file_util: Convert the wstring version of IsDirectoryEmpty to FilePath.

base/file_util_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 "build/build_config.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #include <shellapi.h>
 #include <shlobj.h>
@@ skipping 1604 matching lines @@
   // Note that this timestamp is divisible by two (seconds) - FAT stores
   // modification times with 2s resolution.
   ASSERT_TRUE(base::Time::FromString(L"Tue, 15 Nov 1994, 12:45:26 GMT",
               &modification_time));
   ASSERT_TRUE(file_util::SetLastModifiedTime(foobar, modification_time));
   file_util::FileInfo file_info;
   ASSERT_TRUE(file_util::GetFileInfo(foobar, &file_info));
   ASSERT_TRUE(file_info.last_modified == modification_time);
 }
 
+TEST_F(FileUtilTest, IsDirectoryEmpty) {
+  FilePath empty_dir = test_dir_.Append(FILE_PATH_LITERAL("EmptyDir"));
+
+  ASSERT_FALSE(file_util::PathExists(empty_dir));
+
+  ASSERT_TRUE(file_util::CreateDirectory(empty_dir));
+
+  EXPECT_TRUE(file_util::IsDirectoryEmpty(empty_dir));
+
+  FilePath foo(empty_dir.Append(FILE_PATH_LITERAL("foo.txt")));
+  std::string bar("baz");
+  ASSERT_TRUE(file_util::WriteFile(foo, bar.c_str(), bar.length()));
+
+  EXPECT_FALSE(file_util::IsDirectoryEmpty(empty_dir));
+}
+
 }  // namespace