Quellcode-Bibliothek AbstractRange.cpp Sprache: C

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/dom/AbstractRange.h"
#include "mozilla/dom/AbstractRangeBinding.h"
#include "mozilla/dom/ShadowIncludingTreeIterator.h"

#include "mozilla/Assertions.h"
#include "mozilla/Attributes.h"
#include "mozilla/RangeUtils.h"
#include "mozilla/dom/ChildIterator.h"
#include "mozilla/dom/Document.h"
#include "mozilla/dom/StaticRange.h"
#include "mozilla/dom/Selection.h"
#include "mozilla/dom/CrossShadowBoundaryRange.h"
#include "nsContentUtils.h"
#include "nsCycleCollectionParticipant.h"
#include "nsGkAtoms.h"
#include "nsINode.h"
#include "nsRange.h"
#include "nsTArray.h"

namespace mozilla::dom {

template nsresult AbstractRange::SetStartAndEndInternal(
    const RangeBoundary& aStartBoundary, const RangeBoundary& aEndBoundary,
    nsRange* aRange);
template nsresult AbstractRange::SetStartAndEndInternal(
    const RangeBoundary& aStartBoundary, const RawRangeBoundary& aEndBoundary,
    nsRange* aRange);
template nsresult AbstractRange::SetStartAndEndInternal(
    const RawRangeBoundary& aStartBoundary, const RangeBoundary& aEndBoundary,
    nsRange* aRange);
template nsresult AbstractRange::SetStartAndEndInternal(
    const RawRangeBoundary& aStartBoundary,
    const RawRangeBoundary& aEndBoundary, nsRange* aRange);
template nsresult AbstractRange::SetStartAndEndInternal(
    const RangeBoundary& aStartBoundary, const RangeBoundary& aEndBoundary,
    StaticRange* aRange);
template nsresult AbstractRange::SetStartAndEndInternal(
    const RangeBoundary& aStartBoundary, const RawRangeBoundary& aEndBoundary,
    StaticRange* aRange);
template nsresult AbstractRange::SetStartAndEndInternal(
    const RawRangeBoundary& aStartBoundary, const RangeBoundary& aEndBoundary,
    StaticRange* aRange);
template nsresult AbstractRange::SetStartAndEndInternal(
    const RawRangeBoundary& aStartBoundary,
    const RawRangeBoundary& aEndBoundary, StaticRange* aRange);
template bool AbstractRange::MaybeCacheToReuse(nsRange& aInstance);
template bool AbstractRange::MaybeCacheToReuse(StaticRange& aInstance);
template bool AbstractRange::MaybeCacheToReuse(
    CrossShadowBoundaryRange& aInstance);

bool AbstractRange::sHasShutDown = false;

NS_IMPL_CYCLE_COLLECTING_ADDREF(AbstractRange)
NS_IMPL_CYCLE_COLLECTING_RELEASE(AbstractRange)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(AbstractRange)
  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(AbstractRange)

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(AbstractRange)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mOwner);
  // mStart and mEnd may depend on or be depended on some other members in
  // concrete classes so that they should be unlinked in sub classes.
  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
  tmp->mSelections.Clear();
  // Unregistering of the common inclusive ancestors would by design
  // also happen when the actual implementations unlink `mStart`/`mEnd`.
  // This may introduce additional overhead which is not needed when unlinking,
  // therefore this is done here beforehand.
  if (tmp->mRegisteredClosestCommonInclusiveAncestor) {
    tmp->UnregisterClosestCommonInclusiveAncestor(true);
  }
  MOZ_DIAGNOSTIC_ASSERT(!tmp->isInList(),
                        "Shouldn't be registered now that we're unlinking");

NS_IMPL_CYCLE_COLLECTION_UNLINK_END

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(AbstractRange)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mOwner)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mStart)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mEnd)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mRegisteredClosestCommonInclusiveAncestor)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

