Index: ui/base/text/utf16_indexing.cc |
diff --git a/ui/base/text/utf16_indexing.cc b/ui/base/text/utf16_indexing.cc |
deleted file mode 100644 |
index d217f5d75c49fd86923619b9ba4081b07a2fb459..0000000000000000000000000000000000000000 |
--- a/ui/base/text/utf16_indexing.cc |
+++ /dev/null |
@@ -1,55 +0,0 @@ |
-// Copyright (c) 2012 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/base/text/utf16_indexing.h" |
- |
-#include "base/logging.h" |
-#include "base/third_party/icu/icu_utf.h" |
- |
-namespace ui { |
- |
-bool IsValidCodePointIndex(const string16& s, size_t index) { |
- return index == 0 || index == s.length() || |
- !(CBU16_IS_TRAIL(s[index]) && CBU16_IS_LEAD(s[index - 1])); |
-} |
- |
-ptrdiff_t UTF16IndexToOffset(const string16& s, size_t base, size_t pos) { |
- // The indices point between UTF-16 words (range 0 to s.length() inclusive). |
- // In order to consistently handle indices that point to the middle of a |
- // surrogate pair, we count the first word in that surrogate pair and not |
- // the second. The test "s[i] is not the second half of a surrogate pair" is |
- // "IsValidCodePointIndex(s, i)". |
- DCHECK_LE(base, s.length()); |
- DCHECK_LE(pos, s.length()); |
- ptrdiff_t delta = 0; |
- while (base < pos) |
- delta += IsValidCodePointIndex(s, base++) ? 1 : 0; |
- while (pos < base) |
- delta -= IsValidCodePointIndex(s, pos++) ? 1 : 0; |
- return delta; |
-} |
- |
-size_t UTF16OffsetToIndex(const string16& s, size_t base, ptrdiff_t offset) { |
- DCHECK_LE(base, s.length()); |
- // As in UTF16IndexToOffset, we count the first half of a surrogate pair, not |
- // the second. When stepping from pos to pos+1 we check s[pos:pos+1] == s[pos] |
- // (Python syntax), hence pos++. When stepping from pos to pos-1 we check |
- // s[pos-1], hence --pos. |
- size_t pos = base; |
- while (offset > 0 && pos < s.length()) |
- offset -= IsValidCodePointIndex(s, pos++) ? 1 : 0; |
- while (offset < 0 && pos > 0) |
- offset += IsValidCodePointIndex(s, --pos) ? 1 : 0; |
- // If offset != 0 then we ran off the edge of the string, which is a contract |
- // violation but is handled anyway (by clamping) in release for safety. |
- DCHECK_EQ(offset, 0); |
- // Since the second half of a surrogate pair has "length" zero, there is an |
- // ambiguity in the returned position. Resolve it by always returning a valid |
- // index. |
- if (!IsValidCodePointIndex(s, pos)) |
- ++pos; |
- return pos; |
-} |
- |
-} // namespace ui |