Bug 1713334 - Part 3: Assume TextEditor always have a text node r=masayuki

Differential Revision: https://phabricator.services.mozilla.com/D117023

dom/events/test/test_bug328885.html

@@ -68,6 +68,9 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=328885
         evt.originalTarget.setAttribute("foo", "bar");
         ok(mutationCount == 0, "(10) Mutation listener shouldn't have been called! ["+ mutationCount + "]");
 
+        // We played with the internal div, now restore its initial state
+        evt.originalTarget.replaceChildren(new Text());
+
         // Same tests with non-native-anononymous element.
         // mutationCount should be increased by 2 each time, since there is
         // first a mutation specific event and then DOMSubtreeModified.

editor/libeditor/EditorBase.cpp

@@ -5393,7 +5393,6 @@ nsresult EditorBase::ReplaceTextAsAction(
 }
 
 nsresult EditorBase::ReplaceSelectionAsSubAction(const nsAString& aString) {
-  // TODO: Move this method to `EditorBase`.
   if (aString.IsEmpty()) {
     nsresult rv = DeleteSelectionAsSubAction(
         nsIEditor::eNone,

editor/libeditor/TextEditSubActionHandler.cpp

@@ -600,36 +600,22 @@ EditActionResult TextEditor::SetTextWithoutTransaction(
   }
 
   RefPtr<Element> anonymousDivElement = GetRoot();
-  nsIContent* firstChild = anonymousDivElement->GetFirstChild();
+  RefPtr<Text> textNode =
+      Text::FromNodeOrNull(anonymousDivElement->GetFirstChild());
+  MOZ_ASSERT(textNode);
 
   // We can use this fast path only when:
   //  - we need to insert a text node.
   //  - we need to replace content of existing text node.
   // Additionally, for avoiding odd result, we should check whether we're in
   // usual condition.
-  if (IsSingleLineEditor()) {
-    // If we're a single line text editor, i.e., <input>, there is only padding
-    // <br> element.  Otherwise, there should be only one text node.  But note
-    // that even if there is a padding <br> element for empty editor, it's
-    // already been removed by `EnsureNoPaddingBRElementForEmptyEditor()`.  So,
-    // at here, there should be only one text node or no children.
-    if (firstChild && (!firstChild->IsText() || firstChild->GetNextSibling())) {
-      return EditActionIgnored();
-    }
-  } else {
+  if (!IsSingleLineEditor()) {
     // If we're a multiline text editor, i.e., <textarea>, there is a padding
     // <br> element for empty last line followed by scrollbar/resizer elements.
     // Otherwise, a text node is followed by them.
-    if (!firstChild) {
-      return EditActionIgnored();
-    }
-    if (firstChild->IsText()) {
-      if (!firstChild->GetNextSibling() ||
-          !EditorUtils::IsPaddingBRElementForEmptyLastLine(
-              *firstChild->GetNextSibling())) {
-        return EditActionIgnored();
-      }
-    } else if (!EditorUtils::IsPaddingBRElementForEmptyLastLine(*firstChild)) {
+    if (!textNode->GetNextSibling() ||
+        !EditorUtils::IsPaddingBRElementForEmptyLastLine(
+            *textNode->GetNextSibling())) {
       return EditActionIgnored();
     }
   }
@@ -641,36 +627,6 @@ EditActionResult TextEditor::SetTextWithoutTransaction(
     HandleNewLinesInStringForSingleLineEditor(sanitizedValue);
   }
 
-  if (!firstChild || !firstChild->IsText()) {
-    if (sanitizedValue.IsEmpty()) {
-      return EditActionHandled();
-    }
-    RefPtr<Document> document = GetDocument();
-    if (NS_WARN_IF(!document)) {
-      return EditActionIgnored();
-    }
-    RefPtr<nsTextNode> newTextNode = CreateTextNode(sanitizedValue);
-    if (!newTextNode) {
-      NS_WARNING("EditorBase::CreateTextNode() failed");
-      return EditActionIgnored();
-    }
-    nsresult rv = InsertNodeWithTransaction(
-        *newTextNode, EditorDOMPoint(anonymousDivElement, 0));
-    if (NS_WARN_IF(Destroyed())) {
-      return EditActionResult(NS_ERROR_EDITOR_DESTROYED);
-    }
-    if (NS_FAILED(rv)) {
-      NS_WARNING("EditorBase::InsertNodeWithTransaction() failed");
-      return EditActionResult(rv);
-    }
-    return EditActionHandled();
-  }
-
-  RefPtr<Text> textNode = firstChild->GetAsText();
-  if (MOZ_UNLIKELY(!textNode)) {
-    NS_WARNING("The first child was not a text node");
-    return EditActionIgnored();
-  }
   rv = SetTextNodeWithoutTransaction(sanitizedValue, *textNode);
   if (NS_FAILED(rv)) {
     NS_WARNING("EditorBase::SetTextNodeWithoutTransaction() failed");
@@ -691,9 +647,7 @@ EditActionResult TextEditor::HandleDeleteSelection(
 
