Extract SelectionPaintRange calculation from LayoutSelection::Commit()

third_party/WebKit/Source/core/editing/LayoutSelection.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights
  * reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 61 matching lines @@
 int SelectionPaintRange::EndOffset() const {
   DCHECK(!IsNull());
   return end_offset_;
 }
 
 LayoutSelection::LayoutSelection(FrameSelection& frame_selection)
     : frame_selection_(&frame_selection),
       has_pending_selection_(false),
       paint_range_(SelectionPaintRange()) {}
 
-SelectionInFlatTree LayoutSelection::CalcVisibleSelection(
-    const VisibleSelectionInFlatTree& original_selection) const {
+static SelectionInFlatTree CalcSelection(
+    const VisibleSelectionInFlatTree& original_selection,
+    bool should_show_blok_cursor) {
   const PositionInFlatTree& start = original_selection.Start();
   const PositionInFlatTree& end = original_selection.end();
   SelectionType selection_type = original_selection.GetSelectionType();
   const TextAffinity affinity = original_selection.Affinity();
 
   bool paint_block_cursor =
-      frame_selection_->ShouldShowBlockCursor() &&
+      should_show_blok_cursor &&
       selection_type == SelectionType::kCaretSelection &&
       !IsLogicalEndOfLine(CreateVisiblePosition(end, affinity));
   if (EnclosingTextControl(start.ComputeContainerNode())) {
     // TODO(yosin) We should use |PositionMoveType::CodePoint| to avoid
     // ending paint at middle of character.
     PositionInFlatTree end_position =
         paint_block_cursor ? NextPositionOf(original_selection.Extent(),
                                             PositionMoveType::kCodeUnit)
                            : end;
     return SelectionInFlatTree::Builder()
@@ skipping 207 matching lines @@
     layout_object->SetSelectionStateIfNeeded(SelectionState::kNone);
     if (layout_object->GetSelectionState() == old_state)
       continue;
     layout_object->SetShouldInvalidateSelection();
   }
 
   // Reset selection.
   paint_range_ = SelectionPaintRange();
 }
 
-void LayoutSelection::Commit() {
-  if (!HasPendingSelection())
-    return;
-  has_pending_selection_ = false;
-
+static SelectionPaintRange CalcSelectionPaintRange(
+    const FrameSelection& frame_selection) {
   const VisibleSelectionInFlatTree& original_selection =
-      frame_selection_->ComputeVisibleSelectionInFlatTree();
-
+      frame_selection.ComputeVisibleSelectionInFlatTree();
   // Construct a new VisibleSolution, since visibleSelection() is not
   // necessarily valid, and the following steps assume a valid selection. See
   // <https://bugs.webkit.org/show_bug.cgi?id=69563> and
   // <rdar://problem/10232866>.
+  const SelectionInFlatTree& new_selection = CalcSelection(
+      original_selection, frame_selection.ShouldShowBlockCursor());
   const VisibleSelectionInFlatTree& selection =
-      CreateVisibleSelection(CalcVisibleSelection(original_selection));
+      CreateVisibleSelection(new_selection);
 
-  if (!selection.IsRange() || frame_selection_->IsHidden()) {
-    ClearSelection();
-    return;
-  }
+  if (!selection.IsRange() || frame_selection.IsHidden())
+    return SelectionPaintRange();
+
   DCHECK(!selection.IsNone());
   // Use the rightmost candidate for the start of the selection, and the
   // leftmost candidate for the end of the selection. Example: foo <a>bar</a>.
   // Imagine that a line wrap occurs after 'foo', and that 'bar' is selected.
   // If we pass [foo, 3] as the start of the selection, the selection painting
   // code will think that content on the line containing 'foo' is selected
   // and will fill the gap before 'bar'.
   PositionInFlatTree start_pos = selection.Start();
   const PositionInFlatTree most_forward_start =
       MostForwardCaretPosition(start_pos);
   if (IsVisuallyEquivalentCandidate(most_forward_start))
     start_pos = most_forward_start;
   PositionInFlatTree end_pos = selection.end();
   const PositionInFlatTree most_backward = MostBackwardCaretPosition(end_pos);
   if (IsVisuallyEquivalentCandidate(most_backward))
     end_pos = most_backward;
 
   DCHECK(start_pos.IsNotNull());
   DCHECK(end_pos.IsNotNull());
   DCHECK_LE(start_pos, end_pos);
   LayoutObject* start_layout_object = start_pos.AnchorNode()->GetLayoutObject();
   LayoutObject* end_layout_object = end_pos.AnchorNode()->GetLayoutObject();
   DCHECK(start_layout_object);
   DCHECK(end_layout_object);
   DCHECK(start_layout_object->View() == end_layout_object->View());
 
-  const SelectionPaintRange new_range(
-      start_layout_object, start_pos.ComputeEditingOffset(), end_layout_object,
-      end_pos.ComputeEditingOffset());
+  return SelectionPaintRange(start_layout_object,
+                             start_pos.ComputeEditingOffset(),
+                             end_layout_object, end_pos.ComputeEditingOffset());
+}
+
+void LayoutSelection::Commit() {
+  if (!HasPendingSelection())
+    return;
+  has_pending_selection_ = false;
+
+  const SelectionPaintRange& new_range =
+      CalcSelectionPaintRange(*frame_selection_);
+  if (new_range.IsNull()) {
+    ClearSelection();
+    return;
+  }
   // Just return if the selection hasn't changed.
   if (paint_range_ == new_range)
     return;
 
   DCHECK(frame_selection_->GetDocument().GetLayoutView()->GetFrameView());
   DCHECK(!frame_selection_->GetDocument().NeedsLayoutTreeUpdate());
   UpdateLayoutObjectState(new_range, paint_range_);
   paint_range_ = new_range;
 }
 
@@ skipping 66 matching lines @@
 
     o->SetShouldInvalidateSelection();
   }
 }
 
 DEFINE_TRACE(LayoutSelection) {
   visitor->Trace(frame_selection_);
 }
 
 }  // namespace blink