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..7465262ac7324e34a6102a1154e37cefc431b5c4 100644 |
--- a/third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp |
+++ b/third_party/WebKit/Source/core/editing/markers/DocumentMarker.cpp |
@@ -166,6 +166,53 @@ DocumentMarker::DocumentMarker(const DocumentMarker& marker) |
m_endOffset(marker.endOffset()), |
m_details(marker.details()) {} |
+DocumentMarker::ShiftMarkerResult DocumentMarker::getShiftedMarkerPosition( |
Xiaocheng
2017/03/29 19:41:43
nit: I think the previous patch should directly im
|
+ unsigned offset, |
+ unsigned oldLength, |
+ unsigned newLength) const { |
+ 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 |
+ |
+ // Deviation from the concept-cd-replace algorithm: second condition in the |
+ // next line (don't include text inserted immediately before a marker in the |
+ // marked range, but do include the new text if it's replacing text in the |
+ // marked range) |
+ if (startOffset() > offset || (startOffset() == offset && oldLength == 0)) { |
+ 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; |