Issue #1118 - Part 5: Change the way document.open() works

This changes the work we do for document.open() in the following ways:
- We no longer create a new Window when doing document.open().
  We use the same Window but remove all the event listeners on the
  existing DOM tree and Window before removing the document's existing
  children to provide a clean slate document to use for .write().
- We no longer create a session history entry (previously would be a
  wyciwyg URI). We now replace the current one, effectively losing the
  entry for the original document.
- We now support document.open() on windowless documents.

1 files changed, 71 insertions, 0 deletions

diff --git a/dom/base/SimpleTreeIterator.h b/dom/base/SimpleTreeIterator.h
new file mode 100644
index 0000000000..7ca5040828
--- /dev/null
+++ b/dom/base/SimpleTreeIterator.h
@@ -0,0 +1,71 @@
+/* -*- 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/. */
+
+/**
+ * This is a light-weight tree iterator for `for` loops when full iterator
+ * functionality isn't required.
+ */
+
+#ifndef mozilla_dom_SimpleTreeIterator_h
+#define mozilla_dom_SimpleTreeIterator_h
+
+#include "nsINode.h"
+#include "nsTArray.h"
+#include "mozilla/dom/Element.h"
+
+namespace mozilla {
+namespace dom {
+
+class SimpleTreeIterator {
+public:
+  /**
+   * Initialize an iterator with aRoot. After that it can be iterated with a
+   * range-based for loop. At the moment, that's the only supported form of use
+   * for this iterator.
+   */
+  explicit SimpleTreeIterator(nsINode& aRoot)
+    : mCurrent(&aRoot)
+  {
+    mTree.AppendElement(&aRoot);
+  }
+
+  // Basic support for range-based for loops.
+  // This will modify the iterator as it goes.
+  SimpleTreeIterator& begin() { return *this; }
+
+  SimpleTreeIterator end() { return SimpleTreeIterator(); }
+
+  bool operator!=(const SimpleTreeIterator& aOther) {
+    return mCurrent != aOther.mCurrent;
+  }
+
+  void operator++() { Next(); }
+
+  nsINode* operator*() { return mCurrent; }
+
+private:
+  // Constructor used only for end() to represent a drained iterator.
+  SimpleTreeIterator()
+    : mCurrent(nullptr)
+  {}
+
+  void Next() {
+    MOZ_ASSERT(mCurrent, "Don't call Next() when we have no current node");
+
+    mCurrent = mCurrent->GetNextNode(mTree.LastElement());
+  }
+
+  // The current node.
+  nsINode* mCurrent;
+
+  // The DOM tree that we're inside of right now.
+  AutoTArray<nsINode*, 1> mTree;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_SimpleTreeIterator_h