Introduce a helper for OPENFILENAME struct to make certain logic testable.

ui/base/win/open_file_name_win_unittest.cc

Index: ui/base/win/open_file_name_win_unittest.cc
diff --git a/ui/base/win/open_file_name_win_unittest.cc b/ui/base/win/open_file_name_win_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..5c9fefb3406d12174501e71dfaeaa58c861abf39
--- /dev/null
+++ b/ui/base/win/open_file_name_win_unittest.cc
@@ -0,0 +1,137 @@
+// Copyright (c) 2014 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/win/open_file_name_win.h"
+
+#include "base/files/file_path.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+const HWND kHwnd = reinterpret_cast<HWND>(0xDEADBEEF);
+const DWORD kFlags = OFN_OVERWRITEPROMPT | OFN_EXPLORER | OFN_ENABLESIZING;
+
+void SetResult(const base::string16& result, ui::win::OpenFileName* ofn) {
+  EXPECT_GT(ofn->Get()->nMaxFile, result.size());
+  if (ofn->Get()->nMaxFile > result.size()) {
+    if (!result.size()) {
+      ofn->Get()->lpstrFile[0] = 0;
+    } else {
+      // Because the result has embedded nulls, we must memcpy.
+      memcpy(ofn->Get()->lpstrFile,
+             result.c_str(),
+             (result.size() + 1) * sizeof(result[0]));
+    }
+  }
+}
+
+}  // namespace
+
+TEST(OpenFileNameTest, Initialization) {
+  ui::win::OpenFileName ofn(kHwnd, kFlags);
+  EXPECT_EQ(kHwnd, ofn.Get()->hwndOwner);
+  EXPECT_EQ(kFlags, ofn.Get()->Flags);
+  EXPECT_EQ(sizeof(OPENFILENAME), ofn.Get()->lStructSize);
+  ASSERT_TRUE(ofn.Get()->lpstrFile);
+  ASSERT_GT(ofn.Get()->nMaxFile, 0u);
+  EXPECT_EQ(0, ofn.Get()->lpstrFile[0]);
+}
+
+TEST(OpenFileNameTest, SetInitialSelection) {
+  const base::FilePath kDirectory(L"C:\\directory\\child_directory");
+  const base::FilePath kFile(L"file_name.ext");
+  ui::win::OpenFileName ofn(kHwnd, kFlags);
+  ofn.SetInitialSelection(kDirectory, kFile);
+  EXPECT_EQ(kDirectory, base::FilePath(ofn.Get()->lpstrInitialDir));
+  EXPECT_EQ(kFile, base::FilePath(ofn.Get()->lpstrFile));
+
+  ofn.SetInitialSelection(kDirectory, base::FilePath());
+  EXPECT_EQ(kDirectory, base::FilePath(ofn.Get()->lpstrInitialDir));
+  // Filename buffer will still be a valid pointer, to receive a result.
+  ASSERT_TRUE(ofn.Get()->lpstrFile);
+  EXPECT_EQ(base::FilePath(), base::FilePath(ofn.Get()->lpstrFile));
+
+  ofn.SetInitialSelection(base::FilePath(), base::FilePath());
+  // No initial directory will lead to a NULL buffer.
+  ASSERT_FALSE(ofn.Get()->lpstrInitialDir);
+  ASSERT_TRUE(ofn.Get()->lpstrFile);
+  EXPECT_EQ(base::FilePath(), base::FilePath(ofn.Get()->lpstrFile));
+
+  // Make sure that both values are cleared when directory is missing.
+  ofn.SetInitialSelection(kDirectory, kFile);
+  EXPECT_EQ(kDirectory, base::FilePath(ofn.Get()->lpstrInitialDir));
+  EXPECT_EQ(kFile, base::FilePath(ofn.Get()->lpstrFile));
+  ofn.SetInitialSelection(base::FilePath(), base::FilePath());
+  ASSERT_FALSE(ofn.Get()->lpstrInitialDir);
+  ASSERT_TRUE(ofn.Get()->lpstrFile);
+  EXPECT_EQ(base::FilePath(), base::FilePath(ofn.Get()->lpstrFile));
+
+  // File is ignored in absence of a directory.
+  ofn.SetInitialSelection(base::FilePath(), kFile);
+  ASSERT_FALSE(ofn.Get()->lpstrInitialDir);
+  ASSERT_TRUE(ofn.Get()->lpstrFile);
+  EXPECT_EQ(base::FilePath(), base::FilePath(ofn.Get()->lpstrFile));
+}
+
+TEST(OpenFileNameTest, GetSingleResult) {
+  const base::string16 kNull(L"\0", 1);
+  ui::win::OpenFileName ofn(kHwnd, kFlags);
+  base::FilePath result;
+
+  SetResult(L"C:\\dir\\file" + kNull, &ofn);
+  result = ofn.GetSingleResult();
+  EXPECT_EQ(base::FilePath(L"C:\\dir\\file"), result);
+
+  SetResult(L"C:\\dir"+ kNull + L"file" + kNull, &ofn);
+  result = ofn.GetSingleResult();
+  EXPECT_EQ(base::FilePath(L"C:\\dir\\file"), result);
+
+  SetResult(L"C:\\dir"+ kNull + L"file"+ kNull + L"otherfile"+ kNull, &ofn);
+  result = ofn.GetSingleResult();
+  EXPECT_EQ(base::FilePath(), result);
+
+  SetResult(L"", &ofn);
+  result = ofn.GetSingleResult();
+  EXPECT_EQ(base::FilePath(), result);
+}
+
+TEST(OpenFileNameTest, GetResult) {
+  const base::string16 kNull(L"\0", 1);
+
+  ui::win::OpenFileName ofn(kHwnd, kFlags);
+  base::FilePath directory;
+  std::vector<base::FilePath> filenames;
+
+  SetResult(L"C:\\dir\\file" + kNull, &ofn);
+  ofn.GetResult(&directory, &filenames);
+  EXPECT_EQ(base::FilePath(L"C:\\dir"), directory);
+  ASSERT_EQ(1u, filenames.size());
+  EXPECT_EQ(base::FilePath(L"file"), filenames[0]);
+
+  directory.clear();
+  filenames.clear();
+
+  SetResult(L"C:\\dir" + kNull + L"file" + kNull, &ofn);
+  ofn.GetResult(&directory, &filenames);
+  EXPECT_EQ(base::FilePath(L"C:\\dir"), directory);
+  ASSERT_EQ(1u, filenames.size());
+  EXPECT_EQ(base::FilePath(L"file"), filenames[0]);
+
+  directory.clear();
+  filenames.clear();
+
+  SetResult(L"C:\\dir" + kNull + L"file" + kNull + L"otherfile" + kNull, &ofn);
+  ofn.GetResult(&directory, &filenames);
+  EXPECT_EQ(base::FilePath(L"C:\\dir"), directory);
+  ASSERT_EQ(2u, filenames.size());
+  EXPECT_EQ(base::FilePath(L"file"), filenames[0]);
+  EXPECT_EQ(base::FilePath(L"otherfile"), filenames[1]);
+
+  directory.clear();
+  filenames.clear();
+
+  SetResult(L"", &ofn);
+  ofn.GetResult(&directory, &filenames);
+  EXPECT_EQ(base::FilePath(), directory);
+  ASSERT_EQ(0u, filenames.size());
+}