Adding upstream version 115.7.0esr.upstream/115.7.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1140 insertions, 0 deletions

diff --git a/editor/libeditor/TextEditor.cpp b/editor/libeditor/TextEditor.cpp
new file mode 100644
index 0000000000..d5901850ad
--- /dev/null
+++ b/editor/libeditor/TextEditor.cpp
@@ -0,0 +1,1140 @@
+/* -*- 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/. */
+
+#include "TextEditor.h"
+
+#include <algorithm>
+
+#include "EditAction.h"
+#include "EditAggregateTransaction.h"
+#include "EditorDOMPoint.h"
+#include "HTMLEditor.h"
+#include "HTMLEditUtils.h"
+#include "InternetCiter.h"
+#include "PlaceholderTransaction.h"
+#include "gfxFontUtils.h"
+
+#include "mozilla/dom/DocumentInlines.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/ContentIterator.h"
+#include "mozilla/IMEStateManager.h"
+#include "mozilla/LookAndFeel.h"
+#include "mozilla/mozalloc.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/PresShell.h"
+#include "mozilla/StaticPrefs_editor.h"
+#include "mozilla/TextComposition.h"
+#include "mozilla/TextEvents.h"
+#include "mozilla/TextServicesDocument.h"
+#include "mozilla/dom/Event.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/Selection.h"
+#include "mozilla/dom/StaticRange.h"
+
+#include "nsAString.h"
+#include "nsCRT.h"
+#include "nsCaret.h"
+#include "nsCharTraits.h"
+#include "nsComponentManagerUtils.h"
+#include "nsContentCID.h"
+#include "nsContentList.h"
+#include "nsDebug.h"
+#include "nsDependentSubstring.h"
+#include "nsError.h"
+#include "nsFocusManager.h"
+#include "nsGkAtoms.h"
+#include "nsIClipboard.h"
+#include "nsIContent.h"
+#include "nsINode.h"
+#include "nsIPrincipal.h"
+#include "nsISelectionController.h"
+#include "nsISupportsPrimitives.h"
+#include "nsITransferable.h"
+#include "nsIWeakReferenceUtils.h"
+#include "nsNameSpaceManager.h"
+#include "nsLiteralString.h"
+#include "nsPresContext.h"
+#include "nsReadableUtils.h"
+#include "nsServiceManagerUtils.h"
+#include "nsString.h"
+#include "nsStringFwd.h"
+#include "nsTextFragment.h"
+#include "nsTextNode.h"
+#include "nsUnicharUtils.h"
+#include "nsXPCOM.h"
+
+class nsIOutputStream;
+class nsISupports;
+
+namespace mozilla {
+
+using namespace dom;
+
+using LeafNodeType = HTMLEditUtils::LeafNodeType;
+using LeafNodeTypes = HTMLEditUtils::LeafNodeTypes;
+
+TextEditor::TextEditor() : EditorBase(EditorBase::EditorType::Text) {
+  // printf("Size of TextEditor: %zu\n", sizeof(TextEditor));
+  static_assert(
+      sizeof(TextEditor) <= 512,
+      "TextEditor instance should be allocatable in the quantum class bins");
+}
+
+TextEditor::~TextEditor() {
+  // Remove event listeners. Note that if we had an HTML editor,
+  //  it installed its own instead of these
+  RemoveEventListeners();
+}
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(TextEditor)
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(TextEditor, EditorBase)
+  if (tmp->mPasswordMaskData) {
+    tmp->mPasswordMaskData->CancelTimer(PasswordMaskData::ReleaseTimer::No);
+    NS_IMPL_CYCLE_COLLECTION_UNLINK(mPasswordMaskData->mTimer)
+  }
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(TextEditor, EditorBase)
+  if (tmp->mPasswordMaskData) {
+    NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPasswordMaskData->mTimer)
+  }
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_ADDREF_INHERITED(TextEditor, EditorBase)
+NS_IMPL_RELEASE_INHERITED(TextEditor, EditorBase)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(TextEditor)
+  NS_INTERFACE_MAP_ENTRY(nsITimerCallback)
+  NS_INTERFACE_MAP_ENTRY(nsINamed)
+NS_INTERFACE_MAP_END_INHERITING(EditorBase)
+
+NS_IMETHODIMP TextEditor::EndOfDocument() {
+  AutoEditActionDataSetter editActionData(*this, EditAction::eNotEditing);
+  if (NS_WARN_IF(!editActionData.CanHandle())) {
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+  nsresult rv = CollapseSelectionToEndOfTextNode();
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "TextEditor::CollapseSelectionToEndOfTextNode() failed");
+  // This is low level API for embedders and chrome script so that we can return
+  // raw error code here.
+  return rv;
+}
+
+nsresult TextEditor::CollapseSelectionToEndOfTextNode() {
+  MOZ_ASSERT(IsEditActionDataAvailable());
+
+  Element* anonymousDivElement = GetRoot();
+  if (NS_WARN_IF(!anonymousDivElement)) {
+    return NS_ERROR_NULL_POINTER;
+  }
+
+  RefPtr<Text> textNode =
+      Text::FromNodeOrNull(anonymousDivElement->GetFirstChild());
+  MOZ_ASSERT(textNode);
+  nsresult rv = CollapseSelectionToEndOf(*textNode);
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "EditorBase::CollapseSelectionToEndOf() failed");
+  return rv;
+}
+
+nsresult TextEditor::Init(Document& aDocument, Element& aAnonymousDivElement,
+                          nsISelectionController& aSelectionController,
+                          uint32_t aFlags,
+                          UniquePtr<PasswordMaskData>&& aPasswordMaskData) {
+  MOZ_ASSERT(!mInitSucceeded,
+             "TextEditor::Init() called again without calling PreDestroy()?");
+  MOZ_ASSERT(!(aFlags & nsIEditor::eEditorPasswordMask) == !aPasswordMaskData);
+  mPasswordMaskData = std::move(aPasswordMaskData);
+
+  // Init the base editor
+  nsresult rv = InitInternal(aDocument, &aAnonymousDivElement,
+                             aSelectionController, aFlags);
+  if (NS_FAILED(rv)) {
+    NS_WARNING("EditorBase::InitInternal() failed");
+    return rv;
+  }
+
+  AutoEditActionDataSetter editActionData(*this, EditAction::eInitializing);
+  if (NS_WARN_IF(!editActionData.CanHandle())) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // We set mInitSucceeded here rather than at the end of the function,
+  // since InitEditorContentAndSelection() can perform some transactions
+  // and can warn if mInitSucceeded is still false.
