Optimize URLPrefix::BestURLPrefix

components/omnibox/browser/url_prefix_unittest.cc

+// Copyright 2016 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 "components/omnibox/browser/url_prefix.h"
+
+#include "base/strings/utf_string_conversions.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+struct TestCase {
+  TestCase(const char* text,
+           const char* prefix_suffix,
+           const char* expected_prefix)
+      : text(base::ASCIIToUTF16(text)),
+        prefix_suffix(base::ASCIIToUTF16(prefix_suffix)),
+        expected_prefix(base::ASCIIToUTF16(expected_prefix)) {}
+  base::string16 text;
+  base::string16 prefix_suffix;
+  base::string16 expected_prefix;
+};
+}  // namespace
+
+TEST(URLPrefix, BestURLPrefix) {
+  const TestCase test_cases[] = {
+      // Lowercase test cases with empty prefix suffix.
+      TestCase("https://www.yandex.ru", "", "https://www."),
+      TestCase("http://www.yandex.ru", "", "http://www."),
+      TestCase("ftp://www.yandex.ru", "", "ftp://www."),
+      TestCase("https://yandex.ru", "", "https://"),
+      TestCase("http://yandex.ru", "", "http://"),
+      TestCase("ftp://yandex.ru", "", "ftp://"),
+      // Mixed case test cases with empty prefix suffix.

[Peter Kasting, 2016/04/23 19:51:30]

Nit: Blank line above this, as well as the two comment lines below.

[Alexander Yashkin, 2016/04/24 07:18:50]

Done.

+      TestCase("HTTPS://www.yandex.ru", "", "https://www."),
+      TestCase("http://WWW.yandex.ru", "", "http://www."),
+      // Cases with non empty prefix suffix.
+      TestCase("http://www.yandex.ru", "yan", "http://www."),
+      TestCase("https://www.yandex.ru", "YaN", "https://www."),
+      // Prefix suffix does not match.
+      TestCase("https://www.yandex.ru", "index", ""),
+  };
+
+  for (const TestCase& test_case : test_cases) {
+    const URLPrefix* prefix =
+        URLPrefix::BestURLPrefix(test_case.text, test_case.prefix_suffix);
+    if (test_case.expected_prefix.empty()) {
+      EXPECT_FALSE(prefix);
+    } else {
+      ASSERT_TRUE(prefix);
+      EXPECT_EQ(test_case.expected_prefix, prefix->prefix);
+    }
+  }
+}