Avoid creating duplicate Range objects when handling misspellings.

third_party/WebKit/Source/core/editing/spellcheck/SpellCheckRequester.cpp

 /*
  * Copyright (C) 2010 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 50 matching lines @@
 DEFINE_TRACE(SpellCheckRequest)
 {
     visitor->trace(m_requester);
     visitor->trace(m_checkingRange);
     visitor->trace(m_paragraphRange);
     visitor->trace(m_rootEditableElement);
     TextCheckingRequest::trace(visitor);
 }
 
 // static
-PassRefPtrWillBeRawPtr<SpellCheckRequest> SpellCheckRequest::create(TextCheckingTypeMask textCheckingOptions, TextCheckingProcessType processType, PassRefPtrWillBeRawPtr<Range> checkingRange, PassRefPtrWillBeRawPtr<Range> paragraphRange, int requestNumber)
+PassRefPtrWillBeRawPtr<SpellCheckRequest> SpellCheckRequest::create(TextCheckingTypeMask textCheckingOptions, TextCheckingProcessType processType, const EphemeralRange& checkingRange, const EphemeralRange& paragraphRange, int requestNumber)
 {
-    ASSERT(checkingRange);
-    ASSERT(paragraphRange);
-
-    String text = checkingRange->text();
-    if (!text.length())
+    String text = plainText(checkingRange, TextIteratorEmitsObjectReplacementCharacter);
+    if (text.isEmpty())
         return nullptr;
 
-    const DocumentMarkerVector& markers = checkingRange->ownerDocument().markers().markersInRange(EphemeralRange(checkingRange.get()), DocumentMarker::SpellCheckClientMarkers());
+    RefPtrWillBeRawPtr<Range> checkingRangeObject = createRange(checkingRange);
+    RefPtrWillBeRawPtr<Range> paragraphRangeObject = nullptr;
+    // Share identical Range objects.
+    if (checkingRange == paragraphRange)
+        paragraphRangeObject = checkingRangeObject;
+    else
+        paragraphRangeObject = createRange(paragraphRange);
+
+    const DocumentMarkerVector& markers = checkingRangeObject->ownerDocument().markers().markersInRange(checkingRange, DocumentMarker::SpellCheckClientMarkers());
     Vector<uint32_t> hashes(markers.size());
     Vector<unsigned> offsets(markers.size());
-    for (size_t i = 0; i < markers.size(); i++) {
+    for (size_t i = 0; i < markers.size(); ++i) {
         hashes[i] = markers[i]->hash();
         offsets[i] = markers[i]->startOffset();
     }
 
-    return adoptRefWillBeNoop(new SpellCheckRequest(checkingRange, paragraphRange, text, textCheckingOptions, processType, hashes, offsets, requestNumber));
+    return adoptRefWillBeNoop(new SpellCheckRequest(checkingRangeObject, paragraphRangeObject, text, textCheckingOptions, processType, hashes, offsets, requestNumber));
 }
 
 const TextCheckingRequestData& SpellCheckRequest::data() const
 {
     return m_requestData;
 }
 
 void SpellCheckRequest::didSucceed(const Vector<TextCheckingResult>& results)
 {
     if (!m_requester)
@@ skipping 108 matching lines @@
 void SpellCheckRequester::invokeRequest(PassRefPtrWillBeRawPtr<SpellCheckRequest> request)
 {
     ASSERT(!m_processingRequest);
     m_processingRequest = request;
     client().requestCheckingOfString(m_processingRequest);
 }
 
 void SpellCheckRequester::clearProcessingRequest()
 {
     // This assumes that m_processingRequest's Ranges aren't shared.
-    if (m_processingRequest->checkingRange())
-        m_processingRequest->checkingRange()->dispose();
-    if (m_processingRequest->paragraphRange())
-        m_processingRequest->paragraphRange()->dispose();
+    RefPtrWillBeRawPtr<Range> checkingRange = m_processingRequest->checkingRange();

[yosin_UTC9, 2015/09/26 15:46:06]

nit: Can we have |SpellCheckRequest::dispose()| or Make
|SpellCheckRequest::clear()| to dispose |checkingRange| and |paragraphRange|?
We may not want to check equality of |checkingRange| and |paragraphRange|
here. It is an implementation details.

[sof, 2015/09/26 16:18:29]

Addressed.

+    RefPtrWillBeRawPtr<Range> paragraphRange = m_processingRequest->paragraphRange();
+    if (checkingRange)
+        checkingRange->dispose();
+    if (paragraphRange && paragraphRange != checkingRange)
+        paragraphRange->dispose();
 
     m_processingRequest.clear();
 }
 
 void SpellCheckRequester::enqueueRequest(PassRefPtrWillBeRawPtr<SpellCheckRequest> request)
 {
     ASSERT(request);
     bool continuation = false;
     if (!m_requestQueue.isEmpty()) {
         RefPtrWillBeRawPtr<SpellCheckRequest> lastRequest = m_requestQueue.last();
@@ skipping 58 matching lines @@
 }
 
 DEFINE_TRACE(SpellCheckRequester)
 {
     visitor->trace(m_frame);
     visitor->trace(m_processingRequest);
     visitor->trace(m_requestQueue);
 }
 
 } // namespace blink