+  MOZ_ASSERT(!mInitSucceeded, "TextEditor::Init() shouldn't be nested");
+  mInitSucceeded = true;
+
+  rv = InitEditorContentAndSelection();
+  if (NS_FAILED(rv)) {
+    NS_WARNING("TextEditor::InitEditorContentAndSelection() failed");
+    // XXX Shouldn't we expose `NS_ERROR_EDITOR_DESTROYED` even though this
+    //     is a public method?
+    mInitSucceeded = false;
+    return EditorBase::ToGenericNSResult(rv);
+  }
+
+  // Throw away the old transaction manager if this is not the first time that
+  // we're initializing the editor.
+  ClearUndoRedo();
+  EnableUndoRedo();
+  return NS_OK;
+}
+
+nsresult TextEditor::InitEditorContentAndSelection() {
+  MOZ_ASSERT(IsEditActionDataAvailable());
+
+  MOZ_TRY(EnsureEmptyTextFirstChild());
+
+  // If the selection hasn't been set up yet, set it up collapsed to the end of
+  // our editable content.
+  if (!SelectionRef().RangeCount()) {
+    nsresult rv = CollapseSelectionToEndOfTextNode();
+    if (NS_FAILED(rv)) {
+      NS_WARNING("EditorBase::CollapseSelectionToEndOfTextNode() failed");
+      return rv;
+    }
+  }
+
+  if (!IsSingleLineEditor()) {
+    nsresult rv = EnsurePaddingBRElementInMultilineEditor();
+    if (NS_FAILED(rv)) {
+      NS_WARNING(
+          "EditorBase::EnsurePaddingBRElementInMultilineEditor() failed");
+      return rv;
+    }
+  }
+
+  return NS_OK;
+}
+
+nsresult TextEditor::PostCreate() {
+  AutoEditActionDataSetter editActionData(*this, EditAction::eNotEditing);
+  if (NS_WARN_IF(!editActionData.CanHandle())) {
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+
+  nsresult rv = PostCreateInternal();
+
+  // Restore unmasked range if there is.
+  if (IsPasswordEditor() && !IsAllMasked()) {
+    DebugOnly<nsresult> rvIgnored =
+        SetUnmaskRangeAndNotify(UnmaskedStart(), UnmaskedLength());
+    NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                         "TextEditor::SetUnmaskRangeAndNotify() failed to "
+                         "restore unmasked range, but ignored");
+  }
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "EditorBase::PostCreateInternal() failed");
+  return rv;
+}
+
+UniquePtr<PasswordMaskData> TextEditor::PreDestroy() {
+  if (mDidPreDestroy) {
+    return nullptr;
+  }
+
+  UniquePtr<PasswordMaskData> passwordMaskData = std::move(mPasswordMaskData);
+  if (passwordMaskData) {
+    // Disable auto-masking timer since nobody can catch the notification
+    // from the timer and canceling the unmasking.
+    passwordMaskData->CancelTimer(PasswordMaskData::ReleaseTimer::Yes);
+    // Similary, keeping preventing echoing password temporarily across
+    // TextEditor instances is hard.  So, we should forget it.
+    passwordMaskData->mEchoingPasswordPrevented = false;
+  }
+
+  PreDestroyInternal();
+
+  return passwordMaskData;
+}
+
+nsresult TextEditor::HandleKeyPressEvent(WidgetKeyboardEvent* aKeyboardEvent) {
+  // NOTE: When you change this method, you should also change:
+  //   * editor/libeditor/tests/test_texteditor_keyevent_handling.html
+  //   * editor/libeditor/tests/test_htmleditor_keyevent_handling.html
+  //
+  // And also when you add new key handling, you need to change the subclass's
+  // HandleKeyPressEvent()'s switch statement.
+
+  if (NS_WARN_IF(!aKeyboardEvent)) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  if (IsReadonly()) {
+    HandleKeyPressEventInReadOnlyMode(*aKeyboardEvent);
+    return NS_OK;
+  }
+
+  MOZ_ASSERT(aKeyboardEvent->mMessage == eKeyPress,
+             "HandleKeyPressEvent gets non-keypress event");
+
+  switch (aKeyboardEvent->mKeyCode) {
+    case NS_VK_META:
+    case NS_VK_WIN:
+    case NS_VK_SHIFT:
+    case NS_VK_CONTROL:
+    case NS_VK_ALT:
+      // FYI: This shouldn't occur since modifier key shouldn't cause eKeyPress
+      //      event.
+      aKeyboardEvent->PreventDefault();
+      return NS_OK;
+
+    case NS_VK_BACK:
+    case NS_VK_DELETE:
+    case NS_VK_TAB: {
+      nsresult rv = EditorBase::HandleKeyPressEvent(aKeyboardEvent);
+      NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                           "EditorBase::HandleKeyPressEvent() failed");
+      return rv;
+    }
+    case NS_VK_RETURN: {
+      if (!aKeyboardEvent->IsInputtingLineBreak()) {
+        return NS_OK;
+      }
+      if (!IsSingleLineEditor()) {
+        aKeyboardEvent->PreventDefault();
+      }
+      // We need to dispatch "beforeinput" event at least even if we're a
+      // single line text editor.
