gecko-dev/editor/libeditor/EditorDOMPoint.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */
#ifndef mozilla_EditorDOMPoint_h
#define mozilla_EditorDOMPoint_h
#include "mozilla/Assertions.h"
#include "mozilla/Attributes.h"
#include "mozilla/RangeBoundary.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/Text.h"
#include "nsAtom.h"
#include "nsCOMPtr.h"
#include "nsGkAtoms.h"
#include "nsIContent.h"
#include "nsINode.h"
namespace mozilla {
template <typename ParentType, typename ChildType>
class EditorDOMPointBase;
/**
* EditorDOMPoint and EditorRawDOMPoint are simple classes which refers
* a point in the DOM tree at creating the instance or initializing the
* instance with calling Set().
*
* EditorDOMPoint refers container node (and child node if it's already set)
* with nsCOMPtr. EditorRawDOMPoint refers them with raw pointer.
* So, EditorRawDOMPoint is useful when you access the nodes only before
* changing DOM tree since increasing refcount may appear in micro benchmark
* if it's in a hot path. On the other hand, if you need to refer them even
* after changing DOM tree, you must use EditorDOMPoint.
*
* When initializing an instance only with child node or offset, the instance
* starts to refer the child node or offset in the container. In this case,
* the other information hasn't been initialized due to performance reason.
* When you retrieve the other information with calling Offset() or
* GetChild(), the other information is computed with the current DOM tree.
* Therefore, e.g., in the following case, the other information may be
* different:
*
* EditorDOMPoint pointA(container1, childNode1);
* EditorDOMPoint pointB(container1, childNode1);
* Unused << pointA.Offset(); // The offset is computed now.
* container1->RemoveChild(childNode1->GetPreviousSibling());
* Unused << pointB.Offset(); // Now, pointB.Offset() equals pointA.Offset() - 1
*
* similarly:
*
* EditorDOMPoint pointA(container1, 5);
* EditorDOMPoint pointB(container1, 5);
* Unused << pointA.GetChild(); // The child is computed now.
* container1->RemoveChild(childNode1->GetFirstChild());
* Unused << pointB.GetChild(); // Now, pointB.GetChild() equals
* // pointA.GetChild()->GetPreviousSibling().
*
* So, when you initialize an instance only with one information, you need to
* be careful when you access the other information after changing the DOM tree.
* When you need to lock the child node or offset and recompute the other
* information with new DOM tree, you can use
* AutoEditorDOMPointOffsetInvalidator and AutoEditorDOMPointChildInvalidator.
*/
typedef EditorDOMPointBase<nsCOMPtr<nsINode>, nsCOMPtr<nsIContent>>
EditorDOMPoint;
typedef EditorDOMPointBase<nsINode*, nsIContent*> EditorRawDOMPoint;
template <typename ParentType, typename ChildType>
class EditorDOMPointBase final {
typedef EditorDOMPointBase<ParentType, ChildType> SelfType;
public:
EditorDOMPointBase()
: mParent(nullptr), mChild(nullptr), mIsChildInitialized(false) {}
template <typename ContainerType>
EditorDOMPointBase(ContainerType aContainer, int32_t aOffset)
: mParent(aContainer),
mChild(nullptr),
mOffset(mozilla::Some(aOffset)),
mIsChildInitialized(false) {
NS_WARNING_ASSERTION(
!mParent || mOffset.value() <= mParent->Length(),
"The offset is larger than the length of aContainer or negative");
if (!mParent) {
mOffset.reset();
}
}
/**
* Different from RangeBoundary, aPointedNode should be a child node
* which you want to refer.
