Created an interface for DownloadFile, for use in unit tests.

content/browser/download/mock_download_file.cc

+// Copyright (c) 2011 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 "content/browser/download/mock_download_file.h"
+
+#include "content/browser/download/download_create_info.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+MockDownloadFile::StatisticsRecorder::StatisticsRecorder() {
+}
+
+MockDownloadFile::StatisticsRecorder::~StatisticsRecorder() {
+}
+
+void MockDownloadFile::StatisticsRecorder::Record(StatisticsIndex index) {
+  Add(index, 1);
+}
+
+void MockDownloadFile::StatisticsRecorder::Add(StatisticsIndex index,
+                                               int count) {
+  map_[index] = map_[index] + count;
+}
+
+int MockDownloadFile::StatisticsRecorder::Count(StatisticsIndex index) {
+  if (map_.find(index) == map_.end())
+    return 0;
+  return map_[index];
+}
+
+MockDownloadFile::MockDownloadFile(
+    const DownloadCreateInfo* info,
+    const DownloadRequestHandle& request_handle,
+    DownloadManager* download_manager,
+    StatisticsRecorder* recorder)
+        : id_(info->download_id),
+          request_handle_(request_handle),
+          download_manager_(download_manager),
+          recorder_(recorder),
+          rename_count_(0),
+          in_progress_(true) {
+}
+
+MockDownloadFile::~MockDownloadFile() {
+}
+
+net::Error MockDownloadFile::Initialize(bool calculate_hash) {
+  in_progress_ = true;
+  if (recorder_)
+    recorder_->Record(StatisticsRecorder::STAT_INITIALIZE);
+  return net::OK;
+}
+
+net::Error MockDownloadFile::AppendDataToFile(
+    const char* data, size_t data_len) {
+  data_.append(data, data_len);
+  if (recorder_) {
+    recorder_->Record(StatisticsRecorder::STAT_APPEND);
+    recorder_->Add(StatisticsRecorder::STAT_BYTES, data_len);
+  }
+  return net::OK;
+}
+
+net::Error MockDownloadFile::Rename(const FilePath& full_path) {
+    EXPECT_LT(rename_count_, expected_rename_path_list_.size());
+    EXPECT_STREQ(expected_rename_path_list_[rename_count_].value().c_str(),
+                 full_path.value().c_str());
+    ++rename_count_;
+    if (recorder_)
+      recorder_->Record(StatisticsRecorder::STAT_RENAME);
+    return net::OK;
+}
+
+void MockDownloadFile::Detach() {
+  if (recorder_)
+    recorder_->Record(StatisticsRecorder::STAT_DETACH);
+}
+
+void MockDownloadFile::Cancel() {
+  in_progress_ = false;
+  if (recorder_)
+    recorder_->Record(StatisticsRecorder::STAT_CANCEL);
+}
+
+void MockDownloadFile::Finish() {
+  in_progress_ = false;
+  if (recorder_)
+    recorder_->Record(StatisticsRecorder::STAT_FINISH);
+}
+
+void MockDownloadFile::AnnotateWithSourceInformation() {
+}
+
+FilePath MockDownloadFile::FullPath() const {
+  return FilePath();
+}
+
+bool MockDownloadFile::InProgress() const {
+  return in_progress_;
+}
+
+int64 MockDownloadFile::BytesSoFar() const {
+  return data_.length();
+}
+
+bool MockDownloadFile::GetSha256Hash(std::string* hash) {
+  return false;
+}
+
+// DownloadFileInterface implementation.
+void MockDownloadFile::CancelDownloadRequest() {
+}
+
+int MockDownloadFile::Id() const {
+  return id_.local();
+}
+
+DownloadManager* MockDownloadFile::GetDownloadManager() {
+  return download_manager_;
+}
+
+const DownloadId& MockDownloadFile::GlobalId() const {
+  return id_;
+}
+
+std::string MockDownloadFile::DebugString() const {
+  return "";
+}
+
+void MockDownloadFile::SetExpectedPath(size_t index, const FilePath& path) {
+  if (expected_rename_path_list_.size() < index + 1)
+    expected_rename_path_list_.resize(index + 1);
+  expected_rename_path_list_[index] = path;
+}