization context not available for DOM mutation?"
669                        );
670                        if dependency.state.contains(TSStateForInvalidation::EMPTY)
671                            && element.first_element_child().is_some()
672                        {
673                            return true;
674                        }
675
676                        let sibling_traversal_map = self
677                            .optimization_context
678                            .as_ref()
679                            .unwrap()
680                            .sibling_traversal_map;
681                        if dependency
682                            .state
683                            .contains(TSStateForInvalidation::NTH_EDGE_FIRST)
684                            && sibling_traversal_map.prev_sibling_for(&element).is_some()
685                        {
686                            return true;
687                        }
688
689                        if dependency
690                            .state
691                            .contains(TSStateForInvalidation::NTH_EDGE_LAST)
692                            && sibling_traversal_map.next_sibling_for(&element).is_some()
693                        {
694                            return true;
695                        }
696                    }
697                    self.add_dependency(&dependency.dep, element, scope);
698                    true
699                },
700            );
701
702        if let Some(v) = additional_relative_selector_invalidation_map
703            .type_to_selector
704            .get(element.local_name())
705        {
706            for dependency in v {
707                if !operation.accept(dependency, element) {
708                    continue;
709                }
710                self.add_dependency(dependency, element, scope);
711            }
712        }
713
714        for dependency in &additional_relative_selector_invalidation_map.any_to_selector {
715            if !operation.accept(dependency, element) {
716                continue;
717            }
718            self.add_dependency(dependency, element, scope);
719        }
720    }
721
722    fn is_empty(&self) -> bool {
723        self.invalidations.is_empty() && self.dependencies.is_empty()
724    }
725}
726
727impl<'a, 'b, E> RelativeSelectorInvalidator<'a, 'b, E>
728where
729    E: TElement + 'a,
730{
731    /// Gather relative selector dependencies for the given element, and invalidate as necessary.
732    #[inline(never)]
733    pub fn invalidate_relative_selectors_for_this<F>(
734        self,
735        stylist: &'a Stylist,
736        mut gather_dependencies: F,
737    ) where
738        F: FnMut(
739            &E,
740            Option<OpaqueElement>,
741            &'a CascadeData,
742            QuirksMode,
743            &mut RelativeSelectorDependencyCollector<'a, E>,
744        ),
745    {
746        let mut collector = RelativeSelectorDependencyCollector::new(self.element, None);
747        stylist.for_each_cascade_data_with_scope(self.element, |data, scope| {
748            let map = data.relative_invalidation_map_attributes();
749            if !map.used {
750                return;
751            }
752            gather_dependencies(
753                &self.element,
754                scope.map(|e| e.opaque()),
755                data,
756                self.quirks_mode,
757                &mut collector,
758            );
759        });
760        if collector.is_empty() {
761            return;
762        }
763        self.invalidate_from_dependencies(collector.get());
764    }
765
766    /// Gather relative selector dependencies for the given element (And its subtree) that mutated, and invalidate as necessary.
767    #[inline(never)]
768    pub fn invalidate_relative_selectors_for_dom_mutation(
769        self,
770        subtree: bool,
771        stylist: &'a Stylist,
772        inherited_search_path: ElementSelectorFlags,
773        operation: DomMutationOperation,
774    ) {
775        let mut collector = RelativeSelectorDependencyCollector::new(
776            self.element,
777            if operation.is_side_effect() {
778                None
779            } else {
780                Some(OptimizationContext {
781                    sibling_traversal_map: &self.sibling_traversal_map,
782                    quirks_mode: self.quirks_mode,
783                    operation,
784                })
785            },
786        );
787        let mut traverse_subtree = false;
788        self.element.apply_selector_flags(inherited_search_path);
789        stylist.for_each_cascade_data_with_scope(self.element, |data, scope| {
790            let map_attributes = data.relative_invalidation_map_attributes();
791            if !map_attributes.used {
792                return;
793            }
794            let map = data.relative_selector_invalidation_map();
795            traverse_subtree |= map_attributes.needs_ancestors_traversal;
796            collector.collect_all_dependencies_for_element(
797                self.element,
798                scope.map(|e| e.opaque()),
799                self.quirks_mode,
800                map,
801                map_attributes,
802                operation,
803            );
804        });
805
806        if subtree && traverse_subtree {
807            for node in self.element.as_node().dom_descendants() {
808                let descendant = match node.as_element() {
809                    Some(e) => e,
810                    None => continue,
811                };
812                descendant.apply_selector_flags(inherited_search_path);
813                stylist.for_each_cascade_data_with_scope(descendant, |data, scope| {
814                    let map_attributes = data.relative_invalidation_map_attributes();
815                    if !map_attributes.used {
816                        return;
817                    }
818                    let map = data.relative_selector_invalidation_map();
819                    collector.collect_all_dependencies_for_element(
820                        descendant,
821                        scope.map(|e| e.opaque()),
822                        self.quirks_mode,
823                        map,
824                        map_attributes,
825                        operation,
826                    );
827                });
828            }
829        }
830        if collector.is_empty() {
831            return;
832        }
833        self.invalidate_from_dependencies(collector.get());
834    }
835
836    /// Carry out complete invalidation triggered by a relative selector invalidation.
