Handle early pause, cancel for parallel requests.

content/browser/download/parallel_download_job_unittest.cc

Index: content/browser/download/parallel_download_job_unittest.cc
diff --git a/content/browser/download/parallel_download_job_unittest.cc b/content/browser/download/parallel_download_job_unittest.cc
index 394da4163942f0276df755a842ca346cacf66c4c..efdb618cfadcd7df65faea915b968ad8f6013210 100644
--- a/content/browser/download/parallel_download_job_unittest.cc
+++ b/content/browser/download/parallel_download_job_unittest.cc
@@ -31,6 +31,37 @@ class MockDownloadRequestHandle : public DownloadRequestHandleInterface {
   MOCK_CONST_METHOD0(DebugString, std::string());
 };
 
+class DownloadWorkerForTest : public DownloadWorker {
+ public:
+  DownloadWorkerForTest(DownloadWorker::Delegate* delegate,
+                        int64_t offset,
+                        int64_t length)
+      : DownloadWorker(delegate, offset, length) {}
+
+  // For passing in a mock request handle.
+  void MakeResponseReady() {
+    UrlDownloader::Delegate* delegate =
+        static_cast<UrlDownloader::Delegate*>(this);
+
+    std::unique_ptr<DownloadCreateInfo> create_info =
+        base::MakeUnique<DownloadCreateInfo>();
+    std::unique_ptr<MockDownloadRequestHandle> mock_handle =
+        base::MakeUnique<MockDownloadRequestHandle>();
+    mock_request_handle_ = mock_handle.get();
+    create_info->request_handle = std::move(mock_handle);
+    delegate->OnUrlDownloaderStarted(
+        std::move(create_info), std::unique_ptr<ByteStreamReader>(),
+        DownloadUrlParameters::OnStartedCallback());
+  }
+
+  MockDownloadRequestHandle* mock_request_handle() const {
+    return mock_request_handle_;
+  }
+
+ private:
+  MockDownloadRequestHandle* mock_request_handle_ = nullptr;
+};
+
 }  // namespace
 
 class ParallelDownloadJobForTest : public ParallelDownloadJob {
@@ -45,16 +76,25 @@ class ParallelDownloadJobForTest : public ParallelDownloadJob {
                             create_info),
         request_count_(request_count) {}
 
+  const std::vector<DownloadWorkerForTest*>& mock_workers() {
+    return mock_workers_;
+  }
+
   void CreateRequest(int64_t offset, int64_t length) override {
-    fake_tasks_.push_back(std::pair<int64_t, int64_t>(offset, length));
+    std::unique_ptr<DownloadWorkerForTest> mock_worker =
+        base::MakeUnique<DownloadWorkerForTest>(this, offset, length);
+    mock_workers_.push_back(mock_worker.get());
+
+    DCHECK(workers_.find(offset) == workers_.end());
+    workers_[offset] = std::move(mock_worker);
   }
 
   int GetParallelRequestCount() const override { return request_count_; }
 
-  std::vector<std::pair<int64_t, int64_t>> fake_tasks_;
-
  private:
+  std::vector<DownloadWorkerForTest*> mock_workers_;
   int request_count_;
+
   DISALLOW_COPY_AND_ASSIGN(ParallelDownloadJobForTest);
 };
 
@@ -70,23 +110,41 @@ class ParallelDownloadJobTest : public testing::Test {
     DownloadCreateInfo info;
     info.offset = offset;
     info.total_bytes = content_length;
+    std::unique_ptr<MockDownloadRequestHandle> request_handle =
+        base::MakeUnique<MockDownloadRequestHandle>();
+    mock_request_handle_ = request_handle.get();
     job_ = base::MakeUnique<ParallelDownloadJobForTest>(
-        download_item_.get(), base::MakeUnique<MockDownloadRequestHandle>(),
-        info, request_count);
+        download_item_.get(), std::move(request_handle), info, request_count);
   }
 
   void DestroyParallelJob() {
     job_.reset();
     download_item_.reset();
     item_delegate_.reset();
+    mock_request_handle_ = nullptr;
   }
 
   void BuildParallelRequests() { job_->BuildParallelRequests(); }
 
+  // Simulate all workers establishing byte streams.
+  void PushAllByteStream() {
+    for (auto& worker : job_->workers_)
+      job_->OnByteStreamReady(worker.second.get(),
+                              std::unique_ptr<ByteStreamReader>());
+  }
+
+  void VerifyWorker(int64_t offset, int64_t length) const {
+    EXPECT_TRUE(job_->workers_.find(offset) != job_->workers_.end());
+    EXPECT_EQ(offset, job_->workers_[offset]->offset());
+    EXPECT_EQ(length, job_->workers_[offset]->length());
+  }
+
   content::TestBrowserThreadBundle browser_threads_;
   std::unique_ptr<DownloadItemImplDelegate> item_delegate_;
   std::unique_ptr<MockDownloadItemImpl> download_item_;
   std::unique_ptr<ParallelDownloadJobForTest> job_;
+  // Request handle for the original request.
+  MockDownloadRequestHandle* mock_request_handle_;
 };
 
