/* 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_ConnectedAncestorTracker_h #define mozilla_ConnectedAncestorTracker_h #include "mozilla/Attributes.h" #include "mozilla/PresShell.h" #include "mozilla/dom/Document.h" #include "mozilla/dom/Element.h" #include "nsIContent.h" namespace mozilla { /** * AutoConnectedAncestorTracker is a struct which keeps referring the connected * and closest ancestor of a content node. E.g., say, there are nodes are: * Document -> -> ->
and starts tracking it with the
, * and the is removed, this refers the with mConnectedAncestor. * Note that even after reconnected the , this won't refer the
as * connected one. */ struct MOZ_STACK_CLASS AutoConnectedAncestorTracker final { explicit AutoConnectedAncestorTracker(nsIContent& aContent) : mContent(aContent), mPresShell(aContent.IsInComposedDoc() ? aContent.OwnerDoc()->GetPresShell() : nullptr) { if (mPresShell) { mPresShell->AddConnectedAncestorTracker(*this); } } ~AutoConnectedAncestorTracker() { if (mPresShell) { mPresShell->RemoveConnectedAncestorTracker(*this); } } [[nodiscard]] bool ContentWasRemoved() const { return mPresShell && mConnectedAncestor; } [[nodiscard]] dom::Element* GetConnectedElement() const { return ContentWasRemoved() ? mConnectedAncestor->GetAsElementOrParentElement() : mContent->GetAsElementOrParentElement(); } [[nodiscard]] nsIContent* GetConnectedContent() const { return ContentWasRemoved() ? nsIContent::FromNode(mConnectedAncestor) : mContent.get(); } [[nodiscard]] nsINode& ConnectedNode() const { return ContentWasRemoved() ? *mConnectedAncestor : mContent.ref(); } // Store the original content node. const OwningNonNull mContent; // Store the connected ancestor node if and only if mContent has been deleted // from the document. nsCOMPtr mConnectedAncestor; // The PresShell which manages this instance. const RefPtr mPresShell; AutoConnectedAncestorTracker* mPreviousTracker = nullptr; }; } // namespace mozilla #endif // #ifndef mozilla_ConnectedAncestorTracker_h