invalidation_set.h | Explore in Territory

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#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_CSS_INVALIDATION_INVALIDATION_SET_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_CSS_INVALIDATION_INVALIDATION_SET_H_

#include <memory>

#include "base/memory/scoped_refptr.h"
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/core/css/invalidation/invalidation_flags.h"
#include "third_party/blink/renderer/platform/wtf/allocator/allocator.h"
#include "third_party/blink/renderer/platform/wtf/casting.h"
#include "third_party/blink/renderer/platform/wtf/forward.h"
#include "third_party/blink/renderer/platform/wtf/hash_set.h"
#include "third_party/blink/renderer/platform/wtf/text/atomic_string_hash.h"
#include "third_party/blink/renderer/platform/wtf/text/string_hash.h"

namespace blink {

class Element;
class TracedValue;

enum class InvalidationType { … };

class InvalidationSet;

struct CORE_EXPORT InvalidationSetDeleter { … };

// Tracks data to determine which descendants in a DOM subtree, or
// siblings and their descendants, need to have style recalculated.
//
// Some example invalidation sets:
//
// .z {}
//   For class z we will have a DescendantInvalidationSet with invalidatesSelf
//   (the element itself is invalidated).
//
// .y .z {}
//   For class y we will have a DescendantInvalidationSet containing class z.
//
// .x ~ .z {}
//   For class x we will have a SiblingInvalidationSet containing class z, with
//   invalidatesSelf (the sibling itself is invalidated).
//
// .w ~ .y .z {}
//   For class w we will have a SiblingInvalidationSet containing class y, with
//   the SiblingInvalidationSet havings siblingDescendants containing class z.
//
// .v * {}
//   For class v we will have a DescendantInvalidationSet with
//   wholeSubtreeInvalid.
//
// .u ~ * {}
//   For class u we will have a SiblingInvalidationSet with wholeSubtreeInvalid
//   and invalidatesSelf (for all siblings, the sibling itself is invalidated).
//
// .t .v, .t ~ .z {}
//   For class t we will have a SiblingInvalidationSet containing class z, with
//   the SiblingInvalidationSet also holding descendants containing class v.
//
// We avoid virtual functions to minimize space consumption.
class CORE_EXPORT InvalidationSet
    : public WTF::RefCounted<InvalidationSet, InvalidationSetDeleter> { … };

class CORE_EXPORT DescendantInvalidationSet final : public InvalidationSet { … };

class CORE_EXPORT SiblingInvalidationSet : public InvalidationSet { … };

// For invalidation of :nth-* selectors on dom mutations we use a sibling
// invalidation set which is scheduled on the parent node of the DOM mutation
// affected by the :nth-* selectors.
//
// During invalidation, the set is pushed into the SiblingData used for
// invalidating the direct children.
//
// Features are collected into this set as if the selectors were preceded by a
// universal selector with an indirect adjacent combinator.
//
// Example: If you have the following selector:
//
// :nth-of-type(2n+1) .x {}
//
// we need to invalidate descendants of class 'x' of an arbitrary number of
// siblings when one of the siblings are added or removed. We then collect
// features to the NthSiblingInvalidationSet as if we had a selector:
//
// * ~ :nth-of-type(2n+1) .x {}
//
// Pushing that set into SiblingData before invalidating the siblings will then
// invalidate descendants with class 'x'.

class NthSiblingInvalidationSet final : public SiblingInvalidationSet { … };

InvalidationSetVector;

struct InvalidationLists { … };

template <typename InvalidationSet::BackingType type>
void InvalidationSet::Backing<type>::Add(InvalidationSet::BackingFlags& flags,
                                         const AtomicString& string) { … }

template <typename InvalidationSet::BackingType type>
void InvalidationSet::Backing<type>::Clear(
    InvalidationSet::BackingFlags& flags) { … }

template <typename InvalidationSet::BackingType type>
bool InvalidationSet::Backing<type>::Contains(
    const InvalidationSet::BackingFlags& flags,
    const AtomicString& string) const { … }

template <typename InvalidationSet::BackingType type>
bool InvalidationSet::Backing<type>::IsEmpty(
    const InvalidationSet::BackingFlags& flags) const { … }

template <typename InvalidationSet::BackingType type>
size_t InvalidationSet::Backing<type>::Size(
    const InvalidationSet::BackingFlags& flags) const { … }

template <>
struct DowncastTraits<DescendantInvalidationSet> { … };

template <>
struct DowncastTraits<SiblingInvalidationSet> { … };

template <>
struct DowncastTraits<NthSiblingInvalidationSet> { … };

CORE_EXPORT std::ostream& operator<<(std::ostream&, const InvalidationSet&);

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_CSS_INVALIDATION_INVALIDATION_SET_H_
chromium/third_party/blink/renderer/core/css/invalidation/invalidation_set.h
