Added new ReadFileToString API with a max_size argument

base/files/file_util_proxy_unittest.cc

 // Copyright (c) 2012 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 "base/files/file_util_proxy.h"
 
 #include <map>
 
 #include "base/bind.h"
 #include "base/file_util.h"
@@ skipping 203 matching lines @@
 
   // Make sure the written data can be read from the returned path.
   std::string data;
   EXPECT_TRUE(ReadFileToString(path_, &data));
   EXPECT_EQ("test", data);
 
   // Make sure we can & do delete the created file to prevent leaks on the bots.
   EXPECT_TRUE(base::DeleteFile(path_, false));
 }
 
+TEST_F(FileUtilProxyTest, ReadFileToString) {

[Andrew T Wilson (Slow), 2014/02/11 10:27:12]

I think this code should live in base/file_util_unittest.cc, not in
file_util_proxy_unittest.cc.

[kaliamoorthi, 2014/02/11 16:29:16]

Done.

+  const char kTestData[] = "0123";
+  std::string data;
+
+  ASSERT_EQ(4, file_util::WriteFile(test_path(), kTestData, 4));
+
+  EXPECT_TRUE(ReadFileToString(test_path(), &data));
+  EXPECT_EQ(kTestData, data);
+
+  data.clear();
+  EXPECT_FALSE(ReadFileToString(test_path(), &data, 0));
+  EXPECT_EQ(data.length(), (size_t)0);
+
+  data.clear();
+  EXPECT_FALSE(ReadFileToString(test_path(), &data, 2));
+  EXPECT_EQ(data.length(), (size_t)0);
+
+  data.clear();
+  EXPECT_FALSE(ReadFileToString(test_path(), &data, 3));
+  EXPECT_EQ(data.length(), (size_t)0);
+
+  data.clear();
+  EXPECT_TRUE(ReadFileToString(test_path(), &data, 4));
+  EXPECT_EQ("0123", data);
+
+  data.clear();
+  EXPECT_TRUE(ReadFileToString(test_path(), &data, 6));
+  EXPECT_EQ("0123", data);
+
+  EXPECT_TRUE(ReadFileToString(test_path(), NULL, 6));
+
+  EXPECT_TRUE(ReadFileToString(test_path(), NULL));
+
+  // Make sure we can & do delete the created file to prevent leaks on the bots.
+  EXPECT_TRUE(base::DeleteFile(test_path(), false));

[Andrew T Wilson (Slow), 2014/02/11 10:27:12]

Add another call to make sure trying to read a deleted file fails:

EXPECT_FALSE(ReadFileToString(test_path(), NULL));

+}
+
 TEST_F(FileUtilProxyTest, GetFileInfo_File) {
   // Setup.
   ASSERT_EQ(4, file_util::WriteFile(test_path(), "test", 4));
   File::Info expected_info;
   GetFileInfo(test_path(), &expected_info);
 
   // Run.
   FileUtilProxy::GetFileInfo(
       file_task_runner(),
       test_path(),
@@ skipping 167 matching lines @@
   char buffer[53];
   EXPECT_EQ(53, base::ReadFile(test_path(), buffer, 53));
   int i = 0;
   for (; i < 10; ++i)
     EXPECT_EQ(kTestData[i], buffer[i]);
   for (; i < 53; ++i)
     EXPECT_EQ(0, buffer[i]);
 }
 
 }  // namespace base