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,
34    IncludeStartingStyle, MatchingContext, MatchingForInvalidation, MatchingMode,
35    NeedsSelectorFlags, QuirksMode, SelectorCaches, 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 mut iter = dependency.selector.iter_from(dependency.selector_offset);
128            while let Some(c) = iter.next() {
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().map_or(false, |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_n = &a_deps.as_ref().slice()[0];
388        let b_n = &b_deps.as_ref().slice()[0];
389        if SelectorKey::new(&a_n.selector) != SelectorKey::new(&b_n.selector) {
390            return false;
391        }
392        a_next = a_n.next.as_ref();
393        b_next = b_n.next.as_ref();
394    }
395    if a_next.is_some() || b_next.is_some() {
396        return false;
397    }
398
399    // Ok, now, do the compounds actually match?
400    // This can get expensive quickly, but we're assuming that:
401    //
402    //   * In most cases, authors don't generally duplicate compounds in a selector, so
403    //     this fails quickly
404    //   * In cases where compounds are duplicated, reducing the number of invalidations
405    //     has a payoff that offsets the comparison cost
406    //
407    // Note, `.a.b` != `.b.a` - doesn't affect correctness, though.
408    // TODO(dshin): Caching this may be worth it as well?
409    let mut a_iter = a.selector.iter_from(a.selector_offset);
410    let mut b_iter = b.selector.iter_from(b.selector_offset);
411    loop {
412        let a_component = a_iter.next();
413        let b_component = b_iter.next();
414
415        if a_component != b_component {
416            return false;
417        }
418        let Some(component) = a_component else {
419            return true;
420        };
421        if !allow_indexed_selectors && component.has_indexed_selector_in_subject() {
422            // The element's positioning matters, so can't collapse.
423            return false;
424        }
425    }
426}
427
428impl<'a, E> RelativeSelectorDependencyCollector<'a, E>
429where
430    E: TElement,
431{
432    fn new(top: E, optimization_context: Option<OptimizationContext<'a, E>>) -> Self {
433        Self {
434            dependencies: FxHashMap::default(),
435            invalidations: AlreadyInvalidated::default(),
436            top,
437            optimization_context,
438        }
439    }
440
441    fn insert_invalidation(
442        &mut self,
443        element: E,
444        dependency: &'a Dependency,
445        host: Option<OpaqueElement>,
446    ) {
447        let in_subtree = element != self.top;
448        if let Some(entry) = self.invalidations.iter_mut().find(|entry| {
449            // If we're in the subtree of DOM manipulation - worrying the about positioning of this element
450            // is irrelevant, because the DOM structure is either completely new or about to go away.
451            let both_in_subtree = in_subtree && entry.element != self.top;
452            // If we're considering the same element for invalidation, their evaluation of the indexed selector
453            // is identical by definition.
454            let same_element = element == entry.element;
455            invalidation_can_collapse(
456                dependency,
457                entry.dependency,
458                both_in_subtree || same_element,
459            )
460        }) {
461            entry.update(element, host, dependency)
462        } else {
463            self.invalidations
464                .push(AlreadyInvalidatedEntry::new(element, host, dependency));
465        }
466    }
467
468    /// Add this dependency, if it is unique (i.e. Different outer dependency or same outer dependency
469    /// but requires a different invalidation traversal).
470    pub fn add_dependency(
471        &mut self,
472        dependency: &'a Dependency,
473        element: E,
474        host: Option<OpaqueElement>,
475    ) {
476        match dependency.invalidation_kind() {
477            DependencyInvalidationKind::FullSelector => unreachable!(),
478            DependencyInvalidationKind::Normal(..) | DependencyInvalidationKind::Scope(..) => {
479                self.dependencies
480                    .entry(element)
481                    .and_modify(|v| v.push((host, dependency)))
482                    .or_default()
483                    .push((host, dependency));
484            },
485            DependencyInvalidationKind::Relative(kind) => {
486                debug_assert!(
487                    dependency.next.is_some(),
488                    "Orphaned inner relative selector?"
