Unify the two overridden DownloadManagers used by Background Fetch

content/browser/background_fetch/background_fetch_test_base.cc

Index: content/browser/background_fetch/background_fetch_test_base.cc
diff --git a/content/browser/background_fetch/background_fetch_test_base.cc b/content/browser/background_fetch/background_fetch_test_base.cc
index 2ecb64dbcea82c980aaa53a78fb03b319d6221a6..161e67072e640ca32f389e882127afe8a2bfe932 100644
--- a/content/browser/background_fetch/background_fetch_test_base.cc
+++ b/content/browser/background_fetch/background_fetch_test_base.cc
@@ -5,15 +5,27 @@
 #include "content/browser/background_fetch/background_fetch_test_base.h"
 
 #include <stdint.h>
+#include <memory>
+#include <utility>
 
 #include "base/bind.h"
 #include "base/callback.h"
+#include "base/files/file_util.h"
+#include "base/files/scoped_temp_dir.h"
+#include "base/guid.h"
 #include "base/logging.h"
+#include "base/memory/weak_ptr.h"
 #include "base/run_loop.h"
+#include "base/time/time.h"
 #include "content/browser/background_fetch/background_fetch_registration_id.h"
 #include "content/browser/service_worker/service_worker_context_core.h"
 #include "content/browser/service_worker/service_worker_registration.h"
 #include "content/common/service_worker/service_worker_status_code.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/download_item.h"
+#include "content/public/browser/download_url_parameters.h"
+#include "content/public/test/fake_download_item.h"
+#include "content/public/test/mock_download_manager.h"
 #include "url/gurl.h"
 
 namespace content {
@@ -51,6 +63,98 @@ void DidFindServiceWorkerRegistration(
 
 }  // namespace
 
+// Faked download manager that will respond to known HTTP requests with a test-
+// defined response. See CreateRequestWithProvidedResponse().
+class BackgroundFetchTestBase::RespondingDownloadManager
+    : public MockDownloadManager {
+ public:
+  RespondingDownloadManager() : weak_ptr_factory_(this) {}
+  ~RespondingDownloadManager() override = default;
+
+  // Responds to requests to |url| with the |status_code| and |response_text|.
+  void RegisterResponse(const GURL& url,
+                        int status_code,
+                        const std::string& response_text) {
+    DCHECK_EQ(registered_responses_.count(url), 0u);
+    registered_responses_[url] = std::make_pair(status_code, response_text);
+  }
+
+  // Called when the Background Fetch system starts a download, all information
+  // for which is contained in the |params|.
+  void DownloadUrl(std::unique_ptr<DownloadUrlParameters> params) override {
+    auto iter = registered_responses_.find(params->url());
+    if (iter == registered_responses_.end())
+      return;
+
+    std::unique_ptr<FakeDownloadItem> download_item =
+        base::MakeUnique<FakeDownloadItem>();
+
+    download_item->SetURL(params->url());
+    download_item->SetUrlChain({params->url()});
+    download_item->SetState(DownloadItem::DownloadState::IN_PROGRESS);
+    download_item->SetGuid(base::GenerateGUID());
+    download_item->SetStartTime(base::Time::Now());
+
+    // Asynchronously invoke the callback set on the |params|, and then continue
+    // dealing with the response in this class.
+    BrowserThread::PostTaskAndReply(
+        BrowserThread::UI, FROM_HERE,
+        base::Bind(params->callback(), download_item.get(),
+                   DOWNLOAD_INTERRUPT_REASON_NONE),
+        base::Bind(&RespondingDownloadManager::DidStartDownload,
+                   weak_ptr_factory_.GetWeakPtr(), download_item.get()));
+
+    download_items_.push_back(std::move(download_item));
+  }
+
+ private:
+  // Called when the download has been "started" by the download manager. This
+  // is where we finish the download by sending a single update.
+  void DidStartDownload(FakeDownloadItem* download_item) {
+    auto iter = registered_responses_.find(download_item->GetURL());
+    DCHECK(iter != registered_responses_.end());
+
+    const ResponseInfo& response_info = iter->second;
+
+    download_item->SetState(DownloadItem::DownloadState::COMPLETE);
+    download_item->SetEndTime(base::Time::Now());
+
+    base::FilePath response_path;
+    if (!temp_directory_.IsValid())
+      ASSERT_TRUE(temp_directory_.CreateUniqueTempDir());
+
+    // Write the |response_info|'s response_text to a temporary file.
+    ASSERT_TRUE(base::CreateTemporaryFileInDir(temp_directory_.GetPath(),
+                                               &response_path));
+
+    ASSERT_NE(-1 /* error */,
+              base::WriteFile(response_path, response_info.second.c_str(),
+                              response_info.second.size()));
+
+    download_item->SetTargetFilePath(response_path);
+    download_item->SetReceivedBytes(response_info.second.size());
+
+    // Notify the Job Controller about the download having been updated.
+    download_item->NotifyDownloadUpdated();
+  }
+
+  using ResponseInfo =
+      std::pair<int /* status_code */, std::string /* response_text */>;
+
+  // Map of URL to the response information associated with that URL.
+  std::map<GURL, ResponseInfo> registered_responses_;
+
+  // Only used to guarantee the lifetime of the created FakeDownloadItems.
+  std::vector<std::unique_ptr<FakeDownloadItem>> download_items_;
+
+  // Temporary directory in which successfully downloaded files will be stored.
+  base::ScopedTempDir temp_directory_;
+
+  base::WeakPtrFactory<RespondingDownloadManager> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(RespondingDownloadManager);
+};
+
 BackgroundFetchTestBase::BackgroundFetchTestBase()
     : thread_bundle_(TestBrowserThreadBundle::IO_MAINLOOP),
       origin_(GURL(kTestOrigin)) {}
@@ -61,10 +165,19 @@ BackgroundFetchTestBase::~BackgroundFetchTestBase() {
 }
 
 void BackgroundFetchTestBase::SetUp() {
+  download_manager_ = new RespondingDownloadManager();
+
+  // The |download_manager_| ownership is given to the BrowserContext, and the
+  // BrowserContext will take care of deallocating it.
+  BrowserContext::SetDownloadManagerForTesting(browser_context(),
+                                               download_manager_);
+
   set_up_called_ = true;
 }
 
 void BackgroundFetchTestBase::TearDown() {
+  EXPECT_CALL(*download_manager_, Shutdown()).Times(1);
+
   service_worker_registrations_.clear();
   tear_down_called_ = true;
 }
@@ -122,4 +235,28 @@ bool BackgroundFetchTestBase::CreateRegistrationId(
   return true;
 }
 
+// Creates a ServiceWorkerFetchRequest instance for the given details and
+// provides a faked response with |status_code| and |response_text| to the
+// download manager, that will resolve the download with that information.
+ServiceWorkerFetchRequest
+BackgroundFetchTestBase::CreateRequestWithProvidedResponse(
+    const std::string& method,
+    const std::string& url_string,
+    int status_code,
+    const std::string& response_text) {
+  GURL url(url_string);
+
+  // Register the |status_code| and |response_text| with the download manager.
+  download_manager_->RegisterResponse(GURL(url_string), status_code,
+                                      response_text);
+
+  // Create a ServiceWorkerFetchRequest request with the same information.
+  return ServiceWorkerFetchRequest(url, method, ServiceWorkerHeaderMap(),
+                                   Referrer(), false /* is_reload */);
+}
+
+MockDownloadManager* BackgroundFetchTestBase::download_manager() {
+  return download_manager_;
+}
+
 }  // namespace content