+      nsresult rv = InsertLineBreakAsAction();
+      NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                           "TextEditor::InsertLineBreakAsAction() failed");
+      return rv;
+    }
+  }
+
+  if (!aKeyboardEvent->IsInputtingText()) {
+    // we don't PreventDefault() here or keybindings like control-x won't work
+    return NS_OK;
+  }
+  // Our widget shouldn't set `\r` to `mCharCode`, but it may be synthesized
+  // keyboard event and its value may be `\r`.  In such case, we should treat
+  // it as `\n` for the backward compatibility because we stopped converting
+  // `\r` and `\r\n` to `\n` at getting `HTMLInputElement.value` and
+  // `HTMLTextAreaElement.value` for the performance (i.e., we don't need to
+  // take care in `HTMLEditor`).
+  char16_t charCode =
+      static_cast<char16_t>(aKeyboardEvent->mCharCode) == nsCRT::CR
+          ? nsCRT::LF
+          : static_cast<char16_t>(aKeyboardEvent->mCharCode);
+  aKeyboardEvent->PreventDefault();
+  nsAutoString str(charCode);
+  nsresult rv = OnInputText(str);
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "EditorBase::OnInputText() failed");
+  return rv;
+}
+
+NS_IMETHODIMP TextEditor::InsertLineBreak() {
+  AutoEditActionDataSetter editActionData(*this, EditAction::eInsertLineBreak);
+  nsresult rv = editActionData.CanHandleAndMaybeDispatchBeforeInputEvent();
+  if (NS_FAILED(rv)) {
+    NS_WARNING_ASSERTION(rv == NS_ERROR_EDITOR_ACTION_CANCELED,
+                         "CanHandleAndMaybeDispatchBeforeInputEvent() failed");
+    return EditorBase::ToGenericNSResult(rv);
+  }
+
+  if (NS_WARN_IF(IsSingleLineEditor())) {
+    return NS_ERROR_FAILURE;
+  }
+
+  AutoPlaceholderBatch treatAsOneTransaction(
+      *this, ScrollSelectionIntoView::Yes, __FUNCTION__);
+  rv = InsertLineBreakAsSubAction();
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "TextEditor::InsertLineBreakAsSubAction() failed");
+  return EditorBase::ToGenericNSResult(rv);
+}
+
+nsresult TextEditor::InsertLineBreakAsAction(nsIPrincipal* aPrincipal) {
+  AutoEditActionDataSetter editActionData(*this, EditAction::eInsertLineBreak,
+                                          aPrincipal);
+  nsresult rv = editActionData.CanHandleAndMaybeDispatchBeforeInputEvent();
+  if (NS_FAILED(rv)) {
+    NS_WARNING_ASSERTION(rv == NS_ERROR_EDITOR_ACTION_CANCELED,
+                         "CanHandleAndMaybeDispatchBeforeInputEvent() failed");
+    return EditorBase::ToGenericNSResult(rv);
+  }
+
+  if (IsSingleLineEditor()) {
+    return NS_OK;
+  }
+
+  // XXX This may be called by execCommand() with "insertParagraph".
+  //     In such case, naming the transaction "TypingTxnName" is odd.
+  AutoPlaceholderBatch treatAsOneTransaction(*this, *nsGkAtoms::TypingTxnName,
+                                             ScrollSelectionIntoView::Yes,
+                                             __FUNCTION__);
+  rv = InsertLineBreakAsSubAction();
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "EditorBase::InsertLineBreakAsSubAction() failed");
+  return EditorBase::ToGenericNSResult(rv);
+}
+
+nsresult TextEditor::SetTextAsAction(
+    const nsAString& aString,
+    AllowBeforeInputEventCancelable aAllowBeforeInputEventCancelable,
+    nsIPrincipal* aPrincipal) {
+  MOZ_ASSERT(aString.FindChar(nsCRT::CR) == kNotFound);
+
+  AutoEditActionDataSetter editActionData(*this, EditAction::eSetText,
+                                          aPrincipal);
+  if (aAllowBeforeInputEventCancelable == AllowBeforeInputEventCancelable::No) {
+    editActionData.MakeBeforeInputEventNonCancelable();
+  }
+  nsresult rv = editActionData.CanHandleAndMaybeDispatchBeforeInputEvent();
+  if (NS_FAILED(rv)) {
+    NS_WARNING_ASSERTION(rv == NS_ERROR_EDITOR_ACTION_CANCELED,
+                         "CanHandleAndMaybeDispatchBeforeInputEvent() failed");
+    return EditorBase::ToGenericNSResult(rv);
+  }
+
+  AutoPlaceholderBatch treatAsOneTransaction(
+      *this, ScrollSelectionIntoView::Yes, __FUNCTION__);
+  rv = SetTextAsSubAction(aString);
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "TextEditor::SetTextAsSubAction() failed");
+  return EditorBase::ToGenericNSResult(rv);
+}
+
+nsresult TextEditor::SetTextAsSubAction(const nsAString& aString) {
+  MOZ_ASSERT(IsEditActionDataAvailable());
+  MOZ_ASSERT(mPlaceholderBatch);
+
+  if (NS_WARN_IF(!mInitSucceeded)) {
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+
+  IgnoredErrorResult ignoredError;
+  AutoEditSubActionNotifier startToHandleEditSubAction(
+      *this, EditSubAction::eSetText, nsIEditor::eNext, ignoredError);
+  if (NS_WARN_IF(ignoredError.ErrorCodeIs(NS_ERROR_EDITOR_DESTROYED))) {
+    return ignoredError.StealNSResult();
+  }
+  NS_WARNING_ASSERTION(
+      !ignoredError.Failed(),
+      "TextEditor::OnStartToHandleTopLevelEditSubAction() failed, but ignored");
+
+  if (!IsIMEComposing() && !IsUndoRedoEnabled() &&
+      GetEditAction() != EditAction::eReplaceText && mMaxTextLength < 0) {
+    Result<EditActionResult, nsresult> result =
+        SetTextWithoutTransaction(aString);
+    if (MOZ_UNLIKELY(result.isErr())) {
+      NS_WARNING("TextEditor::SetTextWithoutTransaction() failed");
+      return result.unwrapErr();
+    }
+    if (!result.inspect().Ignored()) {
+      return NS_OK;
+    }
+  }
+
+  {
+    // Note that do not notify selectionchange caused by selecting all text
+    // because it's preparation of our delete implementation so web apps
+    // shouldn't receive such selectionchange before the first mutation.