489                );
490                if element != self.top
491                    && matches!(
492                        kind,
493                        RelativeDependencyInvalidationKind::Parent
494                            | RelativeDependencyInvalidationKind::PrevSibling
495                            | RelativeDependencyInvalidationKind::EarlierSibling
496                    )
497                {
498                    return;
499                }
500                if early_reject_by_local_name(
501                    &dependency.selector,
502                    dependency.selector_offset,
503                    &element,
504                ) {
505                    return;
506                }
507                self.insert_invalidation(element, dependency, host);
508            },
509        };
510    }
511
512    /// Get the dependencies in a list format.
513    fn get(self) -> ToInvalidate<'a, E> {
514        let mut result = ToInvalidate::default();
515        for invalidation in self.invalidations {
516            match invalidation.dependency.invalidation_kind() {
517                DependencyInvalidationKind::FullSelector => unreachable!(),
518                DependencyInvalidationKind::Normal(_) | DependencyInvalidationKind::Scope(_) => {
519                    unreachable!("Inner selector in invalidation?")
520                },
521                DependencyInvalidationKind::Relative(kind) => {
522                    if let Some(context) = self.optimization_context.as_ref() {
523                        if context.can_be_ignored(
524                            invalidation.element != self.top,
525                            invalidation.element,
526                            invalidation.host,
527                            invalidation.dependency,
528                            invalidation.leftmost_collapse_offset,
529                        ) {
530                            continue;
531                        }
532                    }
533                    let dependency = &invalidation.dependency.next.as_ref().unwrap().slice()[0];
534                    result.invalidations.push(RelativeSelectorInvalidation {
535                        kind,
536                        host: invalidation.host,
537                        dependency,
538                    });
539                    // We move the invalidation up to the top of the subtree to avoid unnecessary traveral, but
540                    // this means that we need to take ancestor-earlier sibling invalidations into account, as
541                    // they'd look into earlier siblings of the top of the subtree as well.
542                    if invalidation.element != self.top
543                        && matches!(
544                            kind,
545                            RelativeDependencyInvalidationKind::AncestorEarlierSibling
546                                | RelativeDependencyInvalidationKind::AncestorPrevSibling
547                        )
548                    {
549                        result.invalidations.push(RelativeSelectorInvalidation {
550                            kind: if matches!(
551                                kind,
552                                RelativeDependencyInvalidationKind::AncestorPrevSibling
553                            ) {
554                                RelativeDependencyInvalidationKind::PrevSibling
555                            } else {
556                                RelativeDependencyInvalidationKind::EarlierSibling
557                            },
558                            host: invalidation.host,
559                            dependency,
560                        });
561                    }
562                },
563            };
564        }
565        for (key, element_dependencies) in self.dependencies {
566            // At least for now, we don't try to optimize away dependencies emitted from nested selectors.
567            result.dependencies.push((key, element_dependencies));
568        }
569        result
570    }
571
572    fn collect_all_dependencies_for_element(
573        &mut self,
574        element: E,
575        scope: Option<OpaqueElement>,
576        quirks_mode: QuirksMode,
577        map: &'a InvalidationMap,
578        additional_relative_selector_invalidation_map: &'a AdditionalRelativeSelectorInvalidationMap,
579        operation: DomMutationOperation,
580    ) {
581        element
582            .id()
583            .map(|v| match map.id_to_selector.get(v, quirks_mode) {
584                Some(v) => {
585                    for dependency in v {
586                        if !operation.accept(dependency, element) {
587                            continue;
588                        }
589                        self.add_dependency(dependency, element, scope);
590                    }
591                },
