Create the BackgroundFetchBatchManager and initiate a download.

content/browser/background_fetch/background_fetch_batch_manager_unittest.cc

+// Copyright 2017 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/background_fetch/background_fetch_batch_manager.h"
+
+#include "base/bind_helpers.h"
+#include "base/callback_helpers.h"
+#include "base/run_loop.h"
+#include "content/browser/background_fetch/fetch_request.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/test/mock_download_manager.h"
+#include "content/public/test/test_browser_context.h"
+#include "content/public/test/test_browser_thread_bundle.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+
+const char kOrigin[] = "https://example.com/";
+const char kBatchUid[] = "TestRequestUid";
+constexpr int64_t kServiceWorkerRegistrationId = 9001;
+const char kTestUrl[] = "http://www.example.com/example.html";
+
+}  // namespace
+
+namespace content {
+
+class BackgroundFetchBatchManagerTest : public ::testing::Test {
+ public:
+  BackgroundFetchBatchManagerTest()
+      : batch_manager_(
+            &browser_context_,
+            BrowserContext::GetDefaultStoragePartition(&browser_context_)),
+        download_manager_(new content::MockDownloadManager()) {

[Peter Beverloo, 2017/02/23 12:14:56]

nit: drop `content::`

[harkness, 2017/02/23 17:08:41]

Done.

+    BrowserContext::SetDownloadManagerForTesting(&browser_context_,
+                                                 download_manager_);
+  }
+  ~BackgroundFetchBatchManagerTest() override {}
+
+  void ProcessBatch(const std::string& batch_uid,
+                    const std::vector<FetchRequest>& requests) {
+    base::RunLoop run_loop;
+    BrowserThread::PostTask(
+        BrowserThread::IO, FROM_HERE,
+        base::Bind(&BackgroundFetchBatchManagerTest::ProcessBatchOnIO,
+                   base::Unretained(this), batch_uid, requests,
+                   run_loop.QuitClosure()));
+    run_loop.Run();
+  }
+
+  void ProcessBatchOnIO(const std::string& batch_uid,
+                        const std::vector<FetchRequest>& requests,
+                        const base::Closure& closure) {
+    batch_manager_.ProcessBatch(batch_uid, requests);
+    BrowserThread::PostTask(BrowserThread::UI, FROM_HERE, closure);
+  }
+
+  BackgroundFetchBatchManager* GetBatchManager() { return &batch_manager_; }

[Peter Beverloo, 2017/02/23 12:14:59]

nit: batch_manager() const { .. }

[harkness, 2017/02/23 17:08:41]

Done.

+  MockDownloadManager* GetDownloadManager() { return download_manager_; }

[Peter Beverloo, 2017/02/23 12:14:56]

nit: download_manager() const { .. }

[harkness, 2017/02/23 17:08:41]

Done.

+
+ private:
+  TestBrowserThreadBundle thread_bundle_;
+  TestBrowserContext browser_context_;
+  BackgroundFetchBatchManager batch_manager_;
+  MockDownloadManager* download_manager_;
+};
+
+TEST_F(BackgroundFetchBatchManagerTest, StartDownload) {
+  FetchRequest request(url::Origin(GURL(kOrigin)), GURL(kTestUrl),
+                       kServiceWorkerRegistrationId, kBatchUid);

[Peter Beverloo, 2017/02/23 12:14:56]

What is a "uid"?

[harkness, 2017/02/23 17:08:41]

An imprecise statement of a guid. I've updated.

+  std::vector<FetchRequest> requests;
+  requests.push_back(request);
+
+  EXPECT_CALL(*(GetDownloadManager()),
+              DownloadUrlMock(::testing::Pointee(::testing::Property(
+                  &DownloadUrlParameters::url, GURL(kTestUrl)))))
+      .Times(1);
+  ProcessBatch(kBatchUid, requests);
+}
+
+}  // namespace content