+    AutoUpdateViewBatch preventSelectionChangeEvent(*this, __FUNCTION__);
+
+    // XXX We should make ReplaceSelectionAsSubAction() take range.  Then,
+    //     we can saving the expensive cost of modifying `Selection` here.
+    if (NS_SUCCEEDED(SelectEntireDocument())) {
+      DebugOnly<nsresult> rvIgnored = ReplaceSelectionAsSubAction(aString);
+      NS_WARNING_ASSERTION(
+          NS_SUCCEEDED(rvIgnored),
+          "EditorBase::ReplaceSelectionAsSubAction() failed, but ignored");
+    }
+  }
+
+  // Destroying AutoUpdateViewBatch may cause destroying us.
+  return NS_WARN_IF(Destroyed()) ? NS_ERROR_EDITOR_DESTROYED : NS_OK;
+}
+
+already_AddRefed<Element> TextEditor::GetInputEventTargetElement() const {
+  RefPtr<Element> target = Element::FromEventTargetOrNull(mEventTarget);
+  return target.forget();
+}
+
+bool TextEditor::IsEmpty() const {
+  // Even if there is no padding <br> element for empty editor, we should be
+  // detected as empty editor if all the children are text nodes and these
+  // have no content.
+  Element* anonymousDivElement = GetRoot();
+  if (!anonymousDivElement) {
+    return true;  // Don't warn it, this is possible, e.g., 997805.html
+  }
+
+  MOZ_ASSERT(anonymousDivElement->GetFirstChild() &&
+             anonymousDivElement->GetFirstChild()->IsText());
+
+  // Only when there is non-empty text node, we are not empty.
+  return !anonymousDivElement->GetFirstChild()->Length();
+}
+
+NS_IMETHODIMP TextEditor::GetTextLength(uint32_t* aCount) {
+  MOZ_ASSERT(aCount);
+
+  // initialize out params
+  *aCount = 0;
+
+  // special-case for empty document, to account for the padding <br> element
+  // for empty editor.
+  // XXX This should be overridden by `HTMLEditor` and we should return the
+  //     first text node's length from `TextEditor` instead.  The following
+  //     code is too expensive.
+  if (IsEmpty()) {
+    return NS_OK;
+  }
+
+  Element* rootElement = GetRoot();
+  if (NS_WARN_IF(!rootElement)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  uint32_t totalLength = 0;
+  PostContentIterator postOrderIter;
+  DebugOnly<nsresult> rvIgnored = postOrderIter.Init(rootElement);
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                       "PostContentIterator::Init() failed, but ignored");
+  EditorType editorType = GetEditorType();
+  for (; !postOrderIter.IsDone(); postOrderIter.Next()) {
+    nsINode* currentNode = postOrderIter.GetCurrentNode();
+    if (currentNode && currentNode->IsText() &&
+        EditorUtils::IsEditableContent(*currentNode->AsText(), editorType)) {
+      totalLength += currentNode->Length();
+    }
+  }
+
+  *aCount = totalLength;
+  return NS_OK;
+}
+
+bool TextEditor::IsCopyToClipboardAllowedInternal() const {
+  MOZ_ASSERT(IsEditActionDataAvailable());
+  if (!EditorBase::IsCopyToClipboardAllowedInternal()) {
+    return false;
+  }
+
+  if (!IsSingleLineEditor() || !IsPasswordEditor() ||
+      NS_WARN_IF(!mPasswordMaskData)) {
+    return true;
+  }
+
+  // If we're a password editor, we should allow selected text to be copied
+  // to the clipboard only when selection range is in unmasked range.
+  if (IsAllMasked() || IsMaskingPassword() || !UnmaskedLength()) {
+    return false;
+  }
+
+  // If there are 2 or more ranges, we don't allow to copy/cut for now since
+  // we need to check whether all ranges are in unmasked range or not.
+  // Anyway, such operation in password field does not make sense.
+  if (SelectionRef().RangeCount() > 1) {
+    return false;
+  }
+
+  uint32_t selectionStart = 0, selectionEnd = 0;
+  nsContentUtils::GetSelectionInTextControl(&SelectionRef(), mRootElement,
+                                            selectionStart, selectionEnd);
+  return UnmaskedStart() <= selectionStart && UnmaskedEnd() >= selectionEnd;
+}
+
+nsresult TextEditor::HandlePasteAsQuotation(
+    AutoEditActionDataSetter& aEditActionData, int32_t aClipboardType) {
+  MOZ_ASSERT(aClipboardType == nsIClipboard::kGlobalClipboard ||
+             aClipboardType == nsIClipboard::kSelectionClipboard);
+  if (NS_WARN_IF(!GetDocument())) {
+    return NS_OK;
+  }
+
+  // Get Clipboard Service
+  nsresult rv;
+  nsCOMPtr<nsIClipboard> clipboard =
+      do_GetService("@mozilla.org/widget/clipboard;1", &rv);
+  if (NS_FAILED(rv)) {
+    NS_WARNING("Failed to get nsIClipboard service");
+    return rv;
+  }
+
+  // XXX Why don't we dispatch ePaste event here?
+
+  // Get the nsITransferable interface for getting the data from the clipboard
+  Result<nsCOMPtr<nsITransferable>, nsresult> maybeTransferable =
+      EditorUtils::CreateTransferableForPlainText(*GetDocument());
+  if (maybeTransferable.isErr()) {
+    NS_WARNING("EditorUtils::CreateTransferableForPlainText() failed");
+    return maybeTransferable.unwrapErr();
+  }
+  nsCOMPtr<nsITransferable> trans(maybeTransferable.unwrap());
+  if (!trans) {
+    NS_WARNING(
+        "EditorUtils::CreateTransferableForPlainText() returned nullptr, but "
+        "ignored");
+    return NS_OK;
+  }
+
+  // Get the Data from the clipboard
+  clipboard->GetData(trans, aClipboardType);
+
+  // Now we ask the transferable for the data
+  // it still owns the data, we just have a pointer to it.
