Replace usage of single-threaded SequencedWorkerPool with a base::Thread in image_fetcher_unittest.…

ios/chrome/browser/net/image_fetcher_unittest.mm

 // Copyright 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.
 
 #import "ios/chrome/browser/net/image_fetcher.h"
 
 #import <UIKit/UIKit.h>
 
 #include "base/ios/ios_util.h"
 #include "base/mac/scoped_block.h"
 #include "base/macros.h"
+#include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/run_loop.h"
+#include "base/threading/thread.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "build/build_config.h"
 #include "net/http/http_response_headers.h"
 #include "net/url_request/test_url_fetcher_factory.h"
 #include "net/url_request/url_request_test_util.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/platform_test.h"
 
 namespace {
 
@@ skipping 36 matching lines @@
     48,1,0,157,1,42,1,0,1,0,3,0,52,37,164,0,3,112,0,254,251,253,80,0
 };
 
 static const char kTestUrl[] = "http://www.img.com";
 
 static const char kWEBPHeaderResponse[] =
     "HTTP/1.1 200 OK\0Content-type: image/webp\0\0";
 
 }  // namespace
 
-// TODO(ios): remove the static_cast<UIImage*>(nil) once all the bots have
-// Xcode 6.0 or later installed, http://crbug.com/440857
-
 class ImageFetcherTest : public PlatformTest {
  protected:
   ImageFetcherTest()
-      : pool_(new base::SequencedWorkerPool(1,
-                                            "TestPool",
-                                            base::TaskPriority::USER_VISIBLE)),
-        image_fetcher_(new ImageFetcher(pool_)),
-        result_(nil),
-        called_(false) {
-    callback_.reset(
-        [^(const GURL& original_url, int http_response_code, NSData* data) {
-            result_ = [UIImage imageWithData:data];
-            called_ = true;
-        } copy]);
+      : worker_thread_("TestThread"),
+        callback_([^(const GURL& original_url,
+                     int http_response_code,
+                     NSData * data) {
+          result_ = [UIImage imageWithData:data];
+          called_ = true;
+        } copy]) {
+    worker_thread_.Start();
+
+    image_fetcher_ =
+        base::MakeUnique<ImageFetcher>(worker_thread_.task_runner());
     image_fetcher_->SetRequestContextGetter(
         new net::TestURLRequestContextGetter(
             base::ThreadTaskRunnerHandle::Get()));
   }
 
-  ~ImageFetcherTest() override { pool_->Shutdown(); }
-
   net::TestURLFetcher* SetupFetcher() {
     image_fetcher_->StartDownload(GURL(kTestUrl), callback_);
-    EXPECT_EQ(static_cast<UIImage*>(nil), result_);
+    EXPECT_EQ(nil, result_);
     EXPECT_EQ(false, called_);
     net::TestURLFetcher* fetcher = factory_.GetFetcherByID(0);
     DCHECK(fetcher);
     DCHECK(fetcher->delegate());
     return fetcher;
   }
 
+  // Message loop for the main test thread.
   base::MessageLoop loop_;
+
+  // Worker thread used for ImageFetcher's asynchronous work.
+  base::Thread worker_thread_;
+
   base::mac::ScopedBlock<ImageFetchedCallback> callback_;
   net::TestURLFetcherFactory factory_;
-  scoped_refptr<base::SequencedWorkerPool> pool_;
   std::unique_ptr<ImageFetcher> image_fetcher_;
-  UIImage* result_;
-  bool called_;
+  UIImage* result_ = nil;
+  bool called_ = false;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ImageFetcherTest);
 };
 
 TEST_F(ImageFetcherTest, TestError) {
   net::TestURLFetcher* fetcher = SetupFetcher();
   fetcher->set_response_code(404);
   fetcher->delegate()->OnURLFetchComplete(fetcher);
-  EXPECT_EQ(static_cast<UIImage*>(nil), result_);
+  EXPECT_EQ(nil, result_);
   EXPECT_TRUE(called_);
 }
 
