Refactor DocumentMarkerController

third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp

Index: third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp
diff --git a/third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp b/third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp
index b18b3fd88304206850783d3ee5de7a20483edd5f..9cd36b618bcc1511e719c9a7a7ea06bb3cc28c1e 100644
--- a/third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp
+++ b/third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp
@@ -30,6 +30,7 @@
 
 #include "core/editing/markers/DocumentMarker.h"
 
+#include "core/editing/markers/RenderedTextMatchMarker.h"

[Xiaocheng, 2017/03/21 03:59:44]

This seems redundant.

 #include "wtf/StdLibExtras.h"
 
 namespace blink {
@@ -166,11 +167,59 @@ DocumentMarker::DocumentMarker(const DocumentMarker& marker)
       m_endOffset(marker.endOffset()),
       m_details(marker.details()) {}
 
+DocumentMarker::ShiftMarkerResult DocumentMarker::getShiftedMarkerPosition(
+    unsigned offset,
+    unsigned oldLength,
+    unsigned newLength) {
+  ShiftMarkerResult result;
+  result.newStartOffset = startOffset();
+  result.newEndOffset = endOffset();
+  result.shouldRemoveMarker = false;
+
+  // algorithm inspired by https://dom.spec.whatwg.org/#concept-cd-replace
+  // but with some changes
+  if (startOffset() > offset) {
+    // Deviation from the concept-cd-replace algorithm: < instead of <= in
+    // the next line
+    if (startOffset() < offset + oldLength) {
+      // Marker start was in the replaced text. Move to end of new text
+      // (Deviation from the concept-cd-replace algorithm: that algorithm
+      // would move to the beginning of the new text here)
+      result.newStartOffset = offset + newLength;
+    } else {
+      // Marker start was after the replaced text. Shift by length
+      // difference
+      result.newStartOffset = startOffset() + newLength - oldLength;
+    }
+  }
+
+  if (endOffset() > offset) {
+    // Deviation from the concept-cd-replace algorithm: < instead of <= in
+    // the next line
+    if (endOffset() < offset + oldLength) {
+      // Marker end was in the replaced text. Move to beginning of new text
+      result.newEndOffset = offset;
+    } else {
+      // Marker end was after the replaced text. Shift by length difference
+      result.newEndOffset = endOffset() + newLength - oldLength;
+    }
+  }
+
+  if (result.newStartOffset >= result.newEndOffset)
+    result.shouldRemoveMarker = true;
+
+  return result;
+}
+
 void DocumentMarker::shiftOffsets(int delta) {
   m_startOffset += delta;
   m_endOffset += delta;
 }
 
+bool DocumentMarker::isRenderedTextMatch() const {
+  return false;
+}
+
 void DocumentMarker::setActiveMatch(bool active) {
   m_details = DocumentMarkerTextMatch::create(active);
 }