Extract ReadAllData testing utility.

The method will be used more, so to avoid duplicate it, extract it to the
test_util.

BUG=127129
TEST=Ran unit_tests

Review URL: https://chromiumcodereview.appspot.com/14842003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@198090 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 56 insertions, 87 deletions

diff --git a/chrome/browser/chromeos/drive/drive_file_stream_reader_unittest.cc b/chrome/browser/chromeos/drive/drive_file_stream_reader_unittest.cc
index fdf58e1..a7e5984 100644
--- a/chrome/browser/chromeos/drive/drive_file_stream_reader_unittest.cc
+++ b/chrome/browser/chromeos/drive/drive_file_stream_reader_unittest.cc
@@ -11,6 +11,7 @@
 #include "base/files/file_path.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/message_loop.h"
+#include "base/rand_util.h"
 #include "base/sequenced_task_runner.h"
 #include "base/threading/thread.h"
 #include "chrome/browser/chromeos/drive/fake_file_system.h"
@@ -38,26 +39,6 @@ void IncrementCallback(int* num_called) {
   ++*num_called;
 }
 
-// Reads all data from |reader| and copies to |content|. Returns net::Error
-// code.
-int ReadAllData(ReaderProxy* proxy, std::string* content) {
-  const int kBufferSize = 10;
-  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kBufferSize));
-
-  // Read repeatedly, until it is finished.
-  while (true) {
-    net::TestCompletionCallback callback;
-    int result = proxy->Read(buffer.get(), kBufferSize, callback.callback());
-    result = callback.GetResult(result);
-    if (result <= 0) {
-      // An error or EOF is found. Note that net::OK is 0.
-      return result;
-    }
-
-    content->append(buffer->data(), result);
-  }
-}
-
 }  // namespace
 
 class LocalReaderProxyTest : public ::testing::Test {
@@ -101,7 +82,7 @@ TEST_F(LocalReaderProxyTest, Read) {
 
   // Make sure the read contant is as same as the file.
   std::string content;
-  ASSERT_EQ(net::OK, ReadAllData(&proxy, &content));
+  ASSERT_EQ(net::OK, test_util::ReadAllData(&proxy, &content));
   EXPECT_EQ(file_content_, content);
 }
 
@@ -122,7 +103,7 @@ TEST_F(LocalReaderProxyTest, ReadWithLimit) {
 
   // Make sure the read contant is as same as the file.
   std::string content;
-  ASSERT_EQ(net::OK, ReadAllData(&proxy, &content));
+  ASSERT_EQ(net::OK, test_util::ReadAllData(&proxy, &content));
   EXPECT_EQ(expected_content, content);
 }
 
@@ -381,13 +362,8 @@ class DriveFileStreamReaderTest : public ::testing::Test {
 TEST_F(DriveFileStreamReaderTest, Read) {
   const base::FilePath kDriveFile =
       util::GetDriveMyDriveRootPath().AppendASCII("File 1.txt");
-  net::TestCompletionCallback callback;
-  const int kBufferSize = 3;
-  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kBufferSize));
-
   // Create the reader, and initialize it.
   // In this case, the file is not yet locally cached.
-
   scoped_ptr<DriveFileStreamReader> reader(new DriveFileStreamReader(
       GetFileSystemGetter(),
       worker_thread_->message_loop_proxy()));
@@ -405,17 +381,11 @@ TEST_F(DriveFileStreamReaderTest, Read) {
   EXPECT_EQ(FILE_ERROR_OK, error);
   ASSERT_TRUE(entry);
   EXPECT_TRUE(reader->IsInitialized());
+  size_t content_size = entry->file_info().size();
 
   // Read data from the reader.
-  size_t content_size = entry->file_info().size();
   std::string first_content;
-  while (first_content.size() < content_size) {
-    int result = reader->Read(buffer.get(), kBufferSize, callback.callback());
-    result = callback.GetResult(result);
-    ASSERT_GT(result, 0);
-    first_content.append(buffer->data(), result);
-  }
-
+  ASSERT_EQ(net::OK, test_util::ReadAllData(reader.get(), &first_content));
   EXPECT_EQ(content_size, first_content.size());
 
