net/url_request/url_request_test_util.cc

// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "net/url_request/url_request_test_util.h"

#include <memory>
#include <utility>

#include "base/check_op.h"
#include "base/compiler_specific.h"
#include "base/location.h"
#include "base/run_loop.h"
#include "base/supports_user_data.h"
#include "base/task/single_thread_task_runner.h"
#include "base/threading/thread.h"
#include "net/base/features.h"
#include "net/base/host_port_pair.h"
#include "net/cert/cert_verifier.h"
#include "net/cert/do_nothing_ct_verifier.h"
#include "net/cookies/cookie_setting_override.h"
#include "net/cookies/cookie_util.h"
#include "net/dns/mock_host_resolver.h"
#include "net/http/http_network_session.h"
#include "net/http/http_response_headers.h"
#include "net/http/http_server_properties.h"
#include "net/http/transport_security_state.h"
#include "net/proxy_resolution/configured_proxy_resolution_service.h"
#include "net/proxy_resolution/proxy_retry_info.h"
#include "net/quic/quic_context.h"
#include "net/url_request/redirect_info.h"
#include "net/url_request/static_http_user_agent_settings.h"
#include "net/url_request/url_request.h"
#include "net/url_request/url_request_context_builder.h"
#include "net/url_request/url_request_filter.h"
#include "net/url_request/url_request_job.h"
#include "net/url_request/url_request_job_factory.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace net {

namespace {

// These constants put the NetworkDelegate events of TestNetworkDelegate
// into an order. They are used in conjunction with
// |TestNetworkDelegate::next_states_| to check that we do not send
// events in the wrong order.
const int kStageBeforeURLRequest = 1 << 0;
const int kStageBeforeStartTransaction = 1 << 1;
const int kStageHeadersReceived = 1 << 2;
const int kStageBeforeRedirect = 1 << 3;
const int kStageBeforeRetry = 1 << 4;
const int kStageResponseStarted = 1 << 5;
const int kStageCompletedSuccess = 1 << 6;
const int kStageCompletedError = 1 << 7;
const int kStageURLRequestDestroyed = 1 << 8;
const int kStageDestruction = 1 << 9;

const char kTestNetworkDelegateRequestIdKey[] =
    "TestNetworkDelegateRequestIdKey";

class TestRequestId : public base::SupportsUserData::Data {
 public:
  explicit TestRequestId(int id) : id_(id) {}
  ~TestRequestId() override = default;

  int id() const { return id_; }

 private:
  const int id_;
};

}  // namespace

std::unique_ptr<URLRequestContextBuilder> CreateTestURLRequestContextBuilder() {
  auto builder = std::make_unique<URLRequestContextBuilder>();
  builder->set_host_resolver(std::make_unique<MockCachingHostResolver>(
      /*cache_invalidation_num=*/0,
      /*default_result=*/MockHostResolverBase::RuleResolver::
          GetLocalhostResult()));
  builder->set_proxy_resolution_service(
      ConfiguredProxyResolutionService::CreateDirect());
  builder->SetCertVerifier(
      CertVerifier::CreateDefault(/*cert_net_fetcher=*/nullptr));
  builder->set_ssl_config_service(std::make_unique<SSLConfigServiceDefaults>());
  builder->SetHttpAuthHandlerFactory(HttpAuthHandlerFactory::CreateDefault());
  builder->SetHttpServerProperties(std::make_unique<HttpServerProperties>());
  builder->set_quic_context(std::make_unique<QuicContext>());
  builder->SetCookieStore(std::make_unique<CookieMonster>(/*store=*/nullptr,
                                                          /*netlog=*/nullptr));
  builder->set_http_user_agent_settings(
      std::make_unique<StaticHttpUserAgentSettings>("en-us,fr", std::string()));
  return builder;
}

TestURLRequestContextGetter::TestURLRequestContextGetter(
    const scoped_refptr<base::SingleThreadTaskRunner>& network_task_runner)
    : network_task_runner_(network_task_runner) {
  DCHECK(network_task_runner_.get());
}

TestURLRequestContextGetter::TestURLRequestContextGetter(
    const scoped_refptr<base::SingleThreadTaskRunner>& network_task_runner,
    std::unique_ptr<URLRequestContext> context)
    : network_task_runner_(network_task_runner), context_(std::move(context)) {
  DCHECK(network_task_runner_.get());
}