*/
explicit EditorDOMPointBase(nsINode* aPointedNode)
: mParent(aPointedNode && aPointedNode->IsContent()
? aPointedNode->GetParentNode()
: nullptr),
mChild(aPointedNode && aPointedNode->IsContent()
? aPointedNode->AsContent()
: nullptr),
mIsChildInitialized(false) {
mIsChildInitialized = aPointedNode && mChild;
NS_WARNING_ASSERTION(IsSet(),
"The child is nullptr or doesn't have its parent");
NS_WARNING_ASSERTION(mChild && mChild->GetParentNode() == mParent,
"Initializing RangeBoundary with invalid value");
}
EditorDOMPointBase(nsINode* aContainer, nsIContent* aPointedNode,
int32_t aOffset)
: mParent(aContainer),
mChild(aPointedNode),
mOffset(mozilla::Some(aOffset)),
mIsChildInitialized(true) {
MOZ_DIAGNOSTIC_ASSERT(
aContainer, "This constructor shouldn't be used when pointing nowhere");
MOZ_ASSERT(mOffset.value() <= mParent->Length());
MOZ_ASSERT(mChild || mParent->Length() == mOffset.value() ||
!mParent->IsContainerNode());
MOZ_ASSERT(!mChild || mParent == mChild->GetParentNode());
MOZ_ASSERT(mParent->GetChildAt_Deprecated(mOffset.value()) == mChild);
}
template <typename PT, typename CT>
explicit EditorDOMPointBase(const RangeBoundaryBase<PT, CT>& aOther)
: mParent(aOther.mParent),
mChild(aOther.mRef ? aOther.mRef->GetNextSibling()
: (aOther.mParent ? aOther.mParent->GetFirstChild()
: nullptr)),
mOffset(aOther.mOffset),
mIsChildInitialized(aOther.mRef || (aOther.mOffset.isSome() &&
!aOther.mOffset.value())) {}
template <typename PT, typename CT>
MOZ_IMPLICIT EditorDOMPointBase(const EditorDOMPointBase<PT, CT>& aOther)
: mParent(aOther.mParent),
mChild(aOther.mChild),
mOffset(aOther.mOffset),
mIsChildInitialized(aOther.mIsChildInitialized) {}
/**
* GetContainer() returns the container node at the point.
* GetContainerAs*() returns the container node as specific type.
*/
nsINode* GetContainer() const { return mParent; }
nsIContent* GetContainerAsContent() const {
return mParent && mParent->IsContent() ? mParent->AsContent() : nullptr;
}
dom::Element* GetContainerAsElement() const {
return Element::FromNodeOrNull(mParent);
}
dom::Text* GetContainerAsText() const {
return mParent ? mParent->GetAsText() : nullptr;
}
/**
* CanContainerHaveChildren() returns true if the container node can have
* child nodes. Otherwise, e.g., when the container is a text node, returns
* false.
*/
bool CanContainerHaveChildren() const {
return mParent && mParent->IsContainerNode();
}
/**
* IsInDataNode() returns true if the container node is a data node including
* text node.
*/
bool IsInDataNode() const { return mParent && mParent->IsCharacterData(); }
/**
* IsInTextNode() returns true if the container node is a text node.
*/
bool IsInTextNode() const { return mParent && mParent->IsText(); }
/**
* IsInNativeAnonymousSubtree() returns true if the container is in
* native anonymous subtree.
*/
bool IsInNativeAnonymousSubtree() const {
return mParent && mParent->IsInNativeAnonymousSubtree();
}
/**
* IsContainerHTMLElement() returns true if the container node is an HTML
* element node and its node name is aTag.
*/
bool IsContainerHTMLElement(nsAtom* aTag) const {
return mParent && mParent->IsHTMLElement(aTag);
}
/**
* IsContainerAnyOfHTMLElements() returns true if the container node is an
* HTML element node and its node name is one of the arguments.
*/
template <typename First, typename... Args>
bool IsContainerAnyOfHTMLElements(First aFirst, Args... aArgs) const {
return mParent && mParent->IsAnyOfHTMLElements(aFirst, aArgs...);
}
/**
* GetChild() returns a child node which is pointed by the instance.
* If mChild hasn't been initialized yet, this computes the child node
* from mParent and mOffset with *current* DOM tree.
*/
nsIContent* GetChild() const {
if (!mParent || !mParent->IsContainerNode()) {
return nullptr;
}
if (mIsChildInitialized) {
return mChild;
}
// Fix child node now.
const_cast<SelfType*>(this)->EnsureChild();
return mChild;
}
/**
* GetNextSiblingOfChild() returns next sibling of the child node.
* If this refers after the last child or the container cannot have children,
* this returns nullptr with warning.
* If mChild hasn't been initialized yet, this computes the child node
* from mParent and mOffset with *current* DOM tree.