// When aMarkDesendants is true, Set
// DescendantOfClosestCommonInclusiveAncestorForRangeInSelection flag for the
// shadow including children of aNode. When aMarkDesendants is false, unset that
// flag for the shadow including children of aNode.
void UpdateDescendantsByShadowIncludingOrder(const nsIContent& aNode,
                                             bool aMarkDesendants) {
  ShadowIncludingTreeIterator iter(*const_cast<nsIContent*>(&aNode));
  ++iter;  // We don't want to mark the root node

  while (iter) {
    nsINode* node = *iter;
    if (aMarkDesendants) {
      node->SetDescendantOfClosestCommonInclusiveAncestorForRangeInSelection();
    } else {
      node->ClearDescendantOfClosestCommonInclusiveAncestorForRangeInSelection();
    }

    if (node->IsClosestCommonInclusiveAncestorForRangeInSelection()) {
      iter.SkipChildren();
      continue;
    }
    ++iter;
  }
}

void AbstractRange::MarkDescendants(const nsINode& aNode) {
  // Set NodeIsDescendantOfClosestCommonInclusiveAncestorForRangeInSelection on
  // aNode's descendants unless aNode is already marked as a range common
  // ancestor or a descendant of one, in which case all of our descendants have
  // the bit set already.
  if (!aNode.IsMaybeSelected()) {
    // If aNode has a web-exposed shadow root, use this shadow tree and ignore
    // the children of aNode.
    if (aNode.GetShadowRootForSelection()) {
      UpdateDescendantsByShadowIncludingOrder(*aNode.AsContent(), true);
      return;
    }
    // don't set the Descendant bit on |aNode| itself
    nsINode* node = aNode.GetNextNode(&aNode);
    while (node) {
      node->SetDescendantOfClosestCommonInclusiveAncestorForRangeInSelection();
      if (!node->IsClosestCommonInclusiveAncestorForRangeInSelection()) {
        if (StaticPrefs::dom_shadowdom_selection_across_boundary_enabled()) {
          UpdateDescendantsByShadowIncludingOrder(*node->AsContent(), true);
          // sub-tree of node has been marked already
          node = node->GetNextNonChildNode(&aNode);
        } else {
          node = node->GetNextNode(&aNode);
        }
      } else {
        // optimize: skip this sub-tree since it's marked already.
        node = node->GetNextNonChildNode(&aNode);
      }
    }
  }
}

void AbstractRange::UnmarkDescendants(const nsINode& aNode) {
  // Unset NodeIsDescendantOfClosestCommonInclusiveAncestorForRangeInSelection
  // on aNode's descendants unless aNode is a descendant of another range common
  // ancestor. Also, exclude descendants of range common ancestors (but not the
  // common ancestor itself).
  if (!aNode
           .IsDescendantOfClosestCommonInclusiveAncestorForRangeInSelection()) {
    // If aNode has a web-exposed shadow root, use this shadow tree and ignore
    // the children of aNode.
    if (aNode.GetShadowRootForSelection()) {
      UpdateDescendantsByShadowIncludingOrder(*aNode.AsContent(), false);
      return;
    }
    // we know |aNode| doesn't have any bit set
    nsINode* node = aNode.GetNextNode(&aNode);
    while (node) {
      node->ClearDescendantOfClosestCommonInclusiveAncestorForRangeInSelection();
      if (!node->IsClosestCommonInclusiveAncestorForRangeInSelection()) {
        if (StaticPrefs::dom_shadowdom_selection_across_boundary_enabled()) {
          UpdateDescendantsByShadowIncludingOrder(*node->AsContent(), false);
          // sub-tree has been marked already
          node = node->GetNextNonChildNode(&aNode);
        } else {
          node = node->GetNextNode(&aNode);
        }
      } else {
        // We found an ancestor of an overlapping range, skip its descendants.
        node = node->GetNextNonChildNode(&aNode);
      }
    }
  }
}

// NOTE: If you need to change default value of members of AbstractRange,
//       update nsRange::Create(nsINode* aNode) and ClearForReuse() too.
AbstractRange::AbstractRange(nsINode* aNode, bool aIsDynamicRange)
    : mRegisteredClosestCommonInclusiveAncestor(nullptr),
      mIsPositioned(false),
      mIsGenerated(false),
      mCalledByJS(false),
      mIsDynamicRange(aIsDynamicRange) {
  mRefCnt.SetIsOnMainThread();
  Init(aNode);
}

AbstractRange::~AbstractRange() = default;

void AbstractRange::Init(nsINode* aNode) {
  MOZ_ASSERT(aNode, "range isn't in a document!");
  mOwner = aNode->OwnerDoc();
}

