Wrong caret position in Report Bug dialog when focused due...

chrome/views/text_field.cc

 // Copyright (c) 2006-2008 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 "chrome/views/text_field.h"
 
 #include <atlbase.h>
 #include <atlapp.h>
 #include <atlcrack.h>
 #include <atlctrls.h>
@@ skipping 801 matching lines @@
                                               bool is_triple_click) const {
   // Clip the X coordinate to the left edge of the text.  Careful:
   // PosFromChar(0) may return a negative X coordinate if the beginning of the
   // text has scrolled off the edit, so don't go past the clip rect's edge.
   RECT r;
   GetRect(&r);
   const int left_bound = std::max(r.left, PosFromChar(0).x);
   if (x < left_bound)
     return left_bound;
 
-  // See if we need to clip to the right edge of the text.
-  const int length = GetTextLength();
   // Asking for the coordinate of any character past the end of the text gets
   // the pixel just to the right of the last character.
-  const int right_bound = std::min(r.right, PosFromChar(length).x);
-  if ((length == 0) || (x < right_bound))
+  const int right_bound = std::min(r.right, PosFromChar(x).x);

[Peter Kasting, 2008/12/01 00:28:28]

The old code is definitely wrong for multiline textfields, but the new code is
wrong in general.  PosFromChar(x) isn't meaningful, because x is a pixel
coordinate, not a character index.  And it's not always legal to return x if x
== 0.

It seems like you're going to have to worry about y-coordinates somehow.  I'm
not sure.  Perhaps in the multiline case, we can bypass all the ClipXCoord...()
processing entirely and just let the edit behave the default way?  You'd have to
check whether the "phantom newline" comes back, though.

+  if ((x == 0) || (x < right_bound))
     return x;
 
   // For trailing characters that are 2 pixels wide of less (like "l" in some
   // fonts), we have a problem:
   //   * Clicks on any pixel within the character will place the cursor before
   //     the character.
   //   * Clicks on the pixel just after the character will not allow triple-
   //     click to work properly (true for any last character width).
   // So, we move to the last pixel of the character when this is a
   // triple-click, and moving to one past the last pixel in all other
@@ skipping 241 matching lines @@
 
   COLORREF bg_color;
   if (!use_default_background_color_)
     bg_color = gfx::SkColorToCOLORREF(background_color_);
   else
     bg_color = GetSysColor(read_only_ ? COLOR_3DFACE : COLOR_WINDOW);
   edit_->SetBackgroundColor(bg_color);
 }
 
 }  // namespace views