+  // If it can't support a "text" output of the data the call will fail
+  nsCOMPtr<nsISupports> genericDataObj;
+  nsAutoCString flavor;
+  rv = trans->GetAnyTransferData(flavor, getter_AddRefs(genericDataObj));
+  if (NS_FAILED(rv)) {
+    NS_WARNING("nsITransferable::GetAnyTransferData() failed");
+    return rv;
+  }
+
+  if (!flavor.EqualsLiteral(kTextMime) &&
+      !flavor.EqualsLiteral(kMozTextInternal)) {
+    return NS_OK;
+  }
+
+  nsCOMPtr<nsISupportsString> text = do_QueryInterface(genericDataObj);
+  if (!text) {
+    return NS_OK;
+  }
+
+  nsString stuffToPaste;
+  DebugOnly<nsresult> rvIgnored = text->GetData(stuffToPaste);
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                       "nsISupportsString::GetData() failed, but ignored");
+  if (stuffToPaste.IsEmpty()) {
+    return NS_OK;
+  }
+
+  aEditActionData.SetData(stuffToPaste);
+  if (!stuffToPaste.IsEmpty()) {
+    nsContentUtils::PlatformToDOMLineBreaks(stuffToPaste);
+  }
+  rv = aEditActionData.MaybeDispatchBeforeInputEvent();
+  if (NS_FAILED(rv)) {
+    NS_WARNING_ASSERTION(rv == NS_ERROR_EDITOR_ACTION_CANCELED,
+                         "MaybeDispatchBeforeInputEvent() failed");
+    return rv;
+  }
+
+  AutoPlaceholderBatch treatAsOneTransaction(
+      *this, ScrollSelectionIntoView::Yes, __FUNCTION__);
+  rv = InsertWithQuotationsAsSubAction(stuffToPaste);
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "TextEditor::InsertWithQuotationsAsSubAction() failed");
+  return rv;
+}
+
+nsresult TextEditor::InsertWithQuotationsAsSubAction(
+    const nsAString& aQuotedText) {
+  MOZ_ASSERT(IsEditActionDataAvailable());
+
+  if (IsReadonly()) {
+    return NS_OK;
+  }
+
+  // Let the citer quote it for us:
+  nsString quotedStuff;
+  InternetCiter::GetCiteString(aQuotedText, quotedStuff);
+
+  // It's best to put a blank line after the quoted text so that mails
+  // written without thinking won't be so ugly.
+  if (!aQuotedText.IsEmpty() && (aQuotedText.Last() != char16_t('\n'))) {
+    quotedStuff.Append(char16_t('\n'));
+  }
+
+  IgnoredErrorResult ignoredError;
+  AutoEditSubActionNotifier startToHandleEditSubAction(
+      *this, EditSubAction::eInsertText, nsIEditor::eNext, ignoredError);
+  if (NS_WARN_IF(ignoredError.ErrorCodeIs(NS_ERROR_EDITOR_DESTROYED))) {
+    return ignoredError.StealNSResult();
+  }
+  NS_WARNING_ASSERTION(
+      !ignoredError.Failed(),
+      "TextEditor::OnStartToHandleTopLevelEditSubAction() failed, but ignored");
+
+  // XXX Do we need to support paste-as-quotation in password editor (and
+  //     also in single line editor)?
+  MaybeDoAutoPasswordMasking();
+
+  nsresult rv = InsertTextAsSubAction(quotedStuff, SelectionHandling::Delete);
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "EditorBase::InsertTextAsSubAction() failed");
+  return rv;
+}
+
+nsresult TextEditor::SelectEntireDocument() {
+  MOZ_ASSERT(IsEditActionDataAvailable());
+
+  if (NS_WARN_IF(!mInitSucceeded)) {
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+
+  RefPtr<Element> anonymousDivElement = GetRoot();
+  if (NS_WARN_IF(!anonymousDivElement)) {
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+
+  RefPtr<Text> text =
+      Text::FromNodeOrNull(anonymousDivElement->GetFirstChild());
+  MOZ_ASSERT(text);
+
+  MOZ_TRY(SelectionRef().SetStartAndEndInLimiter(
+      *text, 0, *text, text->TextDataLength(), eDirNext,
+      nsISelectionListener::SELECTALL_REASON));
+
+  return NS_OK;
+}
+
+EventTarget* TextEditor::GetDOMEventTarget() const { return mEventTarget; }
+
+void TextEditor::ReinitializeSelection(Element& aElement) {
+  if (NS_WARN_IF(Destroyed())) {
+    return;
+  }
+
+  AutoEditActionDataSetter editActionData(*this, EditAction::eNotEditing);
+  if (NS_WARN_IF(!editActionData.CanHandle())) {
+    return;
+  }
+
+  // We don't need to flush pending notifications here and we don't need to
+  // handle spellcheck at first focus.  Therefore, we don't need to call
+  // `TextEditor::OnFocus` here.
+  EditorBase::OnFocus(aElement);
+
+  // If previous focused editor turn on spellcheck and this editor doesn't
+  // turn on it, spellcheck state is mismatched.  So we need to re-sync it.
+  SyncRealTimeSpell();
+}
+
+nsresult TextEditor::OnFocus(const nsINode& aOriginalEventTargetNode) {
+  RefPtr<PresShell> presShell = GetPresShell();
+  if (NS_WARN_IF(!presShell)) {
+    return NS_ERROR_FAILURE;
+  }
+  // Let's update the layout information right now because there are some
+  // pending notifications and flushing them may cause destroying the editor.