   // Create second instance and initialize it.
@@ -439,17 +409,11 @@ TEST_F(DriveFileStreamReaderTest, Read) {
   EXPECT_TRUE(reader->IsInitialized());
 
   // The size should be same.
-  EXPECT_EQ(content_size,
-            static_cast<size_t>(entry->file_info().size()));
+  EXPECT_EQ(content_size, static_cast<size_t>(entry->file_info().size()));
 
   // Read data from the reader, again.
   std::string second_content;
-  while (second_content.size() < content_size) {
-    int result = reader->Read(buffer.get(), kBufferSize, callback.callback());
-    result = callback.GetResult(result);
-    ASSERT_GT(result, 0);
-    second_content.append(buffer->data(), result);
-  }
+  ASSERT_EQ(net::OK, test_util::ReadAllData(reader.get(), &second_content));
 
   // The same content is expected.
   EXPECT_EQ(first_content, second_content);
diff --git a/chrome/browser/chromeos/drive/drive_url_request_job_unittest.cc b/chrome/browser/chromeos/drive/drive_url_request_job_unittest.cc
index 9dce8ad..e9fe663 100644
--- a/chrome/browser/chromeos/drive/drive_url_request_job_unittest.cc
+++ b/chrome/browser/chromeos/drive/drive_url_request_job_unittest.cc
@@ -13,6 +13,7 @@
 #include "chrome/browser/chromeos/drive/drive_file_stream_reader.h"
 #include "chrome/browser/chromeos/drive/fake_file_system.h"
 #include "chrome/browser/chromeos/drive/file_system_util.h"
+#include "chrome/browser/chromeos/drive/test_util.h"
 #include "chrome/browser/google_apis/fake_drive_service.h"
 #include "chrome/browser/google_apis/task_util.h"
 #include "chrome/browser/google_apis/test_util.h"
@@ -182,30 +183,15 @@ class DriveURLRequestJobTest : public testing::Test {
             google_apis::test_util::CreateCopyResultCallback(
                 &error, &entry)));
     message_loop_.Run();
-    if (error != FILE_ERROR_OK)
+    if (error != FILE_ERROR_OK || !entry)
       return false;
 
     // Read data from the reader.
-    size_t content_size = entry->file_info().size();
     std::string content;
-    const int kBufferSize = 100;
-    scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kBufferSize));
-    while (content.size() < content_size) {
-      net::TestCompletionCallback callback;
-      int result = reader->Read(buffer.get(), kBufferSize, callback.callback());
-      result = callback.GetResult(result);
-      if (result < 0) {
-        // An error is found.
-        return false;
-      }
-      if (result == 0) {
-        // EOF is found.
-        break;
-      }
-      content.append(buffer->data(), result);
-    }
-
-    if (content_size != content.size())
+    if (test_util::ReadAllData(reader.get(), &content) != net::OK)
+      return false;
+
+    if (static_cast<size_t>(entry->file_info().size()) != content.size())
       return false;
 
     *out_content = content;
diff --git a/chrome/browser/chromeos/drive/file_reader_unittest.cc b/chrome/browser/chromeos/drive/file_reader_unittest.cc
index dbc0690..c25a246 100644
--- a/chrome/browser/chromeos/drive/file_reader_unittest.cc
+++ b/chrome/browser/chromeos/drive/file_reader_unittest.cc
@@ -14,6 +14,7 @@
 #include "base/message_loop.h"
 #include "base/rand_util.h"
 #include "base/threading/thread.h"
+#include "chrome/browser/chromeos/drive/test_util.h"
 #include "chrome/browser/google_apis/test_util.h"
 #include "net/base/io_buffer.h"
 #include "net/base/test_completion_callback.h"
@@ -23,30 +24,21 @@ namespace drive {
 namespace util {
 namespace {
 