837    fn invalidate_from_dependencies(&self, to_invalidate: ToInvalidate<'a, E>) {
838        for (element, dependencies) in to_invalidate.dependencies {
839            let mut selector_caches = SelectorCaches::default();
840            let mut processor = RelativeSelectorInnerInvalidationProcessor::new(
841                self.quirks_mode,
842                self.snapshot_table,
843                &dependencies,
844                &mut selector_caches,
845                &self.sibling_traversal_map,
846            );
847            TreeStyleInvalidator::new(element, None, &mut processor).invalidate();
848            for (element, invalidation) in processor.take_invalidations() {
849                self.invalidate_upwards(element, &invalidation);
850            }
851        }
852        for invalidation in to_invalidate.invalidations {
853            self.invalidate_upwards(self.element, &invalidation);
854        }
855    }
856
857    fn invalidate_upwards(&self, element: E, invalidation: &RelativeSelectorInvalidation<'a>) {
858        // This contains the main reason for why relative selector invalidation is handled
859        // separately - It travels ancestor and/or earlier sibling direction.
860        match invalidation.kind {
861            RelativeDependencyInvalidationKind::Parent => {
862                element.parent_element().map(|e| {
863                    if !Self::in_search_direction(
864                        &e,
865                        ElementSelectorFlags::RELATIVE_SELECTOR_SEARCH_DIRECTION_ANCESTOR,
866                    ) {
867                        return;
868                    }
869                    self.handle_anchor(e, invalidation.dependency, invalidation.host);
870                });
871            },
872            RelativeDependencyInvalidationKind::Ancestors => {
873                let mut parent = element.parent_element();
874                while let Some(par) = parent {
875                    if !Self::in_search_direction(
876                        &par,
877                        ElementSelectorFlags::RELATIVE_SELECTOR_SEARCH_DIRECTION_ANCESTOR,
878                    ) {
879                        return;
880                    }
881                    self.handle_anchor(par, invalidation.dependency, invalidation.host);
882                    parent = par.parent_element();
883                }
884            },
885            RelativeDependencyInvalidationKind::PrevSibling => {
886                self.sibling_traversal_map
887                    .prev_sibling_for(&element)
888                    .map(|e| {
889                        if !Self::in_search_direction(
890                            &e,
891                            ElementSelectorFlags::RELATIVE_SELECTOR_SEARCH_DIRECTION_SIBLING,
892                        ) {
893                            return;
894                        }
895                        self.handle_anchor(e, invalidation.dependency, invalidation.host);
896                    });
897            },
898            RelativeDependencyInvalidationKind::AncestorPrevSibling => {
899                let mut parent = element.parent_element();
900                while let Some(par) = parent {
901                    if !Self::in_search_direction(
902                        &par,
903                        ElementSelectorFlags::RELATIVE_SELECTOR_SEARCH_DIRECTION_ANCESTOR,
904                    ) {
905                        return;
906                    }
907                    par.prev_sibling_element().map(|e| {
908                        if !Self::in_search_direction(
909                            &e,
910                            ElementSelectorFlags::RELATIVE_SELECTOR_SEARCH_DIRECTION_SIBLING,
911                        ) {
912                            return;
913                        }
914                        self.handle_anchor(e, invalidation.dependency, invalidation.host);
915                    });
916                    parent = par.parent_element();
917                }
918            },
919            RelativeDependencyInvalidationKind::EarlierSibling => {
920                let mut sibling = self.sibling_traversal_map.prev_sibling_for(&element);
921                while let Some(sib) = sibling {
922                    if !Self::in_search_direction(
923                        &sib,
924                        ElementSelectorFlags::RELATIVE_SELECTOR_SEARCH_DIRECTION_SIBLING,
925                    ) {
926                        return;
927                    }
928                    self.handle_anchor(sib, invalidation.dependency, invalidation.host);
929                    sibling = sib.prev_sibling_element();
930                }
931            },
932            RelativeDependencyInvalidationKind::AncestorEarlierSibling => {
933                let mut parent = element.parent_element();
934                while let Some(par) = parent {
935                    if !Self::in_search_direction(
936                        &par,
937                        ElementSelectorFlags::RELATIVE_SELECTOR_SEARCH_DIRECTION_ANCESTOR,
938                    ) {
939                        return;
940                    }
941                    let mut sibling = par.prev_sibling_element();
942                    while let Some(sib) = sibling {
943                        if !Self::in_search_direction(
944                            &sib,
945                            ElementSelectorFlags::RELATIVE_SELECTOR_SEARCH_DIRECTION_SIBLING,
946                        ) {
947                            return;
948                        }
949                        self.handle_anchor(sib, invalidation.dependency, invalidation.host);
950                        sibling = sib.prev_sibling_element();
951                    }
952                    parent = par.parent_element();
953                }
954            },
955        }
956    }
957
958    /// Is this element in the direction of the given relative selector search path?
