Use ContainerNode::hasChildren() instead of firstChild() in conditionals

Source/core/editing/ReplaceSelectionCommand.cpp

 /*
  * Copyright (C) 2005, 2006, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2009, 2010, 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 130 matching lines @@
 }
 
 ReplacementFragment::ReplacementFragment(Document* document, DocumentFragment* fragment, const VisibleSelection& selection)
     : m_document(document),
       m_fragment(fragment),
       m_hasInterchangeNewlineAtStart(false),
       m_hasInterchangeNewlineAtEnd(false)
 {
     if (!m_document)
         return;
-    if (!m_fragment)
-        return;
-    if (!m_fragment->firstChild())
+    if (!m_fragment || !m_fragment->hasChildren())
         return;
 
     RefPtrWillBeRawPtr<Element> editableRoot = selection.rootEditableElement();
     ASSERT(editableRoot);
     if (!editableRoot)
         return;
 
     Node* shadowAncestorNode;
     if (editableRoot->isInShadowTree())
         shadowAncestorNode = editableRoot->shadowHost();
@@ skipping 21 matching lines @@
     removeUnrenderedNodes(holder.get());
     restoreAndRemoveTestRenderingNodesToFragment(holder.get());
 
     // Give the root a chance to change the text.
     RefPtrWillBeRawPtr<BeforeTextInsertedEvent> evt = BeforeTextInsertedEvent::create(text);
     editableRoot->dispatchEvent(evt, ASSERT_NO_EXCEPTION);
     if (text != evt->text() || !editableRoot->rendererIsRichlyEditable()) {
         restoreAndRemoveTestRenderingNodesToFragment(holder.get());
 
         m_fragment = createFragmentFromText(selection.toNormalizedRange().get(), evt->text());
-        if (!m_fragment->firstChild())
+        if (!m_fragment->hasChildren())
             return;
 
         holder = insertFragmentForTestRendering(editableRoot.get());
         removeInterchangeNodes(holder.get());
         removeUnrenderedNodes(holder.get());
         restoreAndRemoveTestRenderingNodesToFragment(holder.get());
     }
 }
 
 bool ReplacementFragment::isEmpty() const
 {
-    return (!m_fragment || !m_fragment->firstChild()) && !m_hasInterchangeNewlineAtStart && !m_hasInterchangeNewlineAtEnd;
+    return (!m_fragment || !m_fragment->hasChildren()) && !m_hasInterchangeNewlineAtStart && !m_hasInterchangeNewlineAtEnd;
 }
 
 Node *ReplacementFragment::firstChild() const
 {
     return m_fragment ? m_fragment->firstChild() : 0;
 }
 
 Node *ReplacementFragment::lastChild() const
 {
     return m_fragment ? m_fragment->lastChild() : 0;
@@ skipping 323 matching lines @@
             removeNodePreservingChildren(element);
             continue;
         }
 
         if (element->parentNode() && element->parentNode()->rendererIsRichlyEditable())
             removeNodeAttribute(element, contenteditableAttr);
 
         // WebKit used to not add display: inline and float: none on copy.
         // Keep this code around for backward compatibility
         if (isLegacyAppleStyleSpan(element)) {
-            if (!element->firstChild()) {
+            if (!element->hasChildren()) {
                 insertedNodes.willRemoveNodePreservingChildren(*element);
                 removeNodePreservingChildren(element);
                 continue;
             }
             // There are other styles that style rules can give to style spans,
             // but these are the two important ones because they'll prevent
             // inserted content from appearing in the right paragraph.
             // FIXME: Hyatt is concerned that selectively using display:inline will give inconsistent
             // results. We already know one issue because td elements ignore their display property
             // in quirks mode (which Mail.app is always in). We should look for an alternative.
@@ skipping 100 matching lines @@
         removeNode(node);
         if (ancestor->nextSibling())
             insertNodeBefore(node, ancestor->nextSibling());
         else
             appendNode(node, ancestor->parentNode());
     } else {
         RefPtrWillBeRawPtr<Node> nodeToSplitTo = splitTreeToNode(node.get(), ancestor.get(), true);
         removeNode(node);
         insertNodeBefore(node, nodeToSplitTo);
     }
-    if (!ancestor->firstChild())
+    if (!ancestor->hasChildren())
         removeNode(ancestor.release());
 }
 
 static inline bool nodeHasVisibleRenderText(Text& text)
 {
     return text.renderer() && text.renderer()->renderedTextLength() > 0;
 }
 
 void ReplaceSelectionCommand::removeUnrenderedTextNodesAtEnds(InsertedNodes& insertedNodes)
 {
@@ skipping 112 matching lines @@
     // This operation requires that only editing styles to be removed from sourceDocumentStyle.
     style->prepareToApplyAt(firstPositionInNode(context));
 
     // Remove block properties in the span's style. This prevents properties that probably have no effect
     // currently from affecting blocks later if the style is cloned for a new block element during a future
     // editing operation.
     // FIXME: They *can* have an effect currently if blocks beneath the style span aren't individually marked
     // with block styles by the editing engine used to style them.  WebKit doesn't do this, but others might.
     style->removeBlockProperties();
 
-    if (style->isEmpty() || !wrappingStyleSpan->firstChild()) {
+    if (style->isEmpty() || !wrappingStyleSpan->hasChildren()) {
         insertedNodes.willRemoveNodePreservingChildren(*wrappingStyleSpan);
         removeNodePreservingChildren(wrappingStyleSpan);
     } else {
         setNodeAttribute(wrappingStyleSpan, styleAttr, AtomicString(style->style()->asText()));
     }
 }
 
 void ReplaceSelectionCommand::mergeEndIfNeeded()
 {
     if (!m_shouldMergeEnd)
@@ skipping 714 matching lines @@
 void ReplaceSelectionCommand::trace(Visitor* visitor)
 {
     visitor->trace(m_startOfInsertedContent);
     visitor->trace(m_endOfInsertedContent);
     visitor->trace(m_insertionStyle);
     visitor->trace(m_documentFragment);
     CompositeEditCommand::trace(visitor);
 }
 
 } // namespace blink