Create StringOrdinal to allow placement of strings in sorted lists

chrome/common/string_index_unittest.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 "chrome/common/string_index.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+
+class StringIndexTest: public testing::Test {
+ protected:
+  StringIndex string_index_;
+};
+
+TEST_F(StringIndexTest, CreateStringBetweenSingleDigit) {
+  EXPECT_EQ("C", string_index_.CreateStringBetween("B", "D"));
+  EXPECT_EQ("C", string_index_.CreateStringBetween("B", "E"));
+  EXPECT_EQ("D", string_index_.CreateStringBetween("B", "F"));
+
+  EXPECT_EQ("BM", string_index_.CreateStringBetween("B","C"));
+  EXPECT_EQ("CM", string_index_.CreateStringBetween("C","D"));
+}
+
+TEST_F(StringIndexTest, CreateStringBetweenEnd) {
+  EXPECT_EQ("ZM", string_index_.CreateStringBetween("Z", ""));
+  EXPECT_EQ("ZZM", string_index_.CreateStringBetween("ZZ", ""));
+  EXPECT_EQ("ZZZYM", string_index_.CreateStringBetween("ZZZY",""));
+  EXPECT_EQ("ZL", string_index_.CreateStringBetween("YY",""));
+}
+
+TEST_F(StringIndexTest, CreateStringBetweenStart) {
+  EXPECT_EQ("AM", string_index_.CreateStringBetween("", "B"));
+  EXPECT_EQ("AM", string_index_.CreateStringBetween("", "BB"));
+  EXPECT_EQ("AN", string_index_.CreateStringBetween("", "BC"));
+  EXPECT_EQ("AN", string_index_.CreateStringBetween("", "BD"));
+}
+
+TEST_F(StringIndexTest, CreateStringBetweenLastDigitTheSame) {
+  EXPECT_EQ("AN", string_index_.CreateStringBetween("AB", "BB"));
+  EXPECT_EQ("BN", string_index_.CreateStringBetween("BB", "CB"));
+  EXPECT_EQ("BBN", string_index_.CreateStringBetween("BBB", "BCB"));
+}