959    fn in_search_direction(element: &E, desired: ElementSelectorFlags) -> bool {
960        element
961            .relative_selector_search_direction()
962            .intersects(desired)
963    }
964
965    /// Handle a potential relative selector anchor.
966    fn handle_anchor(
967        &self,
968        element: E,
969        outer_dependency: &Dependency,
970        host: Option<OpaqueElement>,
971    ) {
972        let is_rightmost = Self::is_subject(outer_dependency);
973        if (is_rightmost
974            && !element.has_selector_flags(ElementSelectorFlags::ANCHORS_RELATIVE_SELECTOR))
975            || (!is_rightmost
976                && !element.has_selector_flags(
977                    ElementSelectorFlags::ANCHORS_RELATIVE_SELECTOR_NON_SUBJECT,
978                ))
979        {
980            // If it was never a relative selector anchor, don't bother.
981            return;
982        }
983        let mut selector_caches = SelectorCaches::default();
984        let matching_context = MatchingContext::<'_, E::Impl>::new_for_visited(
985            MatchingMode::Normal,
986            None,
987            &mut selector_caches,
988            VisitedHandlingMode::AllLinksVisitedAndUnvisited,
989            self.quirks_mode,
990            NeedsSelectorFlags::No,
991            MatchingForInvalidation::Yes,
992        );
993        let mut data = match element.mutate_data() {
994            Some(data) => data,
995            None => return,
996        };
997        let mut processor = RelativeSelectorOuterInvalidationProcessor {
998            element,
999            host,
1000            data: data.deref_mut(),
1001            dependency: outer_dependency,
1002            matching_context,
1003            traversal_map: &self.sibling_traversal_map,
1004        };
1005        let result = TreeStyleInvalidator::new(element, None, &mut processor).invalidate();
1006        (self.invalidated)(element, &result);
1007    }
1008
1009    /// Does this relative selector dependency have its relative selector in the subject position?
1010    fn is_subject(outer_dependency: &Dependency) -> bool {
1011        debug_assert!(
1012            matches!(
1013                outer_dependency.invalidation_kind(),
1014                DependencyInvalidationKind::Normal(_) | DependencyInvalidationKind::Scope(_)
1015            ),
1016            "Outer selector of relative selector is relative?"
1017        );
1018
1019        if let Some(x) = outer_dependency.next.as_ref() {
1020            // We only care to ensure that we're the subject in the outermost selector of the current
1021            // selector - Crossing over a scope invalidation would mean moving into a selector inside
1022            // the current scope block
1023            if matches!(
1024                outer_dependency.invalidation_kind(),
1025                DependencyInvalidationKind::Normal(..)
1026            ) && !Self::is_subject(&x.as_ref().slice()[0])
1027            {
1028                // Not subject in outer selector.
1029                return false;
1030            }
1031        }
1032        outer_dependency
1033            .selector
1034            .is_rightmost(outer_dependency.selector_offset)
1035    }
1036}
1037
1038/// Blindly invalidate everything outside of a relative selector.
1039/// Consider `:is(.a :has(.b) .c ~ .d) ~ .e .f`, where .b gets deleted.
1040/// Since the tree mutated, we cannot rely on snapshots.
1041pub struct RelativeSelectorOuterInvalidationProcessor<'a, 'b, E: TElement> {
1042    /// Element being invalidated.
1043    pub element: E,
1044    /// The current shadow host, if any.