// static
void AbstractRange::Shutdown() {
  sHasShutDown = true;
  if (nsTArray<RefPtr<nsRange>>* cachedRanges = nsRange::sCachedRanges) {
    nsRange::sCachedRanges = nullptr;
    cachedRanges->Clear();
    delete cachedRanges;
  }
  if (nsTArray<RefPtr<StaticRange>>* cachedRanges =
          StaticRange::sCachedRanges) {
    StaticRange::sCachedRanges = nullptr;
    cachedRanges->Clear();
    delete cachedRanges;
  }
  if (nsTArray<RefPtr<CrossShadowBoundaryRange>>* cachedRanges =
          CrossShadowBoundaryRange::sCachedRanges) {
    CrossShadowBoundaryRange::sCachedRanges = nullptr;
    cachedRanges->Clear();
    delete cachedRanges;
  }
}

// static
template <class RangeType>
bool AbstractRange::MaybeCacheToReuse(RangeType& aInstance) {
  static const size_t kMaxRangeCache = 64;

  // If the instance is not used by JS and the cache is not yet full, we
  // should reuse it.  Otherwise, delete it.
  if (sHasShutDown || aInstance.GetWrapperMaybeDead() || aInstance.GetFlags() ||
      (RangeType::sCachedRanges &&
       RangeType::sCachedRanges->Length() == kMaxRangeCache)) {
    return false;
  }

  aInstance.ClearForReuse();

  if (!RangeType::sCachedRanges) {
    RangeType::sCachedRanges = new nsTArray<RefPtr<RangeType>>(16);
  }
  RangeType::sCachedRanges->AppendElement(&aInstance);
  return true;
}

nsINode* AbstractRange::GetClosestCommonInclusiveAncestor(
    AllowRangeCrossShadowBoundary aAllowCrossShadowBoundary) const {
  if (!mIsPositioned) {
    return nullptr;
  }
  nsINode* startContainer =
      aAllowCrossShadowBoundary == AllowRangeCrossShadowBoundary::Yes
          ? GetMayCrossShadowBoundaryStartContainer()
          : GetStartContainer();
  nsINode* endContainer =
      aAllowCrossShadowBoundary == AllowRangeCrossShadowBoundary::Yes
          ? GetMayCrossShadowBoundaryEndContainer()
          : GetEndContainer();

  if (MayCrossShadowBoundary() &&
      aAllowCrossShadowBoundary == AllowRangeCrossShadowBoundary::Yes) {
    // Since both the start container and the end container are
    // guaranteed to be in the same composed document.
    // If one of the boundary is a document, use that document
    // as the common ancestor since both nodes.
    const bool oneBoundaryIsDocument =
        (startContainer && startContainer->IsDocument()) ||
        (endContainer && endContainer->IsDocument());
    if (oneBoundaryIsDocument) {
      MOZ_ASSERT_IF(
          startContainer && startContainer->IsDocument(),
          !endContainer || endContainer->GetComposedDoc() == startContainer);
      MOZ_ASSERT_IF(
          endContainer && endContainer->IsDocument(),
          !startContainer || startContainer->GetComposedDoc() == endContainer);

      return startContainer ? startContainer->GetComposedDoc()
                            : endContainer->GetComposedDoc();
    }

    const auto rescope = [](nsINode*& aContainer) {
      if (!aContainer) {
        return;
      }
      // RangeBoundary allows the container to be shadow roots; When
      // this happens, we should use the shadow host here.
      if (auto* shadowRoot = ShadowRoot::FromNode(aContainer)) {
        aContainer = shadowRoot->GetHost();
        return;
      }
    };

    rescope(startContainer);
    rescope(endContainer);

    return nsContentUtils::GetCommonFlattenedTreeAncestorForSelection(
        startContainer ? startContainer->AsContent() : nullptr,
        endContainer ? endContainer->AsContent() : nullptr);
  }
  return nsContentUtils::GetClosestCommonInclusiveAncestor(startContainer,
                                                           endContainer);
}