 // Test if parallel requests can be built correctly for a new download.
@@ -96,10 +154,8 @@ TEST_F(ParallelDownloadJobTest, CreateNewDownloadRequests) {
   // Task 1:  Range:50-, for 50 bytes.
   CreateParallelJob(0, 100, DownloadItem::ReceivedSlices(), 2);
   BuildParallelRequests();
-  EXPECT_EQ(1, static_cast<int>(job_->fake_tasks_.size()));
-  EXPECT_EQ(50, job_->fake_tasks_[0].first);
-  EXPECT_EQ(0, job_->fake_tasks_[0].second);
-  job_->fake_tasks_.clear();
+  EXPECT_EQ(1, static_cast<int>(job_->mock_workers().size()));
+  VerifyWorker(50, 0);
   DestroyParallelJob();
 
   // Totally 3 requests for 100 bytes.
@@ -108,12 +164,9 @@ TEST_F(ParallelDownloadJobTest, CreateNewDownloadRequests) {
   // Task 2:  Range:66-, for 34 bytes.
   CreateParallelJob(0, 100, DownloadItem::ReceivedSlices(), 3);
   BuildParallelRequests();
-  EXPECT_EQ(2, static_cast<int>(job_->fake_tasks_.size()));
-  EXPECT_EQ(33, job_->fake_tasks_[0].first);
-  EXPECT_EQ(33, job_->fake_tasks_[0].second);
-  EXPECT_EQ(66, job_->fake_tasks_[1].first);
-  EXPECT_EQ(0, job_->fake_tasks_[1].second);
-  job_->fake_tasks_.clear();
+  EXPECT_EQ(2, static_cast<int>(job_->mock_workers().size()));
+  VerifyWorker(33, 33);
+  VerifyWorker(66, 0);
   DestroyParallelJob();
 
   // Totally 3 requests for 100 bytes. Start from the 17th byte.
@@ -122,34 +175,31 @@ TEST_F(ParallelDownloadJobTest, CreateNewDownloadRequests) {
   // Task 2:  Range:71-99, for 29 bytes.
   CreateParallelJob(17, 83, DownloadItem::ReceivedSlices(), 3);
   BuildParallelRequests();
-  EXPECT_EQ(2, static_cast<int>(job_->fake_tasks_.size()));
-  EXPECT_EQ(44, job_->fake_tasks_[0].first);
-  EXPECT_EQ(27, job_->fake_tasks_[0].second);
-  EXPECT_EQ(71, job_->fake_tasks_[1].first);
-  EXPECT_EQ(0, job_->fake_tasks_[1].second);
-  job_->fake_tasks_.clear();
+  EXPECT_EQ(2, static_cast<int>(job_->mock_workers().size()));
+  VerifyWorker(44, 27);
+  VerifyWorker(71, 0);
   DestroyParallelJob();
 
   // Less than 2 requests, do nothing.
   CreateParallelJob(0, 100, DownloadItem::ReceivedSlices(), 1);
   BuildParallelRequests();
-  EXPECT_TRUE(job_->fake_tasks_.empty());
+  EXPECT_TRUE(job_->mock_workers().empty());
   DestroyParallelJob();
 
   CreateParallelJob(0, 100, DownloadItem::ReceivedSlices(), 0);
   BuildParallelRequests();
-  EXPECT_TRUE(job_->fake_tasks_.empty());
+  EXPECT_TRUE(job_->mock_workers().empty());
   DestroyParallelJob();
 
   // Content-length is 0, do nothing.
   CreateParallelJob(100, 0, DownloadItem::ReceivedSlices(), 3);
   BuildParallelRequests();
-  EXPECT_TRUE(job_->fake_tasks_.empty());
+  EXPECT_TRUE(job_->mock_workers().empty());
   DestroyParallelJob();
 
   CreateParallelJob(0, 0, DownloadItem::ReceivedSlices(), 3);
   BuildParallelRequests();
-  EXPECT_TRUE(job_->fake_tasks_.empty());
+  EXPECT_TRUE(job_->mock_workers().empty());
   DestroyParallelJob();
 