1045    pub host: Option<OpaqueElement>,
1046    /// Data for the element being invalidated.
1047    pub data: &'a mut ElementData,
1048    /// Dependency to be processed.
1049    pub dependency: &'b Dependency,
1050    /// Matching context to use for invalidation.
1051    pub matching_context: MatchingContext<'a, E::Impl>,
1052    /// Traversal map for this invalidation.
1053    pub traversal_map: &'a SiblingTraversalMap<E>,
1054}
1055
1056impl<'a, 'b: 'a, E: 'a> InvalidationProcessor<'b, 'a, E>
1057    for RelativeSelectorOuterInvalidationProcessor<'a, 'b, E>
1058where
1059    E: TElement,
1060{
1061    fn invalidates_on_pseudo_element(&self) -> bool {
1062        true
1063    }
1064
1065    fn check_outer_dependency(
1066        &mut self,
1067        _dependency: &Dependency,
1068        _element: E,
1069        _: Option<OpaqueElement>,
1070    ) -> bool {
1071        // At this point, we know a relative selector invalidated, and are ignoring them.
1072        true
1073    }
1074
1075    fn matching_context(&mut self) -> &mut MatchingContext<'a, E::Impl> {
1076        &mut self.matching_context
1077    }
1078
1079    fn sibling_traversal_map(&self) -> &SiblingTraversalMap<E> {
1080        self.traversal_map
1081    }
1082
1083    fn collect_invalidations(
1084        &mut self,
1085        element: E,
1086        _self_invalidations: &mut InvalidationVector<'b>,
1087        descendant_invalidations: &mut DescendantInvalidationLists<'b>,
1088        sibling_invalidations: &mut InvalidationVector<'b>,
1089    ) -> bool {
1090        debug_assert_eq!(element, self.element);
1091        debug_assert!(
1092            self.matching_context.matching_for_invalidation(),
1093            "Not matching for invalidation?"
1094        );
1095
1096        // Ok, this element can potentially an anchor to the given dependency.
1097        // Before we do the potentially-costly ancestor/earlier sibling traversal,
1098        // See if it can actuall be an anchor by trying to match the "rest" of the selector
1099        // outside and to the left of `:has` in question.
1100        // e.g. Element under consideration can only be the anchor to `:has` in
1101        // `.foo .bar ~ .baz:has()`, iff it matches `.foo .bar ~ .baz`.
1102        let invalidated_self = {
1103            let mut invalidated = false;
1104            let mut dependencies_to_invalidate: SmallVec<[&Dependency; 1]> =
1105                smallvec![self.dependency];
1106            while let Some(d) = dependencies_to_invalidate.pop() {
1107                debug_assert!(
1108                    matches!(
1109                        d.invalidation_kind(),
1110                        DependencyInvalidationKind::Normal(_)
1111                            | DependencyInvalidationKind::Scope(_)
1112                    ),
1113                    "Unexpected dependency kind"
1114                );
1115                if !dependency_may_be_relevant(d, &element, false) {
1116                    continue;
1117                }
1118                if !matches_selector(
1119                    &d.selector,
1120                    d.selector_offset,
1121                    None,
1122                    &element,
1123                    self.matching_context(),
1124                ) {
1125                    continue;
1126                }
1127
1128                let invalidation_kind = d.invalidation_kind();
1129
1130                if let DependencyInvalidationKind::Scope(scope_kind) = invalidation_kind {
1131                    if d.selector.is_rightmost(d.selector_offset) {
1132                        if scope_kind == ScopeDependencyInvalidationKind::ScopeEnd {
1133                            let invalidations = note_scope_dependency_force_at_subject(
1134                                d,
1135                                self.matching_context.current_host,
1136                                self.matching_context.scope_element,
1137                                false,
1138                            );
1139                            descendant_invalidations
1140                                .dom_descendants
1141                                .extend(invalidations);
1142
1143                            invalidated |= true;
1144                        } else if let Some(ref next) = d.next {
1145                            dependencies_to_invalidate.extend(next.as_ref().slice());
1146                        }
1147                        continue;
1148                    }
1149                }
1150
1151                if matches!(
1152                    invalidation_kind,
1153                    DependencyInvalidationKind::Normal(NormalDependencyInvalidationKind::Element)
1154                ) {
1155                    if let Some(ref deps) = d.next {
