1 files changed, 66 insertions, 0 deletions
diff --git a/dom/base/nsTraversal.cpp b/dom/base/nsTraversal.cpp
new file mode 100644
index 0000000000..33582a5e8d
--- /dev/null
+++ b/dom/base/nsTraversal.cpp
@@ -0,0 +1,66 @@
+/* -*- 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/. */
+
+#include "nsTraversal.h"
+
+#include "nsError.h"
+#include "nsINode.h"
+#include "mozilla/AutoRestore.h"
+#include "mozilla/dom/NodeFilterBinding.h"
+
+#include "nsGkAtoms.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+nsTraversal::nsTraversal(nsINode* aRoot, uint32_t aWhatToShow,
+                         NodeFilter* aFilter)
+    : mRoot(aRoot),
+      mWhatToShow(aWhatToShow),
+      mFilter(aFilter),
+      mInAcceptNode(false) {
+  NS_ASSERTION(aRoot, "invalid root in call to nsTraversal constructor");
+}
+
+nsTraversal::~nsTraversal() { /* destructor code */
+}
+
+/*
+ * Tests if and how a node should be filtered. Uses mWhatToShow and
+ * mFilter to test the node.
+ * @param aNode     Node to test
+ * @param aResult   Whether we succeeded
+ * @returns         Filtervalue. See NodeFilter.webidl
+ */
+int16_t nsTraversal::TestNode(nsINode* aNode, mozilla::ErrorResult& aResult,
+                              nsCOMPtr<nsINode>* aUnskippedNode) {
+  if (mInAcceptNode) {
+    aResult.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
+    return 0;
+  }
+
+  uint16_t nodeType = aNode->NodeType();
+
+  if (nodeType <= 12 && !((1 << (nodeType - 1)) & mWhatToShow)) {
+    return NodeFilter_Binding::FILTER_SKIP;
+  }
+
+  if (aUnskippedNode) {
+    *aUnskippedNode = aNode;
+  }
+
+  if (!mFilter) {
+    // No filter, just accept
+    return NodeFilter_Binding::FILTER_ACCEPT;
+  }
+
+  AutoRestore<bool> inAcceptNode(mInAcceptNode);
+  mInAcceptNode = true;
+  // No need to pass in an execution reason, since the generated default,
+  // "NodeFilter.acceptNode", is pretty much exactly what we'd say anyway.
+  return mFilter->AcceptNode(*aNode, aResult, nullptr,
+                             CallbackObject::eRethrowExceptions);
+}