592                None => (),
593            });
594        element.each_class(|v| match map.class_to_selector.get(v, quirks_mode) {
595            Some(v) => {
596                for dependency in v {
597                    if !operation.accept(dependency, element) {
598                        continue;
599                    }
600                    self.add_dependency(dependency, element, scope);
601                }
602            },
603            None => (),
604        });
605        element.each_custom_state(|v| match map.custom_state_affecting_selectors.get(v) {
606            Some(v) => {
607                for dependency in v {
608                    if !operation.accept(dependency, element) {
609                        continue;
610                    }
611                    self.add_dependency(dependency, element, scope);
612                }
613            },
614            None => (),
615        });
616        element.each_attr_name(|v| match map.other_attribute_affecting_selectors.get(v) {
617            Some(v) => {
618                for dependency in v {
619                    if !operation.accept(dependency, element) {
620                        continue;
621                    }
622                    self.add_dependency(dependency, element, scope);
623                }
624            },
625            None => (),
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            IncludeStartingStyle::No,
990            self.quirks_mode,
991            NeedsSelectorFlags::No,
992            MatchingForInvalidation::Yes,
993        );
994        let mut data = match element.mutate_data() {
995            Some(data) => data,
996            None => return,
997        };
998        let mut processor = RelativeSelectorOuterInvalidationProcessor {
999            element,
1000            host,
1001            data: data.deref_mut(),
1002            dependency: &*outer_dependency,
1003            matching_context,
1004            traversal_map: &self.sibling_traversal_map,
1005        };
1006        let result = TreeStyleInvalidator::new(element, None, &mut processor).invalidate();
1007        (self.invalidated)(element, &result);
1008    }
1009
1010    /// Does this relative selector dependency have its relative selector in the subject position?
1011    fn is_subject(outer_dependency: &Dependency) -> bool {
1012        debug_assert!(
1013            matches!(
1014                outer_dependency.invalidation_kind(),
1015                DependencyInvalidationKind::Normal(_) | DependencyInvalidationKind::Scope(_)
1016            ),
1017            "Outer selector of relative selector is relative?"
1018        );
1019
1020        if let Some(x) = outer_dependency.next.as_ref() {
1021            // We only care to ensure that we're the subject in the outermost selector of the current
1022            // selector - Crossing over a scope invalidation would mean moving into a selector inside
1023            // the current scope block
1024            if matches!(
1025                outer_dependency.invalidation_kind(),
1026                DependencyInvalidationKind::Normal(..)
1027            ) {
1028                if !Self::is_subject(&x.as_ref().slice()[0]) {
1029                    // Not subject in outer selector.
1030                    return false;
1031                }
1032            }
1033        }
1034        outer_dependency
1035            .selector
1036            .is_rightmost(outer_dependency.selector_offset)
1037    }
1038}
1039
1040/// Blindly invalidate everything outside of a relative selector.
1041/// Consider `:is(.a :has(.b) .c ~ .d) ~ .e .f`, where .b gets deleted.
1042/// Since the tree mutated, we cannot rely on snapshots.
1043pub struct RelativeSelectorOuterInvalidationProcessor<'a, 'b, E: TElement> {
1044    /// Element being invalidated.
1045    pub element: E,
1046    /// The current shadow host, if any.
1047    pub host: Option<OpaqueElement>,
1048    /// Data for the element being invalidated.
1049    pub data: &'a mut ElementData,
1050    /// Dependency to be processed.
1051    pub dependency: &'b Dependency,
1052    /// Matching context to use for invalidation.
1053    pub matching_context: MatchingContext<'a, E::Impl>,
1054    /// Traversal map for this invalidation.
1055    pub traversal_map: &'a SiblingTraversalMap<E>,
1056}
1057
1058impl<'a, 'b: 'a, E: 'a> InvalidationProcessor<'b, 'a, E>
1059    for RelativeSelectorOuterInvalidationProcessor<'a, 'b, E>
1060where
1061    E: TElement,
1062{
1063    fn invalidates_on_pseudo_element(&self) -> bool {
1064        true
1065    }
1066
1067    fn check_outer_dependency(
1068        &mut self,
1069        _dependency: &Dependency,
1070        _element: E,
1071        _: Option<OpaqueElement>,
1072    ) -> bool {
1073        // At this point, we know a relative selector invalidated, and are ignoring them.