// static
template <typename SPT, typename SRT, typename EPT, typename ERT,
          typename RangeType>
nsresult AbstractRange::SetStartAndEndInternal(
    const RangeBoundaryBase<SPT, SRT>& aStartBoundary,
    const RangeBoundaryBase<EPT, ERT>& aEndBoundary, RangeType* aRange) {
  if (NS_WARN_IF(!aStartBoundary.IsSet()) ||
      NS_WARN_IF(!aEndBoundary.IsSet())) {
    return NS_ERROR_INVALID_ARG;
  }

  nsINode* newStartRoot =
      RangeUtils::ComputeRootNode(aStartBoundary.Container());
  if (!newStartRoot) {
    return NS_ERROR_DOM_INVALID_NODE_TYPE_ERR;
  }
  if (!aStartBoundary.IsSetAndValid()) {
    return NS_ERROR_DOM_INDEX_SIZE_ERR;
  }

  if (aStartBoundary.Container() == aEndBoundary.Container()) {
    if (!aEndBoundary.IsSetAndValid()) {
      return NS_ERROR_DOM_INDEX_SIZE_ERR;
    }
    // XXX: Offsets - handle this more efficiently.
    // If the end offset is less than the start offset, this should be
    // collapsed at the end offset.
    if (*aStartBoundary.Offset(
            RangeBoundaryBase<SPT, SRT>::OffsetFilter::kValidOffsets) >
        *aEndBoundary.Offset(
            RangeBoundaryBase<EPT, ERT>::OffsetFilter::kValidOffsets)) {
      aRange->DoSetRange(aEndBoundary, aEndBoundary, newStartRoot);
    } else {
      aRange->DoSetRange(aStartBoundary, aEndBoundary, newStartRoot);
    }
    return NS_OK;
  }

  nsINode* newEndRoot = RangeUtils::ComputeRootNode(aEndBoundary.Container());
  if (!newEndRoot) {
    return NS_ERROR_DOM_INVALID_NODE_TYPE_ERR;
  }
  if (!aEndBoundary.IsSetAndValid()) {
    return NS_ERROR_DOM_INDEX_SIZE_ERR;
  }

  // Different root
  if (newStartRoot != newEndRoot) {
    if (aRange->IsStaticRange()) {
      // StaticRange allows nodes in different trees, so set start and end
      // accordingly
      aRange->DoSetRange(aStartBoundary, aEndBoundary, newEndRoot);
    } else {
      MOZ_ASSERT(aRange->IsDynamicRange());
      // In contrast, nsRange keeps both. It has a pair of start and end
      // which they have been collapsed to one end, and it also may have a pair
      // of start and end which are the original value.
      aRange->DoSetRange(aEndBoundary, aEndBoundary, newEndRoot);

      // Don't create the cross shadow bounday range if the one of the roots is
      // an UA widget regardless whether the boundaries are allowed to cross
      // shadow boundary or not.
      if (!IsRootUAWidget(newStartRoot) && !IsRootUAWidget(newEndRoot)) {
        aRange->AsDynamicRange()
            ->CreateOrUpdateCrossShadowBoundaryRangeIfNeeded(aStartBoundary,
                                                             aEndBoundary);
      }
    }
    return NS_OK;
  }

  const Maybe<int32_t> pointOrder =
      nsContentUtils::ComparePoints(aStartBoundary, aEndBoundary);
  if (!pointOrder) {
    // Safely return a value but also detected this in debug builds.
    MOZ_ASSERT_UNREACHABLE();
    return NS_ERROR_INVALID_ARG;
  }

  // If the end point is before the start point, this should be collapsed at
  // the end point.
  if (*pointOrder == 1) {
    aRange->DoSetRange(aEndBoundary, aEndBoundary, newEndRoot);
    return NS_OK;
  }

