fix know issues in RenderText

ui/gfx/render_text_linux.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/gfx/render_text_linux.h"
 
 #include <pango/pangocairo.h>
 
 #include <algorithm>
 
@@ skipping 105 matching lines @@
   bounds = GetUpdatedCursorBounds();
   if (cursor_visible() && focused())
       canvas->DrawRectInt(kCursorColor,
                           bounds.x(),
                           bounds.y(),
                           bounds.width(),
                           bounds.height());
 }
 
 SelectionModel RenderTextLinux::FindCursorPosition(const Point& point) {
-  // TODO(xji): when points outside of text, return HOME/END position.
   PangoLayout* layout = EnsureLayout();
 
   if (text().empty())
     return SelectionModel(0, 0, SelectionModel::LEADING);
 
   Point p(ToTextPoint(point));
+
+  // When points outside of text, return HOME/END position.

[msw, 2011/09/09 23:03:24]

"When *the point is* outside" or "*For* points outside"

[xji, 2011/09/12 21:31:48]

Done.

+  if (p.x() < 0)
+    return LeftEndSelectionModel();
+  else if (p.x() > GetStringWidth())
+    return RightEndSelectionModel();
+
   int caret_pos, trailing;
   pango_layout_xy_to_index(layout, p.x() * PANGO_SCALE, p.y() * PANGO_SCALE,
                            &caret_pos, &trailing);
 
   size_t selection_end = caret_pos;
   if (trailing > 0) {
     const char* ch = g_utf8_offset_to_pointer(layout_text_ + caret_pos,
                                               trailing);
     DCHECK_GE(ch, layout_text_);
     DCHECK_LE(ch, layout_text_ + layout_text_len_);
@@ skipping 25 matching lines @@
   int h = std::min(display_rect().height(), PANGO_PIXELS(pos.height));
   Rect bounds(x, (display_rect().height() - h) / 2, 0, h);
   bounds.set_origin(ToViewPoint(bounds.origin()));
 
   if (!insert_mode)
     bounds.set_width(std::abs(pos.width));
 
   return bounds;
 }
 
+size_t RenderTextLinux::GetIndexOfNextGrapheme(size_t position) {
+  EnsureLayout();
+  size_t index = Utf16IndexToUtf8Index(position);
+  return Utf16IndexOfAdjacentGrapheme(index, NEXT);
+}
+
 SelectionModel RenderTextLinux::GetLeftSelectionModel(
     const SelectionModel& current,
     BreakType break_type) {
   EnsureLayout();
 
   if (break_type == LINE_BREAK || text().empty())
     return LeftEndSelectionModel();
   if (break_type == CHARACTER_BREAK)
     return LeftSelectionModel(current);
   // TODO(xji): not implemented yet.
@@ skipping 49 matching lines @@
   }
   return SelectionModel(0, 0, SelectionModel::LEADING);
 }
 
 size_t RenderTextLinux::GetIndexOfPreviousGrapheme(size_t position) {
   EnsureLayout();
   size_t index = Utf16IndexToUtf8Index(position);
   return Utf16IndexOfAdjacentGrapheme(index, PREVIOUS);
 }
 
-size_t RenderTextLinux::GetIndexOfNextGrapheme(size_t position) {
+bool RenderTextLinux::IsCursorablePosition(size_t position) {
+  if (position == 0 && text().empty())
+    return true;
+
   EnsureLayout();
-  size_t index = Utf16IndexToUtf8Index(position);
-  return Utf16IndexOfAdjacentGrapheme(index, NEXT);
+  return (position >= 0 && position < (size_t)num_log_attrs_ &&

[msw, 2011/09/09 23:03:24]

Use c++ style static_cast.

[xji, 2011/09/12 21:31:48]

Done.

+          log_attrs_[position].is_cursor_position);
 }
 
 GSList* RenderTextLinux::GetRunContainingPosition(size_t position) const {
   GSList* run = current_line_->runs;
   while (run) {
     PangoItem* item = reinterpret_cast<PangoLayoutRun*>(run->data)->item;
     size_t run_start = Utf8IndexToUtf16Index(item->offset);
     size_t run_end = Utf8IndexToUtf16Index(item->offset + item->length);
 
     if (position >= run_start && position < run_end)
@@ skipping 320 matching lines @@
 size_t RenderTextLinux::Utf8IndexToUtf16Index(size_t index) const {
   int32_t utf16_index = 0;
   UErrorCode ec = U_ZERO_ERROR;
   u_strFromUTF8(NULL, 0, &utf16_index, layout_text_, index, &ec);
   DCHECK(ec == U_BUFFER_OVERFLOW_ERROR ||
          ec == U_STRING_NOT_TERMINATED_WARNING);
   return utf16_index;
 }
 
 }  // namespace gfx