[ui/base;css] adding string template expression replacement

ui/base/template_expressions_unittest.cc

Index: ui/base/template_expressions_unittest.cc
diff --git a/ui/base/template_expressions_unittest.cc b/ui/base/template_expressions_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f5c363144ff0390a7b893b0d9ef17f397a0511b0
--- /dev/null
+++ b/ui/base/template_expressions_unittest.cc
@@ -0,0 +1,36 @@
+// Copyright 2015 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/template_expressions.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace ui {
+
+TEST(TemplateExpressionsTest, ReplaceTemplateExpressionsPieces) {
+  std::map<base::StringPiece, std::string> substitutions;
+  substitutions["test"] = "word";
+  substitutions["5"] = "number";
+  substitutions[""] = "blank";
+
+  EXPECT_EQ(ReplaceTemplateExpressions("${}", substitutions), "blank");
+  EXPECT_EQ(ReplaceTemplateExpressions("", substitutions), "");
+  EXPECT_EQ(ReplaceTemplateExpressions("${test}", substitutions), "word");
+  EXPECT_EQ(ReplaceTemplateExpressions("${5} ", substitutions), "number ");
+  EXPECT_EQ(
+      ReplaceTemplateExpressions("multiple: ${test}, ${5}.", substitutions),
+      "multiple: word, number.");
+}
+
+TEST(TemplateExpressionsTest,
+     ReplaceTemplateExpressionsConsecutiveDollarSignsPieces) {
+  std::map<base::StringPiece, std::string> substitutions;
+  substitutions["a"] = "x";
+  EXPECT_EQ(ReplaceTemplateExpressions("$ $$ $$$", substitutions), "$ $$ $$$");
+  EXPECT_EQ(ReplaceTemplateExpressions("$${a}", substitutions), "$x");
+  EXPECT_EQ(ReplaceTemplateExpressions("$$${a}", substitutions), "$$x");
+  EXPECT_EQ(ReplaceTemplateExpressions("$12", substitutions), "$12");
+}
+
+}  // namespace ui