*/
nsIContent* GetNextSiblingOfChild() const {
if (NS_WARN_IF(!mParent) || NS_WARN_IF(!mParent->IsContainerNode())) {
return nullptr;
}
if (mIsChildInitialized) {
return mChild ? mChild->GetNextSibling() : nullptr;
}
MOZ_ASSERT(mOffset.isSome());
if (NS_WARN_IF(mOffset.value() > mParent->Length())) {
// If this has been set only offset and now the offset is invalid,
// let's just return nullptr.
return nullptr;
}
// Fix child node now.
const_cast<SelfType*>(this)->EnsureChild();
return mChild ? mChild->GetNextSibling() : nullptr;
}
/**
* GetPreviousSiblingOfChild() returns previous sibling of a child
* at offset. If this refers the first child or the container cannot have
* children, this returns nullptr with warning.
* If mChild hasn't been initialized yet, this computes the child node
* from mParent and mOffset with *current* DOM tree.
*/
nsIContent* GetPreviousSiblingOfChild() const {
if (NS_WARN_IF(!mParent) || NS_WARN_IF(!mParent->IsContainerNode())) {
return nullptr;
}
if (mIsChildInitialized) {
return mChild ? mChild->GetPreviousSibling() : mParent->GetLastChild();
}
MOZ_ASSERT(mOffset.isSome());
if (NS_WARN_IF(mOffset.value() > mParent->Length())) {
// If this has been set only offset and now the offset is invalid,
// let's just return nullptr.
return nullptr;
}
// Fix child node now.
const_cast<SelfType*>(this)->EnsureChild();
return mChild ? mChild->GetPreviousSibling() : mParent->GetLastChild();
}
uint32_t Offset() const {
if (mOffset.isSome()) {
MOZ_ASSERT(mOffset.isSome());
return mOffset.value();
}
if (!mParent) {
MOZ_ASSERT(!mChild);
return 0;
}
MOZ_ASSERT(mParent->IsContainerNode(),
"If the container cannot have children, mOffset.isSome() should "
"be true");
if (!mChild) {
// We're referring after the last child. Fix offset now.
const_cast<SelfType*>(this)->mOffset = mozilla::Some(mParent->Length());
return mOffset.value();
}
MOZ_ASSERT(mChild->GetParentNode() == mParent);
// Fix offset now.
if (mChild == mParent->GetFirstChild()) {
const_cast<SelfType*>(this)->mOffset = mozilla::Some(0);
} else {
const_cast<SelfType*>(this)->mOffset =
mozilla::Some(mParent->ComputeIndexOf(mChild));
}
return mOffset.value();
}
/**
* Set() sets a point to aOffset or aChild.
* If it's set with aOffset, mChild is invalidated. If it's set with aChild,
* mOffset may be invalidated.
*/
void Set(nsINode* aContainer, int32_t aOffset) {
mParent = aContainer;
mChild = nullptr;
mOffset = mozilla::Some(aOffset);
mIsChildInitialized = false;
NS_ASSERTION(!mParent || mOffset.value() <= mParent->Length(),
"The offset is out of bounds");
}
void Set(const nsINode* aChild) {
MOZ_ASSERT(aChild);
if (NS_WARN_IF(!aChild->IsContent())) {
Clear();
return;
}
mParent = aChild->GetParentNode();
mChild = const_cast<nsIContent*>(aChild->AsContent());
mOffset.reset();
mIsChildInitialized = true;
}
/**
* SetToEndOf() sets this to the end of aContainer. Then, mChild is always
* nullptr but marked as initialized and mOffset is always set.
*/
void SetToEndOf(const nsINode* aContainer) {
MOZ_ASSERT(aContainer);
mParent = const_cast<nsINode*>(aContainer);
mChild = nullptr;
mOffset = mozilla::Some(mParent->Length());
mIsChildInitialized = true;
}
/**
* SetAfter() sets mChild to next sibling of aChild.
*/
void SetAfter(const nsINode* aChild) {
MOZ_ASSERT(aChild);
nsIContent* nextSibling = aChild->GetNextSibling();
if (nextSibling) {
Set(nextSibling);
return;
}
nsINode* parentNode = aChild->GetParentNode();
if (NS_WARN_IF(!parentNode)) {
Clear();
return;
}
SetToEndOf(parentNode);
}
/**
* Clear() makes the instance not point anywhere.
