Clean up and simplify how we deal with filename extensions on Windows. Allow...

chrome/browser/views/shell_dialogs_win_unittest.cc

+// Copyright (c) 2010 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/browser/shell_dialogs.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+TEST(AppendExtensionIfNeeded, EndingInPeriod_ExtensionAppended) {
+  const std::wstring filename = L"sample.txt.";
+  const std::wstring filter_selected = L"*.txt";
+  const std::wstring suggested_ext = L"txt";
+
+  const std::wstring actual_filename = AppendExtensionIfNeeded(filename,
+      filter_selected, suggested_ext);
+
+  ASSERT_EQ(L"sample.txt.txt", actual_filename);
+}
+
+TEST(AppendExtensionIfNeeded, UnknownMimeType_ExtensionAppended) {
+  const std::wstring filename = L"sample.unknown-mime-type";
+  const std::wstring filter_selected = L"*.txt";
+  const std::wstring suggested_ext = L"txt";
+
+  const std::wstring actual_filename = AppendExtensionIfNeeded(filename,
+      filter_selected, suggested_ext);
+
+  ASSERT_EQ(L"sample.unknown-mime-type.txt", actual_filename);
+}
+
+TEST(AppendExtensionIfNeeded, RecognizableMimeType_NoExtensionAppended) {
+  const std::wstring filename = L"sample.html";
+  const std::wstring filter_selected = L"*.txt";
+  const std::wstring suggested_ext = L"txt";
+
+  const std::wstring actual_filename = AppendExtensionIfNeeded(filename,
+      filter_selected, suggested_ext);
+
+  ASSERT_EQ(L"sample.html", actual_filename);
+}
+
+TEST(AppendExtensionIfNeeded, OnlyPeriods_ExtensionAppended) {
+  const std::wstring filename = L"...";
+  const std::wstring filter_selected = L"*.txt";
+  const std::wstring suggested_ext = L"txt";
+
+  const std::wstring actual_filename = AppendExtensionIfNeeded(filename,
+      filter_selected, suggested_ext);
+
+  ASSERT_EQ(L"...txt", actual_filename);
+}
+
+TEST(AppendExtensionIfNeeded, EqualToExtension_ExtensionAppended) {
+  const std::wstring filename = L"txt";
+  const std::wstring filter_selected = L"*.txt";
+  const std::wstring suggested_ext = L"txt";
+
+  const std::wstring actual_filename = AppendExtensionIfNeeded(filename,
+      filter_selected, suggested_ext);
+
+  ASSERT_EQ(L"txt.txt", actual_filename);
+}
+
+TEST(AppendExtensionIfNeeded, AllFilesFilter_NoExtensionAppended) {
+  const std::wstring filename = L"sample.unknown-mime-type";
+  const std::wstring filter_selected = L"*.*";
+  const std::wstring suggested_ext;
+
+  const std::wstring actual_filename = AppendExtensionIfNeeded(filename,
+      filter_selected, suggested_ext);
+
+  ASSERT_EQ(L"sample.unknown-mime-type", actual_filename);
+}