   // 2 bytes left for 3 additional requests. Only 1 are built.
@@ -157,10 +207,103 @@ TEST_F(ParallelDownloadJobTest, CreateNewDownloadRequests) {
   // Task 1:  Range:99-, for 1 byte.
   CreateParallelJob(98, 2, DownloadItem::ReceivedSlices(), 4);
   BuildParallelRequests();
-  EXPECT_EQ(1, static_cast<int>(job_->fake_tasks_.size()));
-  EXPECT_EQ(99, job_->fake_tasks_[0].first);
-  EXPECT_EQ(0, job_->fake_tasks_[0].second);
-  job_->fake_tasks_.clear();
+  EXPECT_EQ(1, static_cast<int>(job_->mock_workers().size()));
+  VerifyWorker(99, 0);
+  DestroyParallelJob();
+}
+
+// Pause, cancel, resume can be called before or after the worker establish
+// the byte stream.
+// These tests ensure the states consistency between the job and workers.
+
+// Ensure cancel before building the requests will result in workers being
+// canceled.
+TEST_F(ParallelDownloadJobTest, EarlyCancelBeforeBuildRequests) {
+  CreateParallelJob(0, 100, DownloadItem::ReceivedSlices(), 2);
+  EXPECT_CALL(*mock_request_handle_, CancelRequest());
+
+  // Job is canceled before building parallel requests.
+  job_->Cancel(true);
+  EXPECT_TRUE(job_->is_canceled());
+
+  BuildParallelRequests();
+  VerifyWorker(50, 0);
+  for (auto* worker : job_->mock_workers()) {
+    worker->MakeResponseReady();
+    EXPECT_CALL(*worker->mock_request_handle(), CancelRequest());
+  }
+  PushAllByteStream();
+  DestroyParallelJob();
+}
+
+// Ensure cancel before adding the byte stream will result in workers being
+// canceled.
+TEST_F(ParallelDownloadJobTest, EarlyCancelBeforeByteStreamReady) {
+  CreateParallelJob(0, 100, DownloadItem::ReceivedSlices(), 2);
+  EXPECT_CALL(*mock_request_handle_, CancelRequest());
+
+  BuildParallelRequests();
+  VerifyWorker(50, 0);
+
+  // Job is canceled after building parallel requests and before byte streams
+  // are added to the file sink.
+  job_->Cancel(true);
+  EXPECT_TRUE(job_->is_canceled());
+
+  for (auto* worker : job_->mock_workers()) {
+    worker->MakeResponseReady();
+    EXPECT_CALL(*worker->mock_request_handle(), CancelRequest());
+  }
+  PushAllByteStream();
+  DestroyParallelJob();
+}
+
+// Ensure pause before building the requests will result in workers being
+// paused.
+TEST_F(ParallelDownloadJobTest, EarlyPauseBeforeBuildRequests) {
+  CreateParallelJob(0, 100, DownloadItem::ReceivedSlices(), 2);
+  EXPECT_CALL(*mock_request_handle_, PauseRequest());
+
+  // Job is paused before building parallel requests.
+  job_->Pause();
+  EXPECT_TRUE(job_->is_paused());
+
+  BuildParallelRequests();
+  VerifyWorker(50, 0);
+  for (auto* worker : job_->mock_workers()) {
+    worker->MakeResponseReady();
+    EXPECT_CALL(*worker->mock_request_handle(), PauseRequest());
+    // MockDownloadItemImpl doesn't have DownloadFile, so the worker will call
+    // cancel after failed to add the byte stream to file sink.
+    // TODO(xingliu): Consider pass a mock download file into this test.
+    EXPECT_CALL(*worker->mock_request_handle(), CancelRequest());
+  }
+
+  PushAllByteStream();
+  DestroyParallelJob();
+}
+
+// Ensure pause before adding the byte stream will result in workers being
+// paused.
+TEST_F(ParallelDownloadJobTest, EarlyPauseBeforeByteStreamReady) {
+  CreateParallelJob(0, 100, DownloadItem::ReceivedSlices(), 2);
+  EXPECT_CALL(*mock_request_handle_, PauseRequest());
+
+  BuildParallelRequests();
+  VerifyWorker(50, 0);
+
+  // Job is paused after building parallel requests and before adding the byte
+  // stream to the file sink.
+  job_->Pause();
+  EXPECT_TRUE(job_->is_paused());
+
+  for (auto* worker : job_->mock_workers()) {
+    worker->MakeResponseReady();
+    EXPECT_CALL(*worker->mock_request_handle(), PauseRequest());
+    EXPECT_CALL(*worker->mock_request_handle(), CancelRequest());
+  }
+
+  PushAllByteStream();
   DestroyParallelJob();
 }