  // Otherwise, set the range as specified.
  aRange->DoSetRange(aStartBoundary, aEndBoundary, newStartRoot);
  return NS_OK;
}

bool AbstractRange::IsInSelection(const Selection& aSelection) const {
  return mSelections.Contains(&aSelection);
}

void AbstractRange::RegisterSelection(Selection& aSelection) {
  if (IsInSelection(aSelection)) {
    return;
  }
  bool isFirstSelection = mSelections.IsEmpty();
  mSelections.AppendElement(&aSelection);
  if (isFirstSelection && !mRegisteredClosestCommonInclusiveAncestor) {
    nsINode* commonAncestor = GetClosestCommonInclusiveAncestor(
        StaticPrefs::dom_shadowdom_selection_across_boundary_enabled()
            ? AllowRangeCrossShadowBoundary::Yes
            : AllowRangeCrossShadowBoundary::No);
    MOZ_ASSERT(commonAncestor, "unexpected disconnected nodes");
    RegisterClosestCommonInclusiveAncestor(commonAncestor);
  }
}

const nsTArray<WeakPtr<Selection>>& AbstractRange::GetSelections() const {
  return mSelections;
}

void AbstractRange::UnregisterSelection(const Selection& aSelection) {
  mSelections.RemoveElement(&aSelection);
  if (mSelections.IsEmpty() && mRegisteredClosestCommonInclusiveAncestor) {
    UnregisterClosestCommonInclusiveAncestor();
    MOZ_DIAGNOSTIC_ASSERT(
        !mRegisteredClosestCommonInclusiveAncestor,
        "How can we have a registered common ancestor when we "
        "just unregistered?");
    MOZ_DIAGNOSTIC_ASSERT(
        !isInList(),
        "Shouldn't be registered if we have no "
        "mRegisteredClosestCommonInclusiveAncestor after unregistering");
  }
}

void AbstractRange::RegisterClosestCommonInclusiveAncestor(nsINode* aNode) {
  MOZ_ASSERT(aNode, "bad arg");

  MOZ_DIAGNOSTIC_ASSERT(IsInAnySelection(),
                        "registering range not in selection");

  mRegisteredClosestCommonInclusiveAncestor = aNode;

  MarkDescendants(*aNode);

  UniquePtr<LinkedList<AbstractRange>>& ranges =
      aNode->GetClosestCommonInclusiveAncestorRangesPtr();
  if (!ranges) {
    ranges = MakeUnique<LinkedList<AbstractRange>>();
  }

  MOZ_DIAGNOSTIC_ASSERT(!isInList());
  ranges->insertBack(this);
  aNode->SetClosestCommonInclusiveAncestorForRangeInSelection();
}

void AbstractRange::UnregisterClosestCommonInclusiveAncestor(
    bool aIsUnlinking) {
  if (!mRegisteredClosestCommonInclusiveAncestor) {
    return;
  }
  nsCOMPtr oldClosestCommonInclusiveAncestor =
      mRegisteredClosestCommonInclusiveAncestor;
  mRegisteredClosestCommonInclusiveAncestor = nullptr;
  LinkedList<AbstractRange>* ranges =
      oldClosestCommonInclusiveAncestor
          ->GetExistingClosestCommonInclusiveAncestorRanges();
  MOZ_ASSERT(ranges);

#ifdef DEBUG
  bool found = false;
  for (AbstractRange* range : *ranges) {
    if (range == this) {
      found = true;
      break;
    }
  }
  MOZ_ASSERT(found,
             "We should be in the list on our registered common ancestor");
#endif  // DEBUG

  remove();

  // We don't want to waste time unmarking flags on nodes that are
  // being unlinked anyway.
  if (!aIsUnlinking && ranges->isEmpty()) {
    oldClosestCommonInclusiveAncestor
        ->ClearClosestCommonInclusiveAncestorForRangeInSelection();
    UnmarkDescendants(*oldClosestCommonInclusiveAncestor);
  }
  oldClosestCommonInclusiveAncestor = nullptr;
}

void AbstractRange::UpdateCommonAncestorIfNecessary() {
  nsINode* oldCommonAncestor = mRegisteredClosestCommonInclusiveAncestor;
  nsINode* newCommonAncestor =
      GetClosestCommonInclusiveAncestor(AllowRangeCrossShadowBoundary::Yes);
  if (newCommonAncestor != oldCommonAncestor) {
    UnregisterClosestCommonInclusiveAncestor();