*/
void Clear() {
mParent = nullptr;
mChild = nullptr;
mOffset.reset();
mIsChildInitialized = false;
}
/**
* AdvanceOffset() tries to refer next sibling of mChild and/of next offset.
* If the container can have children and there is no next sibling or the
* offset reached the length of the container, this outputs warning and does
* nothing. So, callers need to check if there is next sibling which you
* need to refer.
*
* @return true if there is a next DOM point to refer.
*/
bool AdvanceOffset() {
if (NS_WARN_IF(!mParent)) {
return false;
}
// If only mOffset is available, just compute the offset.
if ((mOffset.isSome() && !mIsChildInitialized) ||
!mParent->IsContainerNode()) {
MOZ_ASSERT(mOffset.isSome());
MOZ_ASSERT(!mChild);
if (NS_WARN_IF(mOffset.value() >= mParent->Length())) {
// We're already referring the start of the container.
return false;
}
mOffset = mozilla::Some(mOffset.value() + 1);
return true;
}
MOZ_ASSERT(mIsChildInitialized);
MOZ_ASSERT(!mOffset.isSome() || mOffset.isSome());
if (NS_WARN_IF(!mParent->HasChildren()) || NS_WARN_IF(!mChild) ||
NS_WARN_IF(mOffset.isSome() && mOffset.value() >= mParent->Length())) {
// We're already referring the end of the container (or outside).
return false;
}
if (mOffset.isSome()) {
MOZ_ASSERT(mOffset.isSome());
mOffset = mozilla::Some(mOffset.value() + 1);
}
mChild = mChild->GetNextSibling();
return true;
}
/**
* RewindOffset() tries to refer previous sibling of mChild and/or previous
* offset. If the container can have children and there is no next previous
* or the offset is 0, this outputs warning and does nothing. So, callers
* need to check if there is previous sibling which you need to refer.
*
* @return true if there is a previous DOM point to refer.
*/
bool RewindOffset() {
if (NS_WARN_IF(!mParent)) {
return false;
}
// If only mOffset is available, just compute the offset.
if ((mOffset.isSome() && !mIsChildInitialized) ||
!mParent->IsContainerNode()) {
MOZ_ASSERT(mOffset.isSome());
MOZ_ASSERT(!mChild);
if (NS_WARN_IF(!mOffset.value()) ||
NS_WARN_IF(mOffset.value() > mParent->Length())) {
// We're already referring the start of the container or
// the offset is invalid since perhaps, the offset was set before
// the last DOM tree change.
return false;
}
mOffset = mozilla::Some(mOffset.value() - 1);
return true;
}
MOZ_ASSERT(mIsChildInitialized);
MOZ_ASSERT(!mOffset.isSome() || mOffset.isSome());
if (NS_WARN_IF(!mParent->HasChildren()) ||
NS_WARN_IF(mChild && !mChild->GetPreviousSibling()) ||
NS_WARN_IF(mOffset.isSome() && !mOffset.value())) {
// We're already referring the start of the container (or the child has
// been moved from the container?).
return false;
}
nsIContent* previousSibling =
mChild ? mChild->GetPreviousSibling() : mParent->GetLastChild();
if (NS_WARN_IF(!previousSibling)) {
// We're already referring the first child of the container.
return false;
}
if (mOffset.isSome()) {
mOffset = mozilla::Some(mOffset.value() - 1);
}
mChild = previousSibling;
return true;
}
/**
* GetNonAnonymousSubtreePoint() returns a DOM point which is NOT in
* native-anonymous subtree. If the instance isn't in native-anonymous
* subtree, this returns same point. Otherwise, climbs up until finding
* non-native-anonymous parent and returns the point of it. I.e.,
* container is parent of the found non-anonymous-native node.