TestURLRequestContextGetter::~TestURLRequestContextGetter() = default;

URLRequestContext* TestURLRequestContextGetter::GetURLRequestContext() {
  if (is_shut_down_)
    return nullptr;

  if (!context_.get())
    context_ = CreateTestURLRequestContextBuilder()->Build();
  return context_.get();
}

void TestURLRequestContextGetter::NotifyContextShuttingDown() {
  // This should happen before call to base NotifyContextShuttingDown() per that
  // method's doc comments.
  is_shut_down_ = true;

  URLRequestContextGetter::NotifyContextShuttingDown();
  context_ = nullptr;
}

scoped_refptr<base::SingleThreadTaskRunner>
TestURLRequestContextGetter::GetNetworkTaskRunner() const {
  return network_task_runner_;
}

const int TestDelegate::kBufferSize;

TestDelegate::TestDelegate()
    : buf_(base::MakeRefCounted<IOBufferWithSize>(kBufferSize)) {}

TestDelegate::~TestDelegate() = default;

void TestDelegate::RunUntilComplete() {
  base::RunLoop run_loop;
  on_complete_ = run_loop.QuitClosure();
  run_loop.Run();
}

void TestDelegate::RunUntilRedirect() {
  base::RunLoop run_loop;
  on_redirect_ = run_loop.QuitClosure();
  run_loop.Run();
}

void TestDelegate::RunUntilAuthRequired() {
  base::RunLoop run_loop;
  on_auth_required_ = run_loop.QuitClosure();
  run_loop.Run();
}

int TestDelegate::OnConnected(URLRequest* request,
                              const TransportInfo& info,
                              CompletionOnceCallback callback) {
  transports_.push_back(info);

  if (on_connected_run_callback_) {
    base::SingleThreadTaskRunner::GetCurrentDefault()->PostTask(
        FROM_HERE, base::BindOnce(std::move(callback), on_connected_result_));
    return net::ERR_IO_PENDING;
  }

  return on_connected_result_;
}

void TestDelegate::OnReceivedRedirect(URLRequest* request,
                                      const RedirectInfo& redirect_info,
                                      bool* defer_redirect) {
  EXPECT_TRUE(request->is_redirecting());

  redirect_info_ = redirect_info;

  received_redirect_count_++;
  if (on_redirect_) {
    *defer_redirect = true;
    std::move(on_redirect_).Run();
  } else if (cancel_in_rr_) {
    request->Cancel();
  }
}

void TestDelegate::OnAuthRequired(URLRequest* request,
                                  const AuthChallengeInfo& auth_info) {
  auth_required_ = true;
  if (on_auth_required_) {
    std::move(on_auth_required_).Run();
    return;
  }
  if (!credentials_.Empty()) {
    request->SetAuth(credentials_);
  } else {
    request->CancelAuth();
  }
}

void TestDelegate::OnSSLCertificateError(URLRequest* request,
                                         int net_error,
                                         const SSLInfo& ssl_info,
                                         bool fatal) {
  // The caller can control whether it needs all SSL requests to go through,
  // independent of any possible errors, or whether it wants SSL errors to
  // cancel the request.
  have_certificate_errors_ = true;
  certificate_errors_are_fatal_ = fatal;
  certificate_net_error_ = net_error;
  if (allow_certificate_errors_)
    request->ContinueDespiteLastError();
  else
    request->Cancel();
}

void TestDelegate::OnResponseStarted(URLRequest* request, int net_error) {
  // It doesn't make sense for the request to have IO pending at this point.
  DCHECK_NE(ERR_IO_PENDING, net_error);
  EXPECT_FALSE(request->is_redirecting());

  response_started_count_++;
  request_status_ = net_error;
  if (cancel_in_rs_) {
    request_status_ = request->Cancel();
    // Canceling |request| will cause OnResponseCompleted() to be called.
  } else if (net_error != OK) {
    request_failed_ = true;
    OnResponseCompleted(request);
  } else {
    // Initiate the first read.
    int bytes_read = request->Read(buf_.get(), kBufferSize);
    if (bytes_read >= 0)
      OnReadCompleted(request, bytes_read);
    else if (bytes_read != ERR_IO_PENDING)
      OnResponseCompleted(request);
  }
}

void TestDelegate::OnReadCompleted(URLRequest* request, int bytes_read) {
  // It doesn't make sense for the request to have IO pending at this point.
  DCHECK_NE(bytes_read, ERR_IO_PENDING);