+  presShell->FlushPendingNotifications(FlushType::Layout);
+  if (MOZ_UNLIKELY(!CanKeepHandlingFocusEvent(aOriginalEventTargetNode))) {
+    return NS_OK;
+  }
+
+  AutoEditActionDataSetter editActionData(*this, EditAction::eNotEditing);
+  if (NS_WARN_IF(!editActionData.CanHandle())) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // Spell check a textarea the first time that it is focused.
+  nsresult rv = FlushPendingSpellCheck();
+  if (MOZ_UNLIKELY(rv == NS_ERROR_EDITOR_DESTROYED)) {
+    NS_WARNING("EditorBase::FlushPendingSpellCheck() failed");
+    return NS_ERROR_EDITOR_DESTROYED;
+  }
+  NS_WARNING_ASSERTION(
+      NS_SUCCEEDED(rv),
+      "EditorBase::FlushPendingSpellCheck() failed, but ignored");
+  if (MOZ_UNLIKELY(!CanKeepHandlingFocusEvent(aOriginalEventTargetNode))) {
+    return NS_OK;
+  }
+
+  return EditorBase::OnFocus(aOriginalEventTargetNode);
+}
+
+nsresult TextEditor::OnBlur(const EventTarget* aEventTarget) {
+  // check if something else is focused. If another element is focused, then
+  // we should not change the selection.
+  nsFocusManager* focusManager = nsFocusManager::GetFocusManager();
+  if (MOZ_UNLIKELY(!focusManager)) {
+    return NS_OK;
+  }
+
+  // If another element already has focus, we should not maintain the selection
+  // because we may not have the rights doing it.
+  if (focusManager->GetFocusedElement()) {
+    return NS_OK;
+  }
+
+  nsresult rv = FinalizeSelection();
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "EditorBase::FinalizeSelection() failed");
+  return rv;
+}
+
+nsresult TextEditor::SetAttributeOrEquivalent(Element* aElement,
+                                              nsAtom* aAttribute,
+                                              const nsAString& aValue,
+                                              bool aSuppressTransaction) {
+  if (NS_WARN_IF(!aElement) || NS_WARN_IF(!aAttribute)) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  AutoEditActionDataSetter editActionData(*this, EditAction::eSetAttribute);
+  nsresult rv = editActionData.CanHandleAndMaybeDispatchBeforeInputEvent();
+  if (NS_FAILED(rv)) {
+    NS_WARNING_ASSERTION(rv == NS_ERROR_EDITOR_ACTION_CANCELED,
+                         "CanHandleAndMaybeDispatchBeforeInputEvent() failed");
+    return EditorBase::ToGenericNSResult(rv);
+  }
+
+  rv = SetAttributeWithTransaction(*aElement, *aAttribute, aValue);
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "EditorBase::SetAttributeWithTransaction() failed");
+  return EditorBase::ToGenericNSResult(rv);
+}
+
+nsresult TextEditor::RemoveAttributeOrEquivalent(Element* aElement,
+                                                 nsAtom* aAttribute,
+                                                 bool aSuppressTransaction) {
+  if (NS_WARN_IF(!aElement) || NS_WARN_IF(!aAttribute)) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  AutoEditActionDataSetter editActionData(*this, EditAction::eRemoveAttribute);
+  nsresult rv = editActionData.CanHandleAndMaybeDispatchBeforeInputEvent();
+  if (NS_FAILED(rv)) {
+    NS_WARNING_ASSERTION(rv == NS_ERROR_EDITOR_ACTION_CANCELED,
+                         "CanHandleAndMaybeDispatchBeforeInputEvent() failed");
+    return EditorBase::ToGenericNSResult(rv);
+  }
+
+  rv = RemoveAttributeWithTransaction(*aElement, *aAttribute);
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "EditorBase::RemoveAttributeWithTransaction() failed");
+  return EditorBase::ToGenericNSResult(rv);
+}
+
+// static
+void TextEditor::MaskString(nsString& aString, const Text& aTextNode,
+                            uint32_t aStartOffsetInString,
+                            uint32_t aStartOffsetInText) {
+  MOZ_ASSERT(aTextNode.HasFlag(NS_MAYBE_MASKED));
+  MOZ_ASSERT(aStartOffsetInString == 0 || aStartOffsetInText == 0);
+
+  uint32_t unmaskStart = UINT32_MAX, unmaskLength = 0;
+  TextEditor* textEditor =
+      nsContentUtils::GetTextEditorFromAnonymousNodeWithoutCreation(&aTextNode);
+  if (textEditor && textEditor->UnmaskedLength() > 0) {
+    unmaskStart = textEditor->UnmaskedStart();
+    unmaskLength = textEditor->UnmaskedLength();
+    // If text is copied from after unmasked range, we can treat this case
+    // as mask all.
+    if (aStartOffsetInText >= unmaskStart + unmaskLength) {
+      unmaskLength = 0;
+      unmaskStart = UINT32_MAX;
+    } else {
+      // If text is copied from middle of unmasked range, reduce the length
+      // and adjust start offset.
+      if (aStartOffsetInText > unmaskStart) {
+        unmaskLength = unmaskStart + unmaskLength - aStartOffsetInText;
+        unmaskStart = 0;
+      }
+      // If text is copied from before start of unmasked range, just adjust
+      // the start offset.
+      else {
+        unmaskStart -= aStartOffsetInText;
+      }
+      // Make the range is in the string.
+      unmaskStart += aStartOffsetInString;
+    }
+  }
+
+  const char16_t kPasswordMask = TextEditor::PasswordMask();
+  for (uint32_t i = aStartOffsetInString; i < aString.Length(); ++i) {
+    bool isSurrogatePair = NS_IS_HIGH_SURROGATE(aString.CharAt(i)) &&
+                           i < aString.Length() - 1 &&
+                           NS_IS_LOW_SURROGATE(aString.CharAt(i + 1));
+    if (i < unmaskStart || i >= unmaskStart + unmaskLength) {
+      if (isSurrogatePair) {
+        aString.SetCharAt(kPasswordMask, i);
+        aString.SetCharAt(kPasswordMask, i + 1);
+      } else {
+        aString.SetCharAt(kPasswordMask, i);
+      }
+    }
+
+    // Skip the following low surrogate.