    if (newCommonAncestor) {
      RegisterClosestCommonInclusiveAncestor(newCommonAncestor);
    } else {
      MOZ_DIAGNOSTIC_ASSERT(!mIsPositioned, "unexpected disconnected nodes");
      mSelections.Clear();
      MOZ_DIAGNOSTIC_ASSERT(
          !mRegisteredClosestCommonInclusiveAncestor,
          "How can we have a registered common ancestor when we "
          "didn't register ourselves?");
      MOZ_DIAGNOSTIC_ASSERT(!isInList(),
                            "Shouldn't be registered if we have no "
                            "mRegisteredClosestCommonInclusiveAncestor");
    }
  }
}

const RangeBoundary& AbstractRange::MayCrossShadowBoundaryStartRef() const {
  return IsDynamicRange() ? AsDynamicRange()->MayCrossShadowBoundaryStartRef()
                          : mStart;
}

const RangeBoundary& AbstractRange::MayCrossShadowBoundaryEndRef() const {
  return IsDynamicRange() ? AsDynamicRange()->MayCrossShadowBoundaryEndRef()
                          : mEnd;
}

nsIContent* AbstractRange::GetMayCrossShadowBoundaryChildAtStartOffset() const {
  return IsDynamicRange()
             ? AsDynamicRange()->GetMayCrossShadowBoundaryChildAtStartOffset()
             : mStart.GetChildAtOffset();
}

nsIContent* AbstractRange::GetMayCrossShadowBoundaryChildAtEndOffset() const {
  return IsDynamicRange()
             ? AsDynamicRange()->GetMayCrossShadowBoundaryChildAtEndOffset()
             : mEnd.GetChildAtOffset();
}

nsINode* AbstractRange::GetMayCrossShadowBoundaryStartContainer() const {
  return IsDynamicRange()
             ? AsDynamicRange()->GetMayCrossShadowBoundaryStartContainer()
             : mStart.Container();
}

nsINode* AbstractRange::GetMayCrossShadowBoundaryEndContainer() const {
  return IsDynamicRange()
             ? AsDynamicRange()->GetMayCrossShadowBoundaryEndContainer()
             : mEnd.Container();
}

bool AbstractRange::MayCrossShadowBoundary() const {
  return IsDynamicRange() ? !!AsDynamicRange()->GetCrossShadowBoundaryRange()
                          : false;
}

uint32_t AbstractRange::MayCrossShadowBoundaryStartOffset() const {
  return IsDynamicRange()
             ? AsDynamicRange()->MayCrossShadowBoundaryStartOffset()
             : static_cast<uint32_t>(*mStart.Offset(
                   RangeBoundary::OffsetFilter::kValidOrInvalidOffsets));
}

uint32_t AbstractRange::MayCrossShadowBoundaryEndOffset() const {
  return IsDynamicRange()
             ? AsDynamicRange()->MayCrossShadowBoundaryEndOffset()
             : static_cast<uint32_t>(*mEnd.Offset(
                   RangeBoundary::OffsetFilter::kValidOrInvalidOffsets));
}

nsINode* AbstractRange::GetParentObject() const { return mOwner; }

JSObject* AbstractRange::WrapObject(JSContext* aCx,
                                    JS::Handle<JSObject*> aGivenProto) {
  MOZ_CRASH("Must be overridden");
}

bool AbstractRange::AreNormalRangeAndCrossShadowBoundaryRangeCollapsed() const {
  if (!Collapsed()) {
    return false;
  }

  // We know normal range is collapsed at this point
  if (IsStaticRange()) {
    return true;
  }

  if (const CrossShadowBoundaryRange* crossShadowBoundaryRange =
          AsDynamicRange()->GetCrossShadowBoundaryRange()) {
    return crossShadowBoundaryRange->Collapsed();
  }

  return true;
}

void AbstractRange::ClearForReuse() {
  mOwner = nullptr;
  mStart = RangeBoundary();
  mEnd = RangeBoundary();
  mIsPositioned = false;
  mIsGenerated = false;
  mCalledByJS = false;
}

/*static*/
bool AbstractRange::IsRootUAWidget(const nsINode* aRoot) {
  MOZ_ASSERT(aRoot);
  if (const ShadowRoot* shadowRoot = ShadowRoot::FromNode(aRoot)) {
    return shadowRoot->IsUAWidget();
  }
  return false;
}
}  // namespace mozilla::dom

quality97%

¤ Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.0.18Bemerkung: (vorverarbeitet) ¤

*Bot Zugriff

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.