  // If you've reached this, you've either called "RunUntilComplete"
  // If this DCHECK fails, that probably  means you've run
  // "RunUntilRedirect" or "RunUntilAuthRequired" and haven't
  // redirected/auth-challenged
  DCHECK(on_complete_);

  // If the request was cancelled in a redirect, it should not signal
  // OnReadCompleted. Note that |cancel_in_rs_| may be true due to
  // https://crbug.com/564848.
  EXPECT_FALSE(cancel_in_rr_);

  if (response_started_count_ == 0)
    received_data_before_response_ = true;

  if (bytes_read >= 0) {
    // There is data to read.
    received_bytes_count_ += bytes_read;

    // Consume the data.
    data_received_.append(buf_->data(), bytes_read);

    if (cancel_in_rd_) {
      request_status_ = request->Cancel();
      // If bytes_read is 0, won't get a notification on cancelation.
      if (bytes_read == 0) {
          std::move(on_complete_).Run();
      }
      return;
    }
  }

  // If it was not end of stream, request to read more.
  while (bytes_read > 0) {
    bytes_read = request->Read(buf_.get(), kBufferSize);
    if (bytes_read > 0) {
      data_received_.append(buf_->data(), bytes_read);
      received_bytes_count_ += bytes_read;
    }
  }

  request_status_ = bytes_read;
  if (request_status_ != ERR_IO_PENDING)
    OnResponseCompleted(request);
  else if (cancel_in_rd_pending_)
    request_status_ = request->Cancel();
}

void TestDelegate::OnResponseCompleted(URLRequest* request) {
  response_completed_ = true;
  std::move(on_complete_).Run();
}

TestNetworkDelegate::TestNetworkDelegate() = default;

TestNetworkDelegate::~TestNetworkDelegate() {
  for (auto i = next_states_.begin(); i != next_states_.end(); ++i) {
    event_order_[i->first] += "~TestNetworkDelegate\n";
    EXPECT_TRUE(i->second & kStageDestruction) << event_order_[i->first];
  }
}

bool TestNetworkDelegate::GetLoadTimingInfoBeforeRedirect(
    LoadTimingInfo* load_timing_info_before_redirect) const {
  *load_timing_info_before_redirect = load_timing_info_before_redirect_;
  return has_load_timing_info_before_redirect_;
}

void TestNetworkDelegate::InitRequestStatesIfNew(int request_id) {
  if (next_states_.find(request_id) == next_states_.end()) {
    // TODO(davidben): Although the URLRequest documentation does not allow
    // calling Cancel() before Start(), the ResourceLoader does so. URLRequest's
    // destructor also calls Cancel. Either officially support this or fix the
    // ResourceLoader code.
    next_states_[request_id] = kStageBeforeURLRequest | kStageCompletedError;
    event_order_[request_id] = "";
  }
}

int TestNetworkDelegate::OnBeforeURLRequest(URLRequest* request,
                                            CompletionOnceCallback callback,
                                            GURL* new_url) {
  int req_id = GetRequestId(request);
  InitRequestStatesIfNew(req_id);
  event_order_[req_id] += "OnBeforeURLRequest\n";
  EXPECT_TRUE(next_states_[req_id] & kStageBeforeURLRequest) <<
      event_order_[req_id];
  next_states_[req_id] =
      kStageBeforeStartTransaction |
      kStageResponseStarted |  // data: URLs do not trigger sending headers
      kStageBeforeRedirect |   // a delegate can trigger a redirection
      kStageCompletedError;    // request canceled by delegate
  created_requests_++;
  return OK;
}

int TestNetworkDelegate::OnBeforeStartTransaction(
    URLRequest* request,
    const HttpRequestHeaders& headers,
    OnBeforeStartTransactionCallback callback) {
  if (before_start_transaction_fails_)
    return ERR_FAILED;

  int req_id = GetRequestId(request);
  InitRequestStatesIfNew(req_id);
  event_order_[req_id] += "OnBeforeStartTransaction\n";
  EXPECT_TRUE(next_states_[req_id] & kStageBeforeStartTransaction)
      << event_order_[req_id];
  next_states_[req_id] =
      kStageHeadersReceived | kStageCompletedError | kStageBeforeRedirect;
  before_start_transaction_count_++;
  return OK;
}

