static void activateObserver(PassRefPtr<MutationObserver> observer)
{
if (activeMutationObservers().isEmpty())
Microtask::enqueueMicrotask(base::Bind(&MutationObserver::deliverMutations));
activeMutationObservers().add(observer);
}
void MutationObserver::notifyMutationObservers()
{
// https://dom.spec.whatwg.org/#notify-mutation-observers
// 1. Unset mutation observer compound microtask queued flag.
mutationObserverCompoundMicrotaskQueuedFlag = false;
ASSERT(isMainThread());
static bool deliveryInProgress = false;
if (deliveryInProgress)
return;
deliveryInProgress = true;
if (!suspendedMutationObservers().isEmpty()) {
Vector<RefPtr<MutationObserver>> suspended;
copyToVector(suspendedMutationObservers(), suspended);
for (auto& observer : suspended) {
if (!observer->canDeliver())
continue;
suspendedMutationObservers().remove(observer);
activeMutationObservers().add(observer);
}
}
while (!activeMutationObservers().isEmpty() || !signalSlotList().isEmpty()) {
// 2. Let notify list be a copy of unit of related similar-origin browsing contexts' list of MutationObserver objects.
Vector<RefPtr<MutationObserver>> notifyList;
copyToVector(activeMutationObservers(), notifyList);
activeMutationObservers().clear();
std::sort(notifyList.begin(), notifyList.end(), [](auto& lhs, auto& rhs) {
return lhs->m_priority < rhs->m_priority;
});
// 3. Let signalList be a copy of unit of related similar-origin browsing contexts' signal slot list.
// 4. Empty unit of related similar-origin browsing contexts' signal slot list.
Vector<RefPtr<HTMLSlotElement>> slotList;
if (!signalSlotList().isEmpty()) {
slotList.swap(signalSlotList());
for (auto& slot : slotList)
slot->didRemoveFromSignalSlotList();
}
// 5. For each MutationObserver object mo in notify list, execute a compound microtask subtask
for (auto& observer : notifyList) {
if (observer->canDeliver())
observer->deliver();
else
suspendedMutationObservers().add(observer);
}
// 6. For each slot slot in signalList, in order, fire an event named slotchange, with its bubbles attribute set to true, at slot.
for (auto& slot : slotList)
slot->dispatchSlotChangeEvent();
}
deliveryInProgress = false;
}
void MutationObserver::deliverMutations() {
DCHECK(isMainThread());
MutationObserverVector observers;
copyToVector(activeMutationObservers(), observers);
activeMutationObservers().clear();
std::sort(observers.begin(), observers.end(), ObserverLessThan());
for (size_t i = 0; i < observers.size(); ++i) {
if (observers[i]->shouldBeSuspended())
suspendedMutationObservers().add(observers[i]);
else
observers[i]->deliver();
}
}
void MutationObserver::setHasTransientRegistration()
{
ASSERT(isMainThread());
activeMutationObservers().add(this);
queueMutationObserverCompoundMicrotask();
}
void MutationObserver::enqueueMutationRecord(Ref<MutationRecord>&& mutation)
{
ASSERT(isMainThread());
m_records.append(WTFMove(mutation));
activeMutationObservers().add(this);
queueMutationObserverCompoundMicrotask();
}
static void activateObserver(MutationObserver* observer) {
if (activeMutationObservers().isEmpty())
Microtask::enqueueMicrotask(WTF::bind(&MutationObserver::deliverMutations));
activeMutationObservers().add(observer);
}
