1 files changed, 83 insertions, 0 deletions
diff --git a/dom/base/NodeIterator.h b/dom/base/NodeIterator.h
new file mode 100644
index 0000000000..0f20734685
--- /dev/null
+++ b/dom/base/NodeIterator.h
@@ -0,0 +1,83 @@
+/* -*- Mode: C++; tab-width: 4; 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/. */
+
+/*
+ * Implementation of DOM Traversal's NodeIterator
+ */
+
+#ifndef mozilla_dom_NodeIterator_h
+#define mozilla_dom_NodeIterator_h
+
+#include "nsTraversal.h"
+#include "nsCycleCollectionParticipant.h"
+#include "nsStubMutationObserver.h"
+
+class nsINode;
+
+namespace mozilla::dom {
+
+class NodeIterator final : public nsStubMutationObserver, public nsTraversal {
+ public:
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+
+  NodeIterator(nsINode* aRoot, uint32_t aWhatToShow, NodeFilter* aFilter);
+
+  NS_DECL_NSIMUTATIONOBSERVER_CONTENTREMOVED
+
+  NS_DECL_CYCLE_COLLECTION_CLASS(NodeIterator)
+
+  // WebIDL API
+  nsINode* Root() const { return mRoot; }
+  nsINode* GetReferenceNode() const { return mPointer.mNode; }
+  bool PointerBeforeReferenceNode() const { return mPointer.mBeforeNode; }
+  uint32_t WhatToShow() const { return mWhatToShow; }
+  NodeFilter* GetFilter() { return mFilter; }
+  already_AddRefed<nsINode> NextNode(ErrorResult& aResult) {
+    return NextOrPrevNode(&NodePointer::MoveToNext, aResult);
+  }
+  already_AddRefed<nsINode> PreviousNode(ErrorResult& aResult) {
+    return NextOrPrevNode(&NodePointer::MoveToPrevious, aResult);
+  }
+  void Detach();
+
+  bool WrapObject(JSContext* cx, JS::Handle<JSObject*> aGivenProto,
+                  JS::MutableHandle<JSObject*> aReflector);
+
+ private:
+  virtual ~NodeIterator();
+
+  struct NodePointer {
+    NodePointer() : mNode(nullptr), mBeforeNode(false) {}
+    NodePointer(nsINode* aNode, bool aBeforeNode);
+
+    typedef bool (NodePointer::*MoveToMethodType)(nsINode*);
+    bool MoveToNext(nsINode* aRoot);
+    bool MoveToPrevious(nsINode* aRoot);
+
+    bool MoveForward(nsINode* aRoot, nsINode* aNode);
+    void MoveBackward(nsINode* aParent, nsINode* aNode);
+
+    void AdjustAfterRemoval(nsINode* aRoot, nsINode* aContainer,
+                            nsIContent* aChild, nsIContent* aPreviousSibling);
+
+    void Clear() { mNode = nullptr; }
+
+    nsINode* mNode;
+    bool mBeforeNode;
+  };
+
+  // Have to return a strong ref, because the act of testing the node can
+  // remove it from the DOM so we're holding the only ref to it.
+  already_AddRefed<nsINode> NextOrPrevNode(NodePointer::MoveToMethodType aMove,
+                                           ErrorResult& aResult);
+
+  NodePointer mPointer;
+  NodePointer mWorkingPointer;
+};
+
+}  // namespace mozilla::dom
+
+#endif  // mozilla_dom_NodeIterator_h