int TestNetworkDelegate::OnHeadersReceived(
    URLRequest* request,
    CompletionOnceCallback callback,
    const HttpResponseHeaders* original_response_headers,
    scoped_refptr<HttpResponseHeaders>* override_response_headers,
    const IPEndPoint& endpoint,
    std::optional<GURL>* preserve_fragment_on_redirect_url) {
  EXPECT_FALSE(preserve_fragment_on_redirect_url->has_value());
  int req_id = GetRequestId(request);
  bool is_first_response =
      event_order_[req_id].find("OnHeadersReceived\n") == std::string::npos;
  event_order_[req_id] += "OnHeadersReceived\n";
  InitRequestStatesIfNew(req_id);
  EXPECT_TRUE(next_states_[req_id] & kStageHeadersReceived) <<
      event_order_[req_id];
  next_states_[req_id] = kStageBeforeRedirect | kStageBeforeRetry |
                         kStageResponseStarted |
                         kStageCompletedError;  // e.g. proxy resolution problem

  // Basic authentication sends a second request from the URLRequestHttpJob
  // layer before the URLRequest reports that a response has started.
  next_states_[req_id] |= kStageBeforeStartTransaction;

  if (!redirect_on_headers_received_url_.is_empty()) {
    *override_response_headers = base::MakeRefCounted<HttpResponseHeaders>(
        original_response_headers->raw_headers());
    (*override_response_headers)->ReplaceStatusLine("HTTP/1.1 302 Found");
    (*override_response_headers)->RemoveHeader("Location");
    (*override_response_headers)
        ->AddHeader("Location", redirect_on_headers_received_url_.spec());

    redirect_on_headers_received_url_ = GURL();

    // Since both values are std::optionals, can just copy this over.
    *preserve_fragment_on_redirect_url = preserve_fragment_on_redirect_url_;
  } else if (add_header_to_first_response_ && is_first_response) {
    *override_response_headers = base::MakeRefCounted<HttpResponseHeaders>(
        original_response_headers->raw_headers());
    (*override_response_headers)
        ->AddHeader("X-Network-Delegate", "Greetings, planet");
  }

  headers_received_count_++;
  return OK;
}

void TestNetworkDelegate::OnBeforeRedirect(URLRequest* request,
                                           const GURL& new_location) {
  load_timing_info_before_redirect_ = LoadTimingInfo();
  request->GetLoadTimingInfo(&load_timing_info_before_redirect_);
  has_load_timing_info_before_redirect_ = true;
  EXPECT_FALSE(load_timing_info_before_redirect_.request_start_time.is_null());
  EXPECT_FALSE(load_timing_info_before_redirect_.request_start.is_null());

  int req_id = GetRequestId(request);
  InitRequestStatesIfNew(req_id);
  event_order_[req_id] += "OnBeforeRedirect\n";
  EXPECT_TRUE(next_states_[req_id] & kStageBeforeRedirect) <<
      event_order_[req_id];
  next_states_[req_id] =
      kStageBeforeURLRequest |        // HTTP redirects trigger this.
      kStageBeforeStartTransaction |  // Redirects from the network delegate do
                                      // not
                                      // trigger onBeforeURLRequest.
      kStageCompletedError;

  // A redirect can lead to a file or a data URL. In this case, we do not send
  // headers.
  next_states_[req_id] |= kStageResponseStarted;
}

void TestNetworkDelegate::OnBeforeRetry(URLRequest* request) {
  int req_id = GetRequestId(request);
  InitRequestStatesIfNew(req_id);
  event_order_[req_id] += "OnBeforeRetry\n";
  EXPECT_TRUE(next_states_[req_id] & kStageBeforeRetry) << event_order_[req_id];
  next_states_[req_id] = kStageBeforeURLRequest;
}

void TestNetworkDelegate::OnResponseStarted(URLRequest* request,
                                            int net_error) {
  DCHECK_NE(ERR_IO_PENDING, net_error);