+    if (isSurrogatePair) {
+      ++i;
+    }
+  }
+}
+
+nsresult TextEditor::SetUnmaskRangeInternal(uint32_t aStart, uint32_t aLength,
+                                            uint32_t aTimeout, bool aNotify,
+                                            bool aForceStartMasking) {
+  if (mPasswordMaskData) {
+    mPasswordMaskData->mIsMaskingPassword = aForceStartMasking || aTimeout != 0;
+
+    // We cannot manage multiple unmasked ranges so that shrink the previous
+    // range first.
+    if (!IsAllMasked()) {
+      mPasswordMaskData->mUnmaskedLength = 0;
+      mPasswordMaskData->CancelTimer(PasswordMaskData::ReleaseTimer::No);
+    }
+  }
+
+  // If we're not a password editor, return error since this call does not
+  // make sense.
+  if (!IsPasswordEditor() || NS_WARN_IF(!mPasswordMaskData)) {
+    mPasswordMaskData->CancelTimer(PasswordMaskData::ReleaseTimer::Yes);
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+
+  Element* rootElement = GetRoot();
+  if (NS_WARN_IF(!rootElement)) {
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+  Text* text = Text::FromNodeOrNull(rootElement->GetFirstChild());
+  if (!text || !text->Length()) {
+    // There is no anonymous text node in the editor.
+    return aStart > 0 && aStart != UINT32_MAX ? NS_ERROR_INVALID_ARG : NS_OK;
+  }
+
+  if (aStart < UINT32_MAX) {
+    uint32_t valueLength = text->Length();
+    if (aStart >= valueLength) {
+      return NS_ERROR_INVALID_ARG;  // There is no character can be masked.
+    }
+    // If aStart is middle of a surrogate pair, expand it to include the
+    // preceding high surrogate because the caller may want to show a
+    // character before the character at `aStart + 1`.
+    const nsTextFragment* textFragment = text->GetText();
+    if (textFragment->IsLowSurrogateFollowingHighSurrogateAt(aStart)) {
+      mPasswordMaskData->mUnmaskedStart = aStart - 1;
+      // If caller collapses the range, keep it.  Otherwise, expand the length.
+      if (aLength > 0) {
+        ++aLength;
+      }
+    } else {
+      mPasswordMaskData->mUnmaskedStart = aStart;
+    }
+    mPasswordMaskData->mUnmaskedLength =
+        std::min(valueLength - UnmaskedStart(), aLength);
+    // If unmasked end is middle of a surrogate pair, expand it to include
+    // the following low surrogate because the caller may want to show a
+    // character after the character at `aStart + aLength`.
+    if (UnmaskedEnd() < valueLength &&
+        textFragment->IsLowSurrogateFollowingHighSurrogateAt(UnmaskedEnd())) {
+      mPasswordMaskData->mUnmaskedLength++;
+    }
+    // If it's first time to mask the unmasking characters with timer, create
+    // the timer now.  Then, we'll keep using it for saving the creation cost.
+    if (!HasAutoMaskingTimer() && aLength && aTimeout && UnmaskedLength()) {
+      mPasswordMaskData->mTimer = NS_NewTimer();
+    }
+  } else {
+    if (NS_WARN_IF(aLength != 0)) {
+      return NS_ERROR_INVALID_ARG;
+    }
+    mPasswordMaskData->MaskAll();
+  }
+
+  // Notify nsTextFrame of this update if the caller wants this to do it.
+  // Only in this case, script may run.
+  if (aNotify) {
+    MOZ_ASSERT(IsEditActionDataAvailable());
+
+    RefPtr<Document> document = GetDocument();
+    if (NS_WARN_IF(!document)) {
+      return NS_ERROR_NOT_INITIALIZED;
+    }
+    // Notify nsTextFrame of masking range change.
+    if (RefPtr<PresShell> presShell = document->GetObservingPresShell()) {
+      nsAutoScriptBlocker blockRunningScript;
+      uint32_t valueLength = text->Length();
+      CharacterDataChangeInfo changeInfo = {false, 0, valueLength, valueLength,
+                                            nullptr};
+      presShell->CharacterDataChanged(text, changeInfo);
+    }
+
+    // Scroll caret into the view since masking or unmasking character may
+    // move caret to outside of the view.
+    nsresult rv = ScrollSelectionFocusIntoView();
+    if (NS_FAILED(rv)) {
+      NS_WARNING("EditorBase::ScrollSelectionFocusIntoView() failed");
+      return rv;
+    }
+  }
+
+  if (!IsAllMasked() && aTimeout != 0) {
+    // Initialize the timer to mask the range automatically.
+    MOZ_ASSERT(HasAutoMaskingTimer());
+    DebugOnly<nsresult> rvIgnored = mPasswordMaskData->mTimer->InitWithCallback(
+        this, aTimeout, nsITimer::TYPE_ONE_SHOT);
+    NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                         "nsITimer::InitWithCallback() failed, but ignored");
+  }
+
+  return NS_OK;
+}
+
+// static
+char16_t TextEditor::PasswordMask() {
+  char16_t ret = LookAndFeel::GetPasswordCharacter();
+  if (!ret) {
+    ret = '*';
+  }
+  return ret;
+}
+
+MOZ_CAN_RUN_SCRIPT_BOUNDARY NS_IMETHODIMP TextEditor::Notify(nsITimer* aTimer) {
+  // Check whether our text editor's password flag was changed before this
+  // "hide password character" timer actually fires.
+  if (!IsPasswordEditor() || NS_WARN_IF(!mPasswordMaskData)) {
+    return NS_OK;
+  }
+
+  if (IsAllMasked()) {
+    return NS_OK;
+  }
+
+  AutoEditActionDataSetter editActionData(*this, EditAction::eHidePassword);
+  if (NS_WARN_IF(!editActionData.CanHandle())) {
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+
+  // Mask all characters.