1156                        // Normal dependencies should only have one next
1157                        dependencies_to_invalidate.push(&deps.as_ref().slice()[0]);
1158                        continue;
1159                    }
1160                    invalidated |= true;
1161                    continue;
1162                }
1163                debug_assert_ne!(d.selector_offset, 0);
1164                debug_assert_ne!(d.selector_offset, d.selector.len());
1165                let invalidation = Invalidation::new(d, self.host, None);
1166                invalidated |= push_invalidation(
1167                    invalidation,
1168                    d.invalidation_kind(),
1169                    descendant_invalidations,
1170                    sibling_invalidations,
1171                );
1172            }
1173            invalidated
1174        };
1175
1176        if invalidated_self {
1177            self.data.hint.insert(RestyleHint::RESTYLE_SELF);
1178        }
1179        invalidated_self
1180    }
1181
1182    fn should_process_descendants(&mut self, element: E) -> bool {
1183        if element == self.element {
1184            return should_process_descendants(self.data);
1185        }
1186
1187        match element.borrow_data() {
1188            Some(d) => should_process_descendants(&d),
1189            None => false,
1190        }
1191    }
1192
1193    fn recursion_limit_exceeded(&mut self, _element: E) {
1194        unreachable!("Unexpected recursion limit");
1195    }
1196
1197    fn invalidated_descendants(&mut self, element: E, child: E) {
1198        invalidated_descendants(element, child)
1199    }
1200
1201    fn invalidated_self(&mut self, element: E) {
1202        debug_assert_ne!(element, self.element);
1203        invalidated_self(element);
1204    }
1205
1206    fn invalidated_sibling(&mut self, element: E, of: E) {
1207        debug_assert_ne!(element, self.element);
1208        invalidated_sibling(element, of);
1209    }
1210}
1211
1212/// Invalidation for the selector(s) inside a relative selector.
1213pub struct RelativeSelectorInnerInvalidationProcessor<'a, 'b, 'c, E>
1214where
1215    E: TElement + 'a,
1216{
1217    /// Matching context to be used.
1218    matching_context: MatchingContext<'b, E::Impl>,
1219    /// Table of snapshots.
1220    snapshot_table: Option<&'c ServoElementSnapshotTable>,
1221    /// Incoming dependencies to be processed.
1222    dependencies: &'c ElementDependencies<'a>,
1223    /// Generated invalidations.
1224    invalidations: InnerInvalidations<'a, E>,
1225    /// Traversal map for this invalidation.
1226    traversal_map: &'b SiblingTraversalMap<E>,
1227}
1228
1229impl<'a, 'b, 'c, E> RelativeSelectorInnerInvalidationProcessor<'a, 'b, 'c, E>
1230where
1231    E: TElement + 'a,
1232{
1233    fn new(
1234        quirks_mode: QuirksMode,
1235        snapshot_table: Option<&'c ServoElementSnapshotTable>,
1236        dependencies: &'c ElementDependencies<'a>,
1237        selector_caches: &'b mut SelectorCaches,
1238        traversal_map: &'b SiblingTraversalMap<E>,
1239    ) -> Self {
1240        let matching_context = MatchingContext::new_for_visited(
1241            MatchingMode::Normal,
1242            None,
1243            selector_caches,
1244            VisitedHandlingMode::AllLinksVisitedAndUnvisited,
1245            quirks_mode,
1246            NeedsSelectorFlags::No,
1247            MatchingForInvalidation::Yes,
1248        );
1249        Self {
1250            matching_context,
1251            snapshot_table,
1252            dependencies,
1253            invalidations: InnerInvalidations::default(),
1254            traversal_map,
1255        }
1256    }
1257
1258    fn note_dependency(
1259        &mut self,
1260        element: E,
1261        host: Option<OpaqueElement>,
1262        dependency: &'a Dependency,
1263        descendant_invalidations: &mut DescendantInvalidationLists<'a>,
1264        sibling_invalidations: &mut InvalidationVector<'a>,
1265    ) {
1266        match dependency.invalidation_kind() {
1267            DependencyInvalidationKind::FullSelector => unreachable!(),
1268            DependencyInvalidationKind::Normal(_) | DependencyInvalidationKind::Scope(_) => (),
1269            DependencyInvalidationKind::Relative(kind) => {
1270                self.found_relative_selector_invalidation(element, kind, dependency);
1271                return;
1272            },
1273        }
1274        if matches!(
1275            dependency.normal_invalidation_kind(),
1276            NormalDependencyInvalidationKind::Element
1277        ) {
1278            // Ok, keep heading outwards.
1279            debug_assert!(
1280                dependency.next.is_some(),
1281                "Orphaned inner selector dependency?"