1074        true
1075    }
1076
1077    fn matching_context(&mut self) -> &mut MatchingContext<'a, E::Impl> {
1078        &mut self.matching_context
1079    }
1080
1081    fn sibling_traversal_map(&self) -> &SiblingTraversalMap<E> {
1082        self.traversal_map
1083    }
1084
1085    fn collect_invalidations(
1086        &mut self,
1087        element: E,
1088        _self_invalidations: &mut InvalidationVector<'b>,
1089        descendant_invalidations: &mut DescendantInvalidationLists<'b>,
1090        sibling_invalidations: &mut InvalidationVector<'b>,
1091    ) -> bool {
1092        debug_assert_eq!(element, self.element);
1093        debug_assert!(
1094            self.matching_context.matching_for_invalidation(),
1095            "Not matching for invalidation?"
1096        );
1097
1098        // Ok, this element can potentially an anchor to the given dependency.
1099        // Before we do the potentially-costly ancestor/earlier sibling traversal,
1100        // See if it can actuall be an anchor by trying to match the "rest" of the selector
1101        // outside and to the left of `:has` in question.
1102        // e.g. Element under consideration can only be the anchor to `:has` in
1103        // `.foo .bar ~ .baz:has()`, iff it matches `.foo .bar ~ .baz`.
1104        let invalidated_self = {
1105            let mut invalidated = false;
1106            let mut dependencies_to_invalidate: SmallVec<[&Dependency; 1]> =
1107                smallvec![self.dependency];
1108            while let Some(d) = dependencies_to_invalidate.pop() {
1109                debug_assert!(
1110                    matches!(
1111                        d.invalidation_kind(),
1112                        DependencyInvalidationKind::Normal(_)
1113                            | DependencyInvalidationKind::Scope(_)
1114                    ),
1115                    "Unexpected dependency kind"
1116                );
1117                if !dependency_may_be_relevant(d, &element, false) {
1118                    continue;
1119                }
1120                if !matches_selector(
1121                    &d.selector,
1122                    d.selector_offset,
1123                    None,
1124                    &element,
1125                    self.matching_context(),
1126                ) {
1127                    continue;
1128                }
1129
1130                let invalidation_kind = d.invalidation_kind();
1131
1132                if let DependencyInvalidationKind::Scope(scope_kind) = invalidation_kind {
1133                    if d.selector.is_rightmost(d.selector_offset) {
1134                        if scope_kind == ScopeDependencyInvalidationKind::ScopeEnd {
1135                            let invalidations = note_scope_dependency_force_at_subject(
1136                                d,
1137                                self.matching_context.current_host.clone(),
1138                                self.matching_context.scope_element,
1139                                false,
1140                            );
1141                            descendant_invalidations
1142                                .dom_descendants
1143                                .extend(invalidations);
1144
1145                            invalidated |= true;
1146                        } else if let Some(ref next) = d.next {
1147                            dependencies_to_invalidate.extend(next.as_ref().slice());
1148                        }
1149                        continue;
1150                    }
1151                }
1152
1153                if matches!(
1154                    invalidation_kind,
1155                    DependencyInvalidationKind::Normal(NormalDependencyInvalidationKind::Element)
1156                ) {
1157                    if let Some(ref deps) = d.next {
1158                        // Normal dependencies should only have one next
1159                        dependencies_to_invalidate.push(&deps.as_ref().slice()[0]);
1160                        continue;
1161                    }
1162                    invalidated |= true;
1163                    continue;
1164                }
1165                debug_assert_ne!(d.selector_offset, 0);
1166                debug_assert_ne!(d.selector_offset, d.selector.len());
1167                let invalidation = Invalidation::new(&d, self.host, None);
1168                invalidated |= push_invalidation(
1169                    invalidation,
1170                    d.invalidation_kind(),
1171                    descendant_invalidations,
1172                    sibling_invalidations,
1173                );
1174            }
1175            invalidated
1176        };
1177
1178        if invalidated_self {
1179            self.data.hint.insert(RestyleHint::RESTYLE_SELF);
1180        }
1181        invalidated_self
1182    }
1183
1184    fn should_process_descendants(&mut self, element: E) -> bool {
1185        if element == self.element {
1186            return should_process_descendants(&self.data);
1187        }
1188
1189        match element.borrow_data() {
1190            Some(d) => should_process_descendants(&d),
1191            None => return false,
1192        }
1193    }
1194
1195    fn recursion_limit_exceeded(&mut self, _element: E) {
1196        unreachable!("Unexpected recursion limit");
1197    }
1198
1199    fn invalidated_descendants(&mut self, element: E, child: E) {
1200        invalidated_descendants(element, child)
1201    }
1202
1203    fn invalidated_self(&mut self, element: E) {
1204        debug_assert_ne!(element, self.element);
1205        invalidated_self(element);
1206    }
1207
1208    fn invalidated_sibling(&mut self, element: E, of: E) {
1209        debug_assert_ne!(element, self.element);
1210        invalidated_sibling(element, of);
1211    }
1212}
1213
1214/// Invalidation for the selector(s) inside a relative selector.