+  nsresult rv = MaskAllCharactersAndNotify();
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "TextEditor::MaskAllCharactersAndNotify() failed");
+
+  if (StaticPrefs::editor_password_testing_mask_delay()) {
+    if (RefPtr<Element> target = GetInputEventTargetElement()) {
+      RefPtr<Document> document = target->OwnerDoc();
+      DebugOnly<nsresult> rvIgnored = nsContentUtils::DispatchTrustedEvent(
+          document, target, u"MozLastInputMasked"_ns, CanBubble::eYes,
+          Cancelable::eNo);
+      NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                           "nsContentUtils::DispatchTrustedEvent("
+                           "MozLastInputMasked) failed, but ignored");
+    }
+  }
+
+  return EditorBase::ToGenericNSResult(rv);
+}
+
+NS_IMETHODIMP TextEditor::GetName(nsACString& aName) {
+  aName.AssignLiteral("TextEditor");
+  return NS_OK;
+}
+
+void TextEditor::WillDeleteText(uint32_t aCurrentLength,
+                                uint32_t aRemoveStartOffset,
+                                uint32_t aRemoveLength) {
+  MOZ_ASSERT(IsEditActionDataAvailable());
+
+  if (!IsPasswordEditor() || NS_WARN_IF(!mPasswordMaskData) || IsAllMasked()) {
+    return;
+  }
+
+  // Adjust unmasked range before deletion since DOM mutation may cause
+  // layout referring the range in old text.
+
+  // If we need to mask automatically, mask all now.
+  if (IsMaskingPassword()) {
+    DebugOnly<nsresult> rvIgnored = MaskAllCharacters();
+    NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                         "TextEditor::MaskAllCharacters() failed, but ignored");
+    return;
+  }
+
+  if (aRemoveStartOffset < UnmaskedStart()) {
+    // If removing range is before the unmasked range, move it.
+    if (aRemoveStartOffset + aRemoveLength <= UnmaskedStart()) {
+      DebugOnly<nsresult> rvIgnored =
+          SetUnmaskRange(UnmaskedStart() - aRemoveLength, UnmaskedLength());
+      NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                           "TextEditor::SetUnmaskRange() failed, but ignored");
+      return;
+    }
+
+    // If removing range starts before unmasked range, and ends in unmasked
+    // range, move and shrink the range.
+    if (aRemoveStartOffset + aRemoveLength < UnmaskedEnd()) {
+      uint32_t unmaskedLengthInRemovingRange =
+          aRemoveStartOffset + aRemoveLength - UnmaskedStart();
+      DebugOnly<nsresult> rvIgnored = SetUnmaskRange(
+          aRemoveStartOffset, UnmaskedLength() - unmaskedLengthInRemovingRange);
+      NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                           "TextEditor::SetUnmaskRange() failed, but ignored");
+      return;
+    }
+
+    // If removing range includes all unmasked range, collapse it to the
+    // remove offset.
+    DebugOnly<nsresult> rvIgnored = SetUnmaskRange(aRemoveStartOffset, 0);
+    NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                         "TextEditor::SetUnmaskRange() failed, but ignored");
+    return;
+  }
+
+  if (aRemoveStartOffset < UnmaskedEnd()) {
+    // If removing range is in unmasked range, shrink the range.
+    if (aRemoveStartOffset + aRemoveLength <= UnmaskedEnd()) {
+      DebugOnly<nsresult> rvIgnored =
+          SetUnmaskRange(UnmaskedStart(), UnmaskedLength() - aRemoveLength);
+      NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                           "TextEditor::SetUnmaskRange() failed, but ignored");
+      return;
+    }
+
+    // If removing range starts from unmasked range, and ends after it,
+    // shrink it.
+    DebugOnly<nsresult> rvIgnored =
+        SetUnmaskRange(UnmaskedStart(), aRemoveStartOffset - UnmaskedStart());
+    NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                         "TextEditor::SetUnmaskRange() failed, but ignored");
+    return;
+  }
+
+  // If removing range is after the unmasked range, keep it.
+}
+
+nsresult TextEditor::DidInsertText(uint32_t aNewLength,
+                                   uint32_t aInsertedOffset,
+                                   uint32_t aInsertedLength) {
+  MOZ_ASSERT(IsEditActionDataAvailable());
+
+  if (!IsPasswordEditor() || NS_WARN_IF(!mPasswordMaskData) || IsAllMasked()) {
+    return NS_OK;
+  }
+
+  if (IsMaskingPassword()) {
+    // If we need to mask password, mask all right now.
+    nsresult rv = MaskAllCharactersAndNotify();
+    NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                         "TextEditor::MaskAllCharacters() failed");
+    return rv;
+  }
+
+  if (aInsertedOffset < UnmaskedStart()) {
+    // If insertion point is before unmasked range, expand the unmasked range
+    // to include the new text.
+    nsresult rv = SetUnmaskRangeAndNotify(
+        aInsertedOffset, UnmaskedEnd() + aInsertedLength - aInsertedOffset);
+    NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                         "TextEditor::SetUnmaskRangeAndNotify() failed");
+    return rv;
+  }
+
+  if (aInsertedOffset <= UnmaskedEnd()) {
+    // If insertion point is in unmasked range, unmask new text.
+    nsresult rv = SetUnmaskRangeAndNotify(UnmaskedStart(),
+                                          UnmaskedLength() + aInsertedLength);
+    NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                         "TextEditor::SetUnmaskRangeAndNotify() failed");
+    return rv;
+  }
+
+  // If insertion point is after unmasked range, extend the unmask range to
+  // include the new text.
+  nsresult rv = SetUnmaskRangeAndNotify(
+      UnmaskedStart(), aInsertedOffset + aInsertedLength - UnmaskedStart());
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "TextEditor::SetUnmaskRangeAndNotify() failed");
+  return rv;
+}
+
+}  // namespace mozilla