[Offline Pages] Turn Offliner::Cancel into an async operation to resolve conflicting assumptions

chrome/browser/android/offline_pages/prerendering_offliner_unittest.cc

 // Copyright 2016 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 "chrome/browser/android/offline_pages/prerendering_offliner.h"
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/run_loop.h"
@@ skipping 154 matching lines @@
   ~PrerenderingOfflinerTest() override;
 
   void SetUp() override;
 
   Profile* profile() { return &profile_; }
   PrerenderingOffliner* offliner() const { return offliner_.get(); }
   Offliner::CompletionCallback const callback() {
     return base::Bind(&PrerenderingOfflinerTest::OnCompletion,
                       base::Unretained(this));
   }
+  Offliner::CancelCallback const cancel_callback() {
+    return base::Bind(&PrerenderingOfflinerTest::OnCancel,
+                      base::Unretained(this));
+  }
 
   bool SaveInProgress() const { return model_->mock_saving(); }
   MockPrerenderingLoader* loader() { return loader_; }
   MockOfflinePageModel* model() { return model_; }
   bool completion_callback_called() { return completion_callback_called_; }
   Offliner::RequestStatus request_status() { return request_status_; }
   OfflinerPolicy* policy() { return policy_; }
+  bool cancel_callback_called() { return cancel_callback_called_; }
 
  private:
   void OnCompletion(const SavePageRequest& request,
                     Offliner::RequestStatus status);
+  void OnCancel(int64_t offline_id);
 
   content::TestBrowserThreadBundle thread_bundle_;
   TestingProfile profile_;
   std::unique_ptr<PrerenderingOffliner> offliner_;
   // Not owned.
   MockPrerenderingLoader* loader_;
   MockOfflinePageModel* model_;
   bool completion_callback_called_;
+  bool cancel_callback_called_;
   Offliner::RequestStatus request_status_;
   OfflinerPolicy* policy_;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderingOfflinerTest);
 };
 
 PrerenderingOfflinerTest::PrerenderingOfflinerTest()
     : thread_bundle_(content::TestBrowserThreadBundle::IO_MAINLOOP),
       completion_callback_called_(false),
+      cancel_callback_called_(false),
       request_status_(Offliner::RequestStatus::UNKNOWN) {}
 
 PrerenderingOfflinerTest::~PrerenderingOfflinerTest() {}
 
 void PrerenderingOfflinerTest::SetUp() {
   model_ = new MockOfflinePageModel();
   policy_ = new OfflinerPolicy();
   offliner_.reset(new PrerenderingOffliner(profile(), policy_, model_));
   std::unique_ptr<MockPrerenderingLoader> mock_loader(
       new MockPrerenderingLoader(nullptr));
   loader_ = mock_loader.get();
   offliner_->SetLoaderForTesting(std::move(mock_loader));
 }
 
 void PrerenderingOfflinerTest::OnCompletion(const SavePageRequest& request,
                                             Offliner::RequestStatus status) {
   DCHECK(!completion_callback_called_);  // Expect single callback per request.
   completion_callback_called_ = true;
   request_status_ = status;
 }
 
+void PrerenderingOfflinerTest::OnCancel(int64_t offline_id) {
+  DCHECK(!cancel_callback_called_);
+  cancel_callback_called_ = true;
+}
+
 TEST_F(PrerenderingOfflinerTest, LoadAndSaveBadUrl) {
   base::Time creation_time = base::Time::Now();
   SavePageRequest request(
       kRequestId, kFileUrl, kClientId, creation_time, kUserRequested);
   EXPECT_FALSE(offliner()->LoadAndSave(request, callback()));
   EXPECT_TRUE(loader()->IsIdle());
 }
 
 TEST_F(PrerenderingOfflinerTest, LoadAndSavePrerenderingDisabled) {
   base::Time creation_time = base::Time::Now();
@@ skipping 44 matching lines @@
   EXPECT_FALSE(SaveInProgress());
 }
 
 TEST_F(PrerenderingOfflinerTest, CancelWhenLoading) {
   base::Time creation_time = base::Time::Now();
   SavePageRequest request(
       kRequestId, kHttpUrl, kClientId, creation_time, kUserRequested);
   EXPECT_TRUE(offliner()->LoadAndSave(request, callback()));
   EXPECT_FALSE(loader()->IsIdle());
 
-  offliner()->Cancel();
+  offliner()->Cancel(cancel_callback());
+  PumpLoop();
+  EXPECT_TRUE(cancel_callback_called());
   EXPECT_TRUE(loader()->IsIdle());
 }
 
 TEST_F(PrerenderingOfflinerTest, CancelWhenLoaded) {
   base::Time creation_time = base::Time::Now();
   SavePageRequest request(
       kRequestId, kHttpUrl, kClientId, creation_time, kUserRequested);
   EXPECT_TRUE(offliner()->LoadAndSave(request, callback()));
   EXPECT_FALSE(loader()->IsIdle());
   EXPECT_EQ(Offliner::RequestStatus::UNKNOWN, request_status());
 
   loader()->CompleteLoadingAsLoaded();
   PumpLoop();
   EXPECT_FALSE(completion_callback_called());
   EXPECT_TRUE(loader()->IsLoaded());
   EXPECT_TRUE(SaveInProgress());
 
-  offliner()->Cancel();
+  offliner()->Cancel(cancel_callback());
   PumpLoop();
   EXPECT_FALSE(completion_callback_called());
+  EXPECT_TRUE(cancel_callback_called());
   EXPECT_FALSE(loader()->IsLoaded());
   // Note: save still in progress since it does not support canceling.
   EXPECT_TRUE(SaveInProgress());
 
   // Subsequent save callback causes no harm (no crash and no callback).
   model()->CompleteSavingAsArchiveCreationFailed();
   PumpLoop();
   EXPECT_FALSE(completion_callback_called());
   EXPECT_TRUE(loader()->IsIdle());
   EXPECT_FALSE(SaveInProgress());
@@ skipping 159 matching lines @@
   base::Time creation_time = base::Time::Now();
   SavePageRequest request(kRequestId, kHttpUrl, kClientId, creation_time,
                           kUserRequested);
   EXPECT_TRUE(offliner()->LoadAndSave(request, callback()));
   loader()->set_is_lowbar_met(true);
   EXPECT_FALSE(offliner()->HandleTimeout(request));
   EXPECT_FALSE(loader()->start_snapshot_called());
 }
 
 }  // namespace offline_pages