 TEST_F(ImageFetcherTest, TestJpg) {
   net::TestURLFetcher* fetcher = SetupFetcher();
   fetcher->set_response_code(200);
   fetcher->SetResponseString(std::string((char*)kJPGImage, sizeof(kJPGImage)));
   fetcher->delegate()->OnURLFetchComplete(fetcher);
-  EXPECT_NE(static_cast<UIImage*>(nil), result_);
+  EXPECT_NE(nil, result_);
   EXPECT_TRUE(called_);
 }
 
 TEST_F(ImageFetcherTest, TestPng) {
   net::TestURLFetcher* fetcher = SetupFetcher();
   fetcher->set_response_code(200);
   fetcher->SetResponseString(std::string((char*)kPNGImage, sizeof(kPNGImage)));
   fetcher->delegate()->OnURLFetchComplete(fetcher);
-  EXPECT_NE(static_cast<UIImage*>(nil), result_);
+  EXPECT_NE(nil, result_);
   EXPECT_TRUE(called_);
 }
 
 TEST_F(ImageFetcherTest, TestGoodWebP) {
 // TODO(droger): This test fails on iOS 9 x64 devices. http://crbug.com/523235
 #if defined(OS_IOS) && defined(ARCH_CPU_ARM64) && !TARGET_IPHONE_SIMULATOR
   if (base::ios::IsRunningOnIOS9OrLater())
     return;
 #endif
   net::TestURLFetcher* fetcher = SetupFetcher();
   fetcher->set_response_code(200);
   fetcher->SetResponseString(
       std::string((char*)kWEBPImage, sizeof(kWEBPImage)));
   scoped_refptr<net::HttpResponseHeaders> headers(new net::HttpResponseHeaders(
       std::string(kWEBPHeaderResponse, arraysize(kWEBPHeaderResponse))));
   fetcher->set_response_headers(headers);
   fetcher->delegate()->OnURLFetchComplete(fetcher);
-  pool_->FlushForTesting();
+  worker_thread_.FlushForTesting();
   base::RunLoop().RunUntilIdle();
-  EXPECT_NE(static_cast<UIImage*>(nil), result_);
+  EXPECT_NE(nil, result_);
   EXPECT_TRUE(called_);
 }
 
 TEST_F(ImageFetcherTest, TestBadWebP) {
   net::TestURLFetcher* fetcher = SetupFetcher();
   fetcher->set_response_code(200);
   fetcher->SetResponseString("This is not a valid WebP image");
   scoped_refptr<net::HttpResponseHeaders> headers(new net::HttpResponseHeaders(
       std::string(kWEBPHeaderResponse, arraysize(kWEBPHeaderResponse))));
   fetcher->set_response_headers(headers);
   fetcher->delegate()->OnURLFetchComplete(fetcher);
-  pool_->FlushForTesting();
+  worker_thread_.FlushForTesting();
   base::RunLoop().RunUntilIdle();
-  EXPECT_EQ(static_cast<UIImage*>(nil), result_);
+  EXPECT_EQ(nil, result_);
   EXPECT_TRUE(called_);
 }
 
 TEST_F(ImageFetcherTest, DeleteDuringWebPDecoding) {
   net::TestURLFetcher* fetcher = SetupFetcher();
   fetcher->set_response_code(200);
   fetcher->SetResponseString(
       std::string((char*)kWEBPImage, sizeof(kWEBPImage)));
   scoped_refptr<net::HttpResponseHeaders> headers(new net::HttpResponseHeaders(
       std::string(kWEBPHeaderResponse, arraysize(kWEBPHeaderResponse))));
   fetcher->set_response_headers(headers);
   fetcher->delegate()->OnURLFetchComplete(fetcher);
   // Delete the image fetcher, and check that the callback is not called.
   image_fetcher_.reset();
-  pool_->FlushForTesting();
+  worker_thread_.FlushForTesting();
   base::RunLoop().RunUntilIdle();
-  EXPECT_EQ(static_cast<UIImage*>(nil), result_);
+  EXPECT_EQ(nil, result_);
   EXPECT_FALSE(called_);
 }
 
 TEST_F(ImageFetcherTest, TestCallbacksNotCalledDuringDeletion) {
   image_fetcher_->StartDownload(GURL(kTestUrl), callback_);
   image_fetcher_.reset();
   EXPECT_FALSE(called_);
 }