1282            );
1283            if let Some(next) = dependency.next.as_ref() {
1284                self.note_dependency(
1285                    element,
1286                    host,
1287                    &next.as_ref().slice()[0],
1288                    descendant_invalidations,
1289                    sibling_invalidations,
1290                );
1291            }
1292            return;
1293        }
1294        let invalidation = Invalidation::new(dependency, None, None);
1295        match dependency.normal_invalidation_kind() {
1296            NormalDependencyInvalidationKind::Descendants => {
1297                // Descendant invalidations are simplified due to pseudo-elements not being available within the relative selector.
1298                descendant_invalidations.dom_descendants.push(invalidation)
1299            },
1300            NormalDependencyInvalidationKind::Siblings => sibling_invalidations.push(invalidation),
1301            // Note(dshin, bug 1940212): Nesting can enabling stuffing pseudo-elements into :has, like `::marker { :has(&) }`.
1302            // Ideally, we can just not insert the dependency into the invalidation map, but the necessary selector information
1303            // for this (i.e. `HAS_PSEUDO`) is filtered out in `replace_parent_selector` through
1304            // `SelectorFlags::forbidden_for_nesting`, so just ignoring such dependencies here is the best we can do.
1305            _ => (),
1306        }
1307    }
1308
1309    /// Take the generated invalidations.
1310    fn take_invalidations(self) -> InnerInvalidations<'a, E> {
1311        self.invalidations
1312    }
1313}
1314
1315impl<'a, 'b, 'c, E> InvalidationProcessor<'a, 'b, E>
1316    for RelativeSelectorInnerInvalidationProcessor<'a, 'b, 'c, E>
1317where
1318    E: TElement + 'a,
1319{
1320    fn check_outer_dependency(
1321        &mut self,
1322        dependency: &Dependency,
1323        element: E,
1324        _: Option<OpaqueElement>,
1325    ) -> bool {
1326        if let Some(snapshot_table) = self.snapshot_table {
1327            let wrapper = ElementWrapper::new(element, snapshot_table);
1328            return check_dependency(
1329                dependency,
1330                &element,
1331                &wrapper,
1332                &mut self.matching_context,
1333                None,
1334            );
1335        }
1336        // Just invalidate if we don't have a snapshot.
1337        true
1338    }
1339
1340    fn matching_context(&mut self) -> &mut MatchingContext<'b, E::Impl> {
1341        &mut self.matching_context
1342    }
1343
1344    fn collect_invalidations(
1345        &mut self,
1346        element: E,
1347        _self_invalidations: &mut InvalidationVector<'a>,
1348        descendant_invalidations: &mut DescendantInvalidationLists<'a>,
1349        sibling_invalidations: &mut InvalidationVector<'a>,
1350    ) -> bool {
1351        for (scope, dependency) in self.dependencies {
1352            self.note_dependency(
1353                element,
1354                *scope,
1355                dependency,
1356                descendant_invalidations,
1357                sibling_invalidations,
1358            )
1359        }
1360        false
1361    }
1362
1363    fn should_process_descendants(&mut self, _element: E) -> bool {
1364        true
1365    }
1366
1367    fn recursion_limit_exceeded(&mut self, _element: E) {
1368        unreachable!("Unexpected recursion limit");
1369    }
1370
1371    // Don't do anything for normal invalidations.
1372    fn invalidated_self(&mut self, _element: E) {}
1373    fn invalidated_sibling(&mut self, _sibling: E, _of: E) {}
1374    fn invalidated_descendants(&mut self, _element: E, _child: E) {}
1375
1376    fn found_relative_selector_invalidation(
1377        &mut self,
1378        element: E,
1379        kind: RelativeDependencyInvalidationKind,
1380        dep: &'a Dependency,
1381    ) {
1382        debug_assert!(dep.next.is_some(), "Orphaned inners selector?");
1383        if element.relative_selector_search_direction().is_empty() {
1384            return;
1385        }
1386        self.invalidations.push((
1387            element,
1388            RelativeSelectorInvalidation {
1389                host: self.matching_context.current_host,
1390                kind,
1391                dependency: &dep.next.as_ref().unwrap().as_ref().slice()[0],
1392            },
1393        ));
1394    }
1395
1396    fn sibling_traversal_map(&self) -> &SiblingTraversalMap<E> {
1397        self.traversal_map
1398    }
1399}
style/invalidation/element/relative_selector.rs

style/invalidation/element/
relative_selector.rs
