Reintroduce password support to NativeTextfieldViews

ui/base/text/utf16_indexing_unittest.cc

+// 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 "testing/gtest/include/gtest/gtest.h"
+#include "ui/base/text/utf16_indexing.h"
+
+namespace ui {
+
+TEST(UTF16IndexingTest, IndexOffsetConversions) {
+  // Valid surrogate pair surrounded by unpaired surrogates
+  const char16 foo[] = {0xDC00, 0xD800, 0xD800, 0xDFFF, 0xDFFF, 0xDBFF, 0};
+  const string16 s(foo);
+  const size_t the_invalid_index = 3;
+  for (size_t i = 0; i <= s.length(); ++i)
+    EXPECT_EQ(i != the_invalid_index, IsValidCodePointIndex(s, i));
+  for (size_t i = 0; i <= s.length(); ++i) {
+    for (size_t j = i; j <= s.length(); ++j) {
+      ptrdiff_t offset = static_cast<ptrdiff_t>(j - i);
+      if (i <= the_invalid_index && j > the_invalid_index)
+        --offset;
+      EXPECT_EQ(offset, UTF16IndexToOffset(s, i, j));
+      EXPECT_EQ(-offset, UTF16IndexToOffset(s, j, i));
+      size_t adjusted_j = (j == the_invalid_index) ? j + 1 : j;
+      EXPECT_EQ(adjusted_j, UTF16OffsetToIndex(s, i, offset));
+      size_t adjusted_i = (i == the_invalid_index) ? i + 1 : i;
+      EXPECT_EQ(adjusted_i, UTF16OffsetToIndex(s, j, -offset));
+    }
+  }
+}
+
+}  // namespace ui