[Cronet] Retain block passed to setRequestFilterBlock on iOS.

components/cronet/ios/test/cronet_http_test.mm

 // Copyright 2015 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 <Cronet/Cronet.h>
 #import <Foundation/Foundation.h>
 
 #include <stdint.h>
 
 #include "base/logging.h"
@@ skipping 104 matching lines @@
 
 class HttpTest : public ::testing::Test {
  protected:
   HttpTest() {}
   ~HttpTest() override {}
 
   void SetUp() override {
     grpc_support::StartQuicTestServer();
     TestServer::Start();
 
+    [Cronet setRequestFilterBlock:^(NSURLRequest* request) {
+      return YES;
+    }];
     StartCronetIfNecessary(grpc_support::GetQuicTestServerPort());
+    [Cronet registerHttpProtocolHandler];
     NSURLSessionConfiguration* config =
         [NSURLSessionConfiguration ephemeralSessionConfiguration];
     [Cronet installIntoSessionConfiguration:config];
     delegate_.reset([[TestDelegate alloc] init]);
     NSURLSession* session = [NSURLSession sessionWithConfiguration:config
                                                           delegate:delegate_
                                                      delegateQueue:nil];
     // Take a reference to the session and store it so it doesn't get
     // deallocated until this object does.
     session_.reset([session retain]);
@@ skipping 12 matching lines @@
     dispatch_semaphore_wait([delegate_ semaphore],
                             dispatch_time(DISPATCH_TIME_NOW, deadline_ns));
   }
 
   base::scoped_nsobject<NSURLSession> session_;
   base::scoped_nsobject<TestDelegate> delegate_;
 };
 
 TEST_F(HttpTest, NSURLSessionReceivesData) {
   NSURL* url = net::NSURLWithGURL(GURL(grpc_support::kTestServerUrl));
+  __block BOOL block_used = NO;
   NSURLSessionDataTask* task = [session_ dataTaskWithURL:url];
+  [Cronet setRequestFilterBlock:^(NSURLRequest* request) {
+    block_used = YES;
+    EXPECT_EQ([request URL], url);
+    return YES;
+  }];
   StartDataTaskAndWaitForCompletion(task);
+  EXPECT_TRUE(block_used);
   EXPECT_EQ(nil, [delegate_ error]);
   EXPECT_STREQ(grpc_support::kHelloBodyValue,
                base::SysNSStringToUTF8([delegate_ responseBody]).c_str());
 }
 
 TEST_F(HttpTest, GetGlobalMetricsDeltas) {
   NSData* delta1 = [Cronet getGlobalMetricsDeltas];
 
   NSURL* url = net::NSURLWithGURL(GURL(grpc_support::kTestServerUrl));
   NSURLSessionDataTask* task = [session_ dataTaskWithURL:url];
@@ skipping 20 matching lines @@
       net::NSURLWithGURL(GURL(TestServer::GetEchoHeaderURL("Accept-Language")));
   NSURLSessionDataTask* task = [session_ dataTaskWithURL:url];
   StartDataTaskAndWaitForCompletion(task);
   EXPECT_EQ(nil, [delegate_ error]);
   ASSERT_STREQ("en-US,en", [[delegate_ responseBody] UTF8String]);
 }
 
 TEST_F(HttpTest, SetUserAgentIsExact) {
   NSURL* url =
       net::NSURLWithGURL(GURL(TestServer::GetEchoHeaderURL("User-Agent")));
+  [Cronet setRequestFilterBlock:nil];
   NSURLSessionDataTask* task = [session_ dataTaskWithURL:url];
   StartDataTaskAndWaitForCompletion(task);
   EXPECT_EQ(nil, [delegate_ error]);
   EXPECT_STREQ(kUserAgent, [[delegate_ responseBody] UTF8String]);
 }
 
+TEST_F(HttpTest, FilterOutRequest) {
+  NSURL* url =
+      net::NSURLWithGURL(GURL(TestServer::GetEchoHeaderURL("User-Agent")));
+  __block BOOL block_used = NO;
+  NSURLSessionDataTask* task = [session_ dataTaskWithURL:url];
+  [Cronet setRequestFilterBlock:^(NSURLRequest* request) {
+    block_used = YES;
+    EXPECT_EQ([request URL], url);
+    return NO;
+  }];
+  StartDataTaskAndWaitForCompletion(task);
+  EXPECT_TRUE(block_used);
+  EXPECT_EQ(nil, [delegate_ error]);
+  EXPECT_STRNE(kUserAgent,

[kapishnikov, 2016/11/16 17:58:53]

nit: We can make this assert stronger by using 'containsString' instead of
strict equality. It is just in case if in the future we prepend something to
kUserAgent by mistake. Something like:

EXPECT_FALSE([[delegate_ responseBody] containsString:[NSString   
stringWithCString:kUserAgent ...]);

[mef, 2016/11/16 18:11:11]

Done.

+               base::SysNSStringToUTF8([delegate_ responseBody]).c_str());
+  EXPECT_TRUE([[delegate_ responseBody] containsString:@"CFNetwork"]);
+}
+
 }  // namespace cronet