1215pub struct RelativeSelectorInnerInvalidationProcessor<'a, 'b, 'c, E>
1216where
1217    E: TElement + 'a,
1218{
1219    /// Matching context to be used.
1220    matching_context: MatchingContext<'b, E::Impl>,
1221    /// Table of snapshots.
1222    snapshot_table: Option<&'c ServoElementSnapshotTable>,
1223    /// Incoming dependencies to be processed.
1224    dependencies: &'c ElementDependencies<'a>,
1225    /// Generated invalidations.
1226    invalidations: InnerInvalidations<'a, E>,
1227    /// Traversal map for this invalidation.
1228    traversal_map: &'b SiblingTraversalMap<E>,
1229}
1230
1231impl<'a, 'b, 'c, E> RelativeSelectorInnerInvalidationProcessor<'a, 'b, 'c, E>
1232where
1233    E: TElement + 'a,
1234{
1235    fn new(
1236        quirks_mode: QuirksMode,
1237        snapshot_table: Option<&'c ServoElementSnapshotTable>,
1238        dependencies: &'c ElementDependencies<'a>,
1239        selector_caches: &'b mut SelectorCaches,
1240        traversal_map: &'b SiblingTraversalMap<E>,
1241    ) -> Self {
1242        let matching_context = MatchingContext::new_for_visited(
1243            MatchingMode::Normal,
1244            None,
1245            selector_caches,
1246            VisitedHandlingMode::AllLinksVisitedAndUnvisited,
1247            IncludeStartingStyle::No,
1248            quirks_mode,
1249            NeedsSelectorFlags::No,
1250            MatchingForInvalidation::Yes,
1251        );
1252        Self {
1253            matching_context,
1254            snapshot_table,
1255            dependencies,
1256            invalidations: InnerInvalidations::default(),
1257            traversal_map,
1258        }
1259    }
1260
1261    fn note_dependency(
1262        &mut self,
1263        element: E,
1264        host: Option<OpaqueElement>,
1265        dependency: &'a Dependency,
1266        descendant_invalidations: &mut DescendantInvalidationLists<'a>,
1267        sibling_invalidations: &mut InvalidationVector<'a>,
1268    ) {
1269        match dependency.invalidation_kind() {
1270            DependencyInvalidationKind::FullSelector => unreachable!(),
1271            DependencyInvalidationKind::Normal(_) | DependencyInvalidationKind::Scope(_) => (),
1272            DependencyInvalidationKind::Relative(kind) => {
1273                self.found_relative_selector_invalidation(element, kind, dependency);
1274                return;
1275            },
1276        }
1277        if matches!(
1278            dependency.normal_invalidation_kind(),
1279            NormalDependencyInvalidationKind::Element
1280        ) {
1281            // Ok, keep heading outwards.
1282            debug_assert!(
1283                dependency.next.is_some(),
1284                "Orphaned inner selector dependency?"
1285            );
1286            if let Some(next) = dependency.next.as_ref() {
1287                self.note_dependency(
1288                    element,
1289                    host,
1290                    &next.as_ref().slice()[0],
1291                    descendant_invalidations,
1292                    sibling_invalidations,
1293                );
1294            }
1295            return;
1296        }
1297        let invalidation = Invalidation::new(&dependency, None, None);
1298        match dependency.normal_invalidation_kind() {
1299            NormalDependencyInvalidationKind::Descendants => {
1300                // Descendant invalidations are simplified due to pseudo-elements not being available within the relative selector.
