1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "chrome/browser/spellchecker/word_trimmer.h" 6 7 #include <algorithm> 8 #include <vector> 9 10 #include "base/i18n/break_iterator.h" 11 12 base::string16 TrimWords(size_t* start, 13 size_t end, 14 const base::string16& text, 15 size_t keep) { 16 if (*start > text.length() || *start > end) 17 return text; 18 base::i18n::BreakIterator iter(text, base::i18n::BreakIterator::BREAK_WORD); 19 if (!iter.Init()) 20 return text; 21 // A circular buffer of the last |keep + 1| words seen before position |start| 22 // in |text|. 23 std::vector<size_t> word_offset(keep + 1, 0); 24 size_t first = std::string::npos; 25 size_t last = std::string::npos; 26 while (iter.Advance()) { 27 if (iter.IsWord()) { 28 word_offset[keep] = iter.prev(); 29 if ((*start >= iter.prev() && *start < iter.pos()) || 30 (end > iter.prev() && end <= iter.pos())) { 31 if (first == std::string::npos) 32 first = word_offset[0]; 33 last = iter.pos(); 34 } 35 if (first == std::string::npos) { 36 std::rotate(word_offset.begin(), 37 word_offset.begin() + 1, 38 word_offset.end()); 39 } 40 if (iter.prev() > end && keep) { 41 last = iter.pos(); 42 keep--; 43 } 44 } 45 } 46 if (first == std::string::npos) 47 return text; 48 *start -= first; 49 return text.substr(first, last - first); 50 } 51