*/
EditorRawDOMPoint GetNonAnonymousSubtreePoint() const {
if (NS_WARN_IF(!IsSet())) {
return EditorRawDOMPoint();
}
if (!IsInNativeAnonymousSubtree()) {
return EditorRawDOMPoint(*this);
}
nsINode* parent;
for (parent = mParent->GetParentNode();
parent && parent->IsInNativeAnonymousSubtree();
parent = mParent->GetParentNode()) {
}
if (!parent) {
return EditorRawDOMPoint();
}
return EditorRawDOMPoint(parent);
}
bool IsSet() const {
return mParent && (mIsChildInitialized || mOffset.isSome());
}
bool IsSetAndValid() const {
if (!IsSet()) {
return false;
}
if (mChild && mChild->GetParentNode() != mParent) {
return false;
}
if (mOffset.isSome() && mOffset.value() > mParent->Length()) {
return false;
}
return true;
}
bool HasChildMovedFromContainer() const {
return mChild && mChild->GetParentNode() != mParent;
}
bool IsStartOfContainer() const {
// If we're referring the first point in the container:
// If mParent is not a container like a text node, mOffset is 0.
// If mChild is initialized and it's first child of mParent.
// If mChild isn't initialized and the offset is 0.
if (NS_WARN_IF(!mParent)) {
return false;
}
if (!mParent->IsContainerNode()) {
return !mOffset.value();
}
if (mIsChildInitialized) {
if (mParent->GetFirstChild() == mChild) {
NS_WARNING_ASSERTION(!mOffset.isSome() || !mOffset.value(),
"If mOffset was initialized, it should be 0");
return true;
}
NS_WARNING_ASSERTION(!mOffset.isSome() || mParent->GetChildAt_Deprecated(
mOffset.value()) == mChild,
"If mOffset and mChild are mismatched");
return false;
}
MOZ_ASSERT(mOffset.isSome());
return !mOffset.value();
}
bool IsEndOfContainer() const {
// If we're referring after the last point of the container:
// If mParent is not a container like text node, mOffset is same as the
// length of the container.
// If mChild is initialized and it's nullptr.
// If mChild isn't initialized and mOffset is same as the length of the
// container.
if (NS_WARN_IF(!mParent)) {
return false;
}
if (!mParent->IsContainerNode()) {
return mOffset.value() == mParent->Length();
}
if (mIsChildInitialized) {
if (!mChild) {
NS_WARNING_ASSERTION(
!mOffset.isSome() || mOffset.value() == mParent->Length(),
"If mOffset was initialized, it should be length of the container");
return true;
}
NS_WARNING_ASSERTION(!mOffset.isSome() || mParent->GetChildAt_Deprecated(
mOffset.value()) == mChild,
"If mOffset and mChild are mismatched");
return false;
}
MOZ_ASSERT(mOffset.isSome());
return mOffset.value() == mParent->Length();
}
bool IsBRElementAtEndOfContainer() const {
if (NS_WARN_IF(!mParent)) {
return false;
}
if (!mParent->IsContainerNode()) {
return false;
}
const_cast<SelfType*>(this)->EnsureChild();
if (!mChild || mChild->GetNextSibling()) {
return false;
}
return mChild->IsHTMLElement(nsGkAtoms::br);
}
template <typename A, typename B>
EditorDOMPointBase& operator=(const RangeBoundaryBase<A, B>& aOther) {
mParent = aOther.mParent;
mChild = aOther.mRef ? aOther.mRef->GetNextSibling()
: (aOther.mParent && aOther.mParent->IsContainerNode()
? aOther.mParent->GetFirstChild()
: nullptr);
mOffset = aOther.mOffset;
mIsChildInitialized =
aOther.mRef || (aOther.mParent && !aOther.mParent->IsContainerNode()) ||
(aOther.mOffset.isSome() && !aOther.mOffset.value());
return *this;
}
template <typename A, typename B>
EditorDOMPointBase& operator=(const EditorDOMPointBase<A, B>& aOther) {
mParent = aOther.mParent;
mChild = aOther.mChild;
mOffset = aOther.mOffset;
mIsChildInitialized = aOther.mIsChildInitialized;
return *this;
}
template <typename A, typename B>
bool operator==(const EditorDOMPointBase<A, B>& aOther) const {
if (mParent != aOther.mParent) {
return false;
}
if (mOffset.isSome() && aOther.mOffset.isSome()) {
// If both mOffset are set, we need to compare both mRef too because
// the relation of mRef and mOffset have already broken by DOM tree
// changes.
