Implement eliding/truncating at end in RenderText

base/i18n/rtl.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 "base/i18n/rtl.h"
 
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/strings/string_util.h"
 #include "base/strings/sys_string_conversions.h"
@@ skipping 145 matching lines @@
     size_t next_position = position;
     U16_NEXT(string, next_position, length, character);
     TextDirection direction = GetCharacterDirection(character);
     if (direction != UNKNOWN_DIRECTION)
       return direction;
     position = next_position;
   }
   return LEFT_TO_RIGHT;
 }
 
+TextDirection GetLastStrongCharacterDirection(const string16& text) {
+  const UChar* string = text.c_str();
+  size_t position = text.length();
+  while (position > 0) {
+    UChar32 character;
+    size_t prev_position = position;
+    U16_PREV(string, 0, prev_position, character);
+    TextDirection direction = GetCharacterDirection(character);
+    if (direction != UNKNOWN_DIRECTION)
+      return direction;
+    position = prev_position;
+  }
+  return LEFT_TO_RIGHT;
+}
+
 TextDirection GetStringDirection(const string16& text) {
   const UChar* string = text.c_str();
   size_t length = text.length();
   size_t position = 0;
 
   TextDirection result(UNKNOWN_DIRECTION);
   while (position < length) {
     UChar32 character;
     size_t next_position = position;
     U16_NEXT(string, next_position, length, character);
@@ skipping 198 matching lines @@
       begin == kRightToLeftOverride)
     ++begin_index;
   size_t end_index = text.length() - 1;
   if (text[end_index] == kPopDirectionalFormatting)
     --end_index;
   return text.substr(begin_index, end_index - begin_index + 1);
 }
 
 }  // namespace i18n
 }  // namespace base