ClassChangeInvalidation.cpp [plain text]
#include "config.h"
#include "ClassChangeInvalidation.h"
#include "DocumentRuleSets.h"
#include "ElementChildIterator.h"
#include "HTMLSlotElement.h"
#include "ShadowRoot.h"
#include "SpaceSplitString.h"
#include "StyleInvalidator.h"
#include "StyleResolver.h"
#include "StyleScope.h"
#include <wtf/BitVector.h>
namespace WebCore {
namespace Style {
using ClassChangeVector = Vector<AtomicStringImpl*, 4>;
static ClassChangeVector collectClasses(const SpaceSplitString& classes)
{
ClassChangeVector result;
result.reserveCapacity(classes.size());
for (unsigned i = 0; i < classes.size(); ++i)
result.uncheckedAppend(classes[i].impl());
return result;
}
static ClassChangeVector computeClassChange(const SpaceSplitString& oldClasses, const SpaceSplitString& newClasses)
{
unsigned oldSize = oldClasses.size();
unsigned newSize = newClasses.size();
if (!oldSize)
return collectClasses(newClasses);
if (!newSize)
return collectClasses(oldClasses);
ClassChangeVector changedClasses;
BitVector remainingClassBits;
remainingClassBits.ensureSize(oldSize);
for (unsigned i = 0; i < newSize; ++i) {
bool foundFromBoth = false;
for (unsigned j = 0; j < oldSize; ++j) {
if (newClasses[i] == oldClasses[j]) {
remainingClassBits.quickSet(j);
foundFromBoth = true;
}
}
if (foundFromBoth)
continue;
changedClasses.append(newClasses[i].impl());
}
for (unsigned i = 0; i < oldSize; ++i) {
if (remainingClassBits.quickGet(i))
continue;
changedClasses.append(oldClasses[i].impl());
}
return changedClasses;
}
static bool mayBeAffectedByHostRules(ShadowRoot* shadowRoot, AtomicStringImpl* changedClass, bool& mayAffectShadowTree)
{
if (!shadowRoot)
return false;
auto& shadowRuleSets = shadowRoot->styleScope().resolver().ruleSets();
auto& authorStyle = shadowRuleSets.authorStyle();
if (authorStyle.hostPseudoClassRules().isEmpty() && !authorStyle.hasHostPseudoClassRulesMatchingInShadowTree())
return false;
if (!shadowRuleSets.features().classesInRules.contains(changedClass))
return false;
if (authorStyle.hasHostPseudoClassRulesMatchingInShadowTree())
mayAffectShadowTree = true;
return true;
}
static bool mayBeAffectedBySlottedRules(const Vector<ShadowRoot*>& assignedShadowRoots, AtomicStringImpl* changedClass)
{
for (auto& assignedShadowRoot : assignedShadowRoots) {
auto& ruleSets = assignedShadowRoot->styleScope().resolver().ruleSets();
if (ruleSets.authorStyle().slottedPseudoElementRules().isEmpty())
continue;
if (ruleSets.features().classesInRules.contains(changedClass))
return true;
}
return false;
}
void ClassChangeInvalidation::invalidateStyle(const SpaceSplitString& oldClasses, const SpaceSplitString& newClasses)
{
auto changedClasses = computeClassChange(oldClasses, newClasses);
bool mayAffectShadowTree = false;
auto& ruleSets = m_element.styleResolver().ruleSets();
auto* shadowRoot = m_element.shadowRoot();
auto assignedShadowRoots = assignedShadowRootsIfSlotted(m_element);
ClassChangeVector changedClassesAffectingStyle;
for (auto* changedClass : changedClasses) {
bool mayAffectStyle = ruleSets.features().classesInRules.contains(changedClass)
|| mayBeAffectedByHostRules(shadowRoot, changedClass, mayAffectShadowTree)
|| mayBeAffectedBySlottedRules(assignedShadowRoots, changedClass);
if (mayAffectStyle)
changedClassesAffectingStyle.append(changedClass);
};
if (changedClassesAffectingStyle.isEmpty())
return;
if (shadowRoot && ruleSets.authorStyle().hasShadowPseudoElementRules())
mayAffectShadowTree = true;
if (is<HTMLSlotElement>(m_element) && !ruleSets.authorStyle().slottedPseudoElementRules().isEmpty())
mayAffectShadowTree = true;
if (mayAffectShadowTree) {
m_element.invalidateStyleForSubtree();
return;
}
m_element.invalidateStyle();
if (!childrenOfType<Element>(m_element).first())
return;
for (auto* changedClass : changedClassesAffectingStyle) {
auto* ancestorClassRules = ruleSets.ancestorClassRules(changedClass);
if (!ancestorClassRules)
continue;
m_descendantInvalidationRuleSets.append(ancestorClassRules);
}
}
void ClassChangeInvalidation::invalidateDescendantStyle()
{
for (auto* ancestorClassRules : m_descendantInvalidationRuleSets) {
Invalidator invalidator(*ancestorClassRules);
invalidator.invalidateStyle(m_element);
}
}
}
}