if (mOffset != aOther.mOffset) {
return false;
}
if (mChild == aOther.mChild) {
return true;
}
if (NS_WARN_IF(mIsChildInitialized && aOther.mIsChildInitialized)) {
// In this case, relation between mChild and mOffset of one of or both
// of them doesn't match with current DOM tree since the DOM tree might
// have been changed after computing mChild or mOffset.
return false;
}
// If one of mChild hasn't been computed yet, we should compare them only
// with mOffset. Perhaps, we shouldn't copy mChild from non-nullptr one
// to the other since if we copy it here, it may be unexpected behavior
// for some callers.
return true;
}
MOZ_ASSERT(mIsChildInitialized || aOther.mIsChildInitialized);
if (mOffset.isSome() && !mIsChildInitialized && !aOther.mOffset.isSome() &&
aOther.mIsChildInitialized) {
// If this has only mOffset and the other has only mChild, this needs to
// compute mChild now.
const_cast<SelfType*>(this)->EnsureChild();
return mChild == aOther.mChild;
}
if (!mOffset.isSome() && mIsChildInitialized && aOther.mOffset.isSome() &&
!aOther.mIsChildInitialized) {
// If this has only mChild and the other has only mOffset, the other needs
// to compute mChild now.
const_cast<EditorDOMPointBase<A, B>&>(aOther).EnsureChild();
return mChild == aOther.mChild;
}
// If mOffset of one of them hasn't been computed from mChild yet, we should
// compare only with mChild. Perhaps, we shouldn't copy mOffset from being
// some one to not being some one since if we copy it here, it may be
// unexpected behavior for some callers.
return mChild == aOther.mChild;
}
template <typename A, typename B>
bool operator!=(const EditorDOMPointBase<A, B>& aOther) const {
return !(*this == aOther);
}
/**
* This operator should be used if API of other modules take RawRangeBoundary,
* e.g., methods of Selection and nsRange.
*/
operator const RawRangeBoundary() const { return ToRawRangeBoundary(); }
const RawRangeBoundary ToRawRangeBoundary() const {
if (!IsSet() || NS_WARN_IF(!mIsChildInitialized && !mOffset.isSome())) {
return RawRangeBoundary();
}
if (!mParent->IsContainerNode()) {
// If the container is a data node like a text node, we need to create
// RangeBoundaryBase instance only with mOffset because mChild is always
// nullptr.
return RawRangeBoundary(mParent, mOffset.value());
}
if (mIsChildInitialized && mOffset.isSome()) {
// If we've already set both child and offset, we should create
// RangeBoundary with offset after validation.
#ifdef DEBUG
if (mChild) {
MOZ_ASSERT(mParent == mChild->GetParentNode());
MOZ_ASSERT(mParent->GetChildAt_Deprecated(mOffset.value()) == mChild);
} else {
MOZ_ASSERT(mParent->Length() == mOffset.value());
}
#endif // #ifdef DEBUG
return RawRangeBoundary(mParent, mOffset.value());
}
// Otherwise, we should create RangeBoundaryBase only with available
// information.
if (mOffset.isSome()) {
return RawRangeBoundary(mParent, mOffset.value());
}
if (mChild) {
return RawRangeBoundary(mParent, mChild->GetPreviousSibling());
}
return RawRangeBoundary(mParent, mParent->GetLastChild());
}
private:
void EnsureChild() {
if (mIsChildInitialized) {
return;
}
if (!mParent) {
MOZ_ASSERT(!mOffset.isSome());
return;
}
MOZ_ASSERT(mOffset.isSome());
MOZ_ASSERT(mOffset.value() <= mParent->Length());
mIsChildInitialized = true;
if (!mParent->IsContainerNode()) {
return;
}
mChild = mParent->GetChildAt_Deprecated(mOffset.value());
MOZ_ASSERT(mChild || mOffset.value() == mParent->Length());
}
ParentType mParent;
ChildType mChild;
mozilla::Maybe<uint32_t> mOffset;
bool mIsChildInitialized;
template <typename PT, typename CT>
friend class EditorDOMPointBase;
friend void ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback&,
EditorDOMPoint&, const char*,
uint32_t);
friend void ImplCycleCollectionUnlink(EditorDOMPoint&);
};
inline void ImplCycleCollectionUnlink(EditorDOMPoint& aField) {
ImplCycleCollectionUnlink(aField.mParent);
ImplCycleCollectionUnlink(aField.mChild);
}
inline void ImplCycleCollectionTraverse(
nsCycleCollectionTraversalCallback& aCallback, EditorDOMPoint& aField,
const char* aName, uint32_t aFlags) {
ImplCycleCollectionTraverse(aCallback, aField.mParent, "mParent", 0);
ImplCycleCollectionTraverse(aCallback, aField.mChild, "mChild", 0);
}
/**
* AutoEditorDOMPointOffsetInvalidator is useful if DOM tree will be changed
* when EditorDOMPoint instance is available and keeps referring same child
* node.