   CANCEL_OPERATION_AND_RETURN_EDIT_ACTION_RESULT_IF_READONLY
 
-  // if there is only padding <br> element for empty editor, cancel the
-  // operation.
-  if (mPaddingBRElementForEmptyEditor) {
+  if (IsEmpty()) {
     return EditActionCanceled();
   }
   EditActionResult result =
@@ -785,37 +739,15 @@ EditActionResult TextEditor::ComputeValueFromTextNodeAndBRElement(
     return EditActionHandled();
   }
 
-  nsIContent* textNodeOrPaddingBRElement = anonymousDivElement->GetFirstChild();
-  if (!textNodeOrPaddingBRElement ||
-      textNodeOrPaddingBRElement == mPaddingBRElementForEmptyEditor) {
+  Text* textNode = Text::FromNodeOrNull(anonymousDivElement->GetFirstChild());
+  MOZ_ASSERT(textNode);
+
+  if (!textNode->Length()) {
     aValue.Truncate();
     return EditActionHandled();
   }
 
-  // If it's an <input type="text"> element, the DOM tree should be:
-  // <div (::-moz-text-control-editing-root)>
-  //   #text
-  // </div>
-  //
-  // If it's a <textarea> element, the DOM tree should be:
-  // <div (::-moz-text-control-editing-root)>
-  //   #text (if there is)
-  //   <br type="_moz">
-  //   <scrollbar orient="horizontal">
-  //   ...
-  // </div>
-
-  Text* textNode = textNodeOrPaddingBRElement->GetAsText();
-  if (!textNode) {
-    // If there is no text node in the expected DOM tree, we can say that it's
-    // just empty.
-    aValue.Truncate();
-    return EditActionHandled();
-  }
-
-  nsIContent* firstChildExceptText =
-      textNode ? textNodeOrPaddingBRElement->GetNextSibling()
-               : textNodeOrPaddingBRElement;
+  nsIContent* firstChildExceptText = textNode->GetNextSibling();
   // If the DOM tree is unexpected, fall back to the expensive path.
   bool isInput = IsSingleLineEditor();
   bool isTextarea = !isInput;

editor/libeditor/TextEditor.cpp

@@ -368,10 +368,11 @@ bool TextEditor::IsEmpty() const {
     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() ||
-         !anonymousDivElement->GetFirstChild()->IsText() ||
-         !anonymousDivElement->GetFirstChild()->Length();
+  return !anonymousDivElement->GetFirstChild()->Length();
 }
 
 NS_IMETHODIMP TextEditor::GetTextLength(int32_t* aCount) {
@@ -596,13 +597,7 @@ nsresult TextEditor::SelectEntireDocument() {
 
   RefPtr<Text> text =
       Text::FromNodeOrNull(anonymousDivElement->GetFirstChild());
-  if (!text) {
-    ErrorResult error;
-    SelectionRef().CollapseInLimiter(*anonymousDivElement, 0, error);
-    NS_WARNING_ASSERTION(!error.Failed(),
-                         "Selection::SetStartAndEndInLimiter() failed");
-    return error.StealNSResult();
-  }
+  MOZ_ASSERT(text);
 
   MOZ_TRY(SelectionRef().SetStartAndEndInLimiter(
       *text, 0, *text, text->TextDataLength(), eDirNext,

editor/libeditor/tests/mochitest.ini

@@ -224,7 +224,7 @@ skip-if = headless
 [test_bug1399722.html]
 [test_bug1406726.html]
 [test_bug1409520.html]
-[test_bug1425997.html] 
+[test_bug1425997.html]
 [test_bug1497480.html]
 skip-if = toolkit == 'android'
 [test_bug1543312.html]
@@ -311,6 +311,7 @@ skip-if = (verify && debug && os == 'win') # bug 1485293
 skip-if = toolkit == 'android'
 [test_state_change_on_reframe.html]
 [test_textarea_value_not_include_cr.html]
+[test_texteditor_textnode.html]
 [test_typing_at_edge_of_anchor.html]
 [test_undo_after_spellchecker_replaces_word.html]
 skip-if = toolkit == 'android'

editor/libeditor/tests/test_texteditor_textnode.html

@@ -0,0 +1,41 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>Test for Bug 1713334</title>
+<script src="/tests/SimpleTest/SimpleTest.js"></script>
+<script src="/tests/SimpleTest/EventUtils.js"></script>
+<link rel="stylesheet" href="/tests/SimpleTest/test.css">
+<input id="input">
+<textarea id="textarea"></textarea>
+<script>
+"use strict";
+
+function assertChild(div, content) {
+  const name = div.parentElement.localName;
+  is(div.firstChild.nodeType, Node.TEXT_NODE, `<${name}>: The first node of the root element must be a text node`);
+  is(div.firstChild.textContent, content, `<${name}>: The content of the text node is wrong`);
+}
+
+function test(element) {
+  element.focus();
+
+  const { rootElement } = SpecialPowers.wrap(element).editor;
+  assertChild(rootElement, "");
+
+  element.value = "";
+  assertChild(rootElement, "");
+
+  element.value = "foo"
+  assertChild(rootElement, "foo");
+
+  element.value = "";
+  assertChild(rootElement, "");
+}
+
+SimpleTest.waitForExplicitFinish();
+SimpleTest.waitForFocus(() => {
+  test(document.all.input);
+  test(document.all.textarea);
+
+  SimpleTest.finish();
+});
+</script>