-// Reads all the contents from |file_reader| and stores into |out_content|.
-// Returns net::Error code.
-int ReadAllData(FileReader* file_reader, std::string* out_content) {
-  const int kBufferSize = 100;
-  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kBufferSize));
-
-  std::string content;
-  while (true) {
-    net::TestCompletionCallback callback;
-    file_reader->Read(buffer.get(), kBufferSize, callback.callback());
-    int result = callback.WaitForResult();
-    if (result < 0) {
-      return result;
-    }
-    if (result == 0) {
-      // Quit the loop at EOF.
-      break;
-    }
-    content.append(buffer->data(), result);
+// An adapter to use test_util::ReadAllData.
+class FileReaderAdapter {
+ public:
+  explicit FileReaderAdapter(FileReader* reader) : reader_(reader) {}
+  int Read(net::IOBuffer* buffer,
+           int buffer_length,
+           const net::CompletionCallback& callback) {
+    reader_->Read(buffer, buffer_length, callback);
+    // As FileReader::Read always works asynchronously, return ERR_IO_PENDING.
+    return net::ERR_IO_PENDING;
   }
 
-  *out_content = content;
-  return net::OK;
-}
+ private:
+  FileReader* reader_;
+};
 
 }  // namespace
 
@@ -92,8 +84,9 @@ TEST_F(DriveFileReaderTest, FullRead) {
   file_reader_->Open(test_file, 0, callback.callback());
   ASSERT_EQ(net::OK, callback.WaitForResult());
 
+  FileReaderAdapter adapter(file_reader_.get());
   std::string content;
-  ASSERT_EQ(net::OK, ReadAllData(file_reader_.get(), &content));
+  ASSERT_EQ(net::OK, test_util::ReadAllData(&adapter, &content));
   EXPECT_EQ(expected_content, content);
 }
 
@@ -111,8 +104,9 @@ TEST_F(DriveFileReaderTest, OpenWithOffset) {
       test_file, static_cast<int64>(offset), callback.callback());
   ASSERT_EQ(net::OK, callback.WaitForResult());
 
+  FileReaderAdapter adapter(file_reader_.get());
   std::string content;
-  ASSERT_EQ(net::OK, ReadAllData(file_reader_.get(), &content));
+  ASSERT_EQ(net::OK, test_util::ReadAllData(&adapter, &content));
   EXPECT_EQ(expected_content, content);
 }
 
diff --git a/chrome/browser/chromeos/drive/test_util.h b/chrome/browser/chromeos/drive/test_util.h
index 67e8ace..0823e11 100644
--- a/chrome/browser/chromeos/drive/test_util.h
+++ b/chrome/browser/chromeos/drive/test_util.h
@@ -8,6 +8,13 @@
 #include <string>
 
 #include "chrome/browser/google_apis/test_util.h"
+#include "net/base/completion_callback.h"
+#include "net/base/io_buffer.h"
+#include "net/base/test_completion_callback.h"
+
+namespace net {
+class IOBuffer;
+}  // namespace net
 
 namespace drive {
 
@@ -54,6 +61,24 @@ struct DestroyHelperForTests {
   }
 };
 
+// Reads all the data from |reader| and copies to |content|. Returns net::Error
+// code.
+template<typename Reader>
+int ReadAllData(Reader* reader, std::string* content) {
+  const int kBufferSize = 10;
+  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kBufferSize));
+  while (true) {
+    net::TestCompletionCallback callback;
+    int result = reader->Read(buffer.get(), kBufferSize, callback.callback());
+    result = callback.GetResult(result);
+    if (result <= 0) {
+      // Found an error or EOF. Return it. Note: net::OK is 0.
+      return result;
+    }
+    content->append(buffer->data(), result);
+  }
+}
+
 }  // namespace test_util
 }  // namespace drive