*
* This class automatically guarantees that given EditorDOMPoint instance
* stores the child node and invalidates its offset when the instance is
* destroyed. Additionally, users of this class can invalidate the offset
* manually when they need.
*/
class MOZ_STACK_CLASS AutoEditorDOMPointOffsetInvalidator final {
public:
explicit AutoEditorDOMPointOffsetInvalidator(EditorDOMPoint& aPoint)
: mPoint(aPoint), mCanceled(false) {
MOZ_ASSERT(aPoint.IsSetAndValid());
MOZ_ASSERT(mPoint.CanContainerHaveChildren());
mChild = mPoint.GetChild();
}
~AutoEditorDOMPointOffsetInvalidator() {
if (!mCanceled) {
InvalidateOffset();
}
}
/**
* Manually, invalidate offset of the given point.
*/
void InvalidateOffset() {
if (mChild) {
mPoint.Set(mChild);
} else {
// If the point referred after the last child, let's keep referring
// after current last node of the old container.
mPoint.SetToEndOf(mPoint.GetContainer());
}
}
/**
* After calling Cancel(), mPoint won't be modified by the destructor.
*/
void Cancel() { mCanceled = true; }
private:
EditorDOMPoint& mPoint;
// Needs to store child node by ourselves because EditorDOMPoint stores
// child node with mRef which is previous sibling of current child node.
// Therefore, we cannot keep referring it if it's first child.
nsCOMPtr<nsIContent> mChild;
bool mCanceled;
AutoEditorDOMPointOffsetInvalidator() = delete;
AutoEditorDOMPointOffsetInvalidator(
const AutoEditorDOMPointOffsetInvalidator& aOther) = delete;
const AutoEditorDOMPointOffsetInvalidator& operator=(
const AutoEditorDOMPointOffsetInvalidator& aOther) = delete;
};
/**
* AutoEditorDOMPointChildInvalidator is useful if DOM tree will be changed
* when EditorDOMPoint instance is available and keeps referring same container
* and offset in it.
*
* This class automatically guarantees that given EditorDOMPoint instance
* stores offset and invalidates its child node when the instance is destroyed.
* Additionally, users of this class can invalidate the child manually when
* they need.
*/
class MOZ_STACK_CLASS AutoEditorDOMPointChildInvalidator final {
public:
explicit AutoEditorDOMPointChildInvalidator(EditorDOMPoint& aPoint)
: mPoint(aPoint), mCanceled(false) {
MOZ_ASSERT(aPoint.IsSetAndValid());
Unused << mPoint.Offset();
}
~AutoEditorDOMPointChildInvalidator() {
if (!mCanceled) {
InvalidateChild();
}
}
/**
* Manually, invalidate child of the given point.
*/
void InvalidateChild() { mPoint.Set(mPoint.GetContainer(), mPoint.Offset()); }
/**
* After calling Cancel(), mPoint won't be modified by the destructor.
*/
void Cancel() { mCanceled = true; }
private:
EditorDOMPoint& mPoint;
bool mCanceled;
AutoEditorDOMPointChildInvalidator() = delete;
AutoEditorDOMPointChildInvalidator(
const AutoEditorDOMPointChildInvalidator& aOther) = delete;
const AutoEditorDOMPointChildInvalidator& operator=(
const AutoEditorDOMPointChildInvalidator& aOther) = delete;
};
} // namespace mozilla
#endif // #ifndef mozilla_EditorDOMPoint_h