1301                descendant_invalidations.dom_descendants.push(invalidation)
1302            },
1303            NormalDependencyInvalidationKind::Siblings => sibling_invalidations.push(invalidation),
1304            // Note(dshin, bug 1940212): Nesting can enabling stuffing pseudo-elements into :has, like `::marker { :has(&) }`.
1305            // Ideally, we can just not insert the dependency into the invalidation map, but the necessary selector information
1306            // for this (i.e. `HAS_PSEUDO`) is filtered out in `replace_parent_selector` through
1307            // `SelectorFlags::forbidden_for_nesting`, so just ignoring such dependencies here is the best we can do.
1308            _ => (),
1309        }
1310    }
1311
1312    /// Take the generated invalidations.
1313    fn take_invalidations(self) -> InnerInvalidations<'a, E> {
1314        self.invalidations
1315    }
1316}
1317
1318impl<'a, 'b, 'c, E> InvalidationProcessor<'a, 'b, E>
1319    for RelativeSelectorInnerInvalidationProcessor<'a, 'b, 'c, E>
1320where
1321    E: TElement + 'a,
1322{
1323    fn check_outer_dependency(
1324        &mut self,
1325        dependency: &Dependency,
1326        element: E,
1327        _: Option<OpaqueElement>,
1328    ) -> bool {
1329        if let Some(snapshot_table) = self.snapshot_table {
1330            let wrapper = ElementWrapper::new(element, snapshot_table);
1331            return check_dependency(
1332                dependency,
1333                &element,
1334                &wrapper,
1335                &mut self.matching_context,
1336                None,
1337            );
1338        }
1339        // Just invalidate if we don't have a snapshot.
1340        true
1341    }
1342
1343    fn matching_context(&mut self) -> &mut MatchingContext<'b, E::Impl> {
1344        return &mut self.matching_context;
1345    }
1346
1347    fn collect_invalidations(
1348        &mut self,
1349        element: E,
1350        _self_invalidations: &mut InvalidationVector<'a>,
1351        descendant_invalidations: &mut DescendantInvalidationLists<'a>,
1352        sibling_invalidations: &mut InvalidationVector<'a>,
1353    ) -> bool {
1354        for (scope, dependency) in self.dependencies {
1355            self.note_dependency(
1356                element,
1357                *scope,
1358                dependency,
1359                descendant_invalidations,
1360                sibling_invalidations,
1361            )
1362        }
1363        false
1364    }
1365
1366    fn should_process_descendants(&mut self, _element: E) -> bool {
1367        true
1368    }
1369
1370    fn recursion_limit_exceeded(&mut self, _element: E) {
1371        unreachable!("Unexpected recursion limit");
1372    }
1373
1374    // Don't do anything for normal invalidations.
1375    fn invalidated_self(&mut self, _element: E) {}
1376    fn invalidated_sibling(&mut self, _sibling: E, _of: E) {}
1377    fn invalidated_descendants(&mut self, _element: E, _child: E) {}
1378
1379    fn found_relative_selector_invalidation(
1380        &mut self,
1381        element: E,
1382        kind: RelativeDependencyInvalidationKind,
1383        dep: &'a Dependency,
1384    ) {
1385        debug_assert!(dep.next.is_some(), "Orphaned inners selector?");
1386        if element.relative_selector_search_direction().is_empty() {
1387            return;
1388        }
1389        self.invalidations.push((
1390            element,
1391            RelativeSelectorInvalidation {
1392                host: self.matching_context.current_host,
1393                kind,
1394                dependency: &dep.next.as_ref().unwrap().as_ref().slice()[0],
1395            },
1396        ));
1397    }
1398
1399    fn sibling_traversal_map(&self) -> &SiblingTraversalMap<E> {
1400        &self.traversal_map
1401    }
1402}
style/invalidation/element/relative_selector.rs

style/invalidation/element/
relative_selector.rs