  LoadTimingInfo load_timing_info;
  request->GetLoadTimingInfo(&load_timing_info);
  EXPECT_FALSE(load_timing_info.request_start_time.is_null());
  EXPECT_FALSE(load_timing_info.request_start.is_null());

  int req_id = GetRequestId(request);
  InitRequestStatesIfNew(req_id);
  event_order_[req_id] += "OnResponseStarted\n";
  EXPECT_TRUE(next_states_[req_id] & kStageResponseStarted)
      << event_order_[req_id];
  next_states_[req_id] = kStageCompletedSuccess | kStageCompletedError;
  if (net_error == ERR_ABORTED)
    return;

  if (net_error != OK) {
    error_count_++;
    last_error_ = net_error;
  }
}

void TestNetworkDelegate::OnCompleted(URLRequest* request,
                                      bool started,
                                      int net_error) {
  DCHECK_NE(net_error, net::ERR_IO_PENDING);

  int req_id = GetRequestId(request);
  InitRequestStatesIfNew(req_id);
  event_order_[req_id] += "OnCompleted\n";
  // Expect "Success -> (next_states_ & kStageCompletedSuccess)"
  // is logically identical to
  // Expect "!(Success) || (next_states_ & kStageCompletedSuccess)"
  EXPECT_TRUE(net_error != OK ||
              (next_states_[req_id] & kStageCompletedSuccess))
      << event_order_[req_id];
  EXPECT_TRUE(net_error == OK || (next_states_[req_id] & kStageCompletedError))
      << event_order_[req_id];
  next_states_[req_id] = kStageURLRequestDestroyed;
  completed_requests_++;
  if (net_error == ERR_ABORTED) {
    canceled_requests_++;
  } else if (net_error != OK) {
    error_count_++;
    last_error_ = net_error;
  } else {
    DCHECK_EQ(OK, net_error);
  }
}

void TestNetworkDelegate::OnURLRequestDestroyed(URLRequest* request) {
  int req_id = GetRequestId(request);
  InitRequestStatesIfNew(req_id);
  event_order_[req_id] += "OnURLRequestDestroyed\n";
  EXPECT_TRUE(next_states_[req_id] & kStageURLRequestDestroyed) <<
      event_order_[req_id];
  next_states_[req_id] = kStageDestruction;
  destroyed_requests_++;
}

bool TestNetworkDelegate::OnAnnotateAndMoveUserBlockedCookies(
    const URLRequest& request,
    const net::FirstPartySetMetadata& first_party_set_metadata,
    net::CookieAccessResultList& maybe_included_cookies,
    net::CookieAccessResultList& excluded_cookies) {
  RecordCookieSettingOverrides(request.cookie_setting_overrides());
  bool allow = true;
  if (cookie_options_bit_mask_ & NO_GET_COOKIES)
    allow = false;

  if (!allow) {
    blocked_annotate_cookies_count_++;
    ExcludeAllCookies(CookieInclusionStatus::EXCLUDE_USER_PREFERENCES,
                      maybe_included_cookies, excluded_cookies);
  }

  return allow;
}

NetworkDelegate::PrivacySetting TestNetworkDelegate::OnForcePrivacyMode(
    const URLRequest& request) const {
  RecordCookieSettingOverrides(request.cookie_setting_overrides());
  return NetworkDelegate::PrivacySetting::kStateAllowed;
}

bool TestNetworkDelegate::OnCanSetCookie(
    const URLRequest& request,
    const net::CanonicalCookie& cookie,
    CookieOptions* options,
    const net::FirstPartySetMetadata& first_party_set_metadata,
    CookieInclusionStatus* inclusion_status) {
  RecordCookieSettingOverrides(request.cookie_setting_overrides());
  bool allow = true;
  if (cookie_options_bit_mask_ & NO_SET_COOKIE)
    allow = false;

  if (!allow) {
    blocked_set_cookie_count_++;
  } else {
    set_cookie_count_++;
  }

  return allow;
}

bool TestNetworkDelegate::OnCancelURLRequestWithPolicyViolatingReferrerHeader(
    const URLRequest& request,
    const GURL& target_url,
    const GURL& referrer_url) const {
  return cancel_request_with_policy_violating_referrer_;
}

int TestNetworkDelegate::GetRequestId(URLRequest* request) {
  TestRequestId* test_request_id = reinterpret_cast<TestRequestId*>(
      request->GetUserData(kTestNetworkDelegateRequestIdKey));
  if (test_request_id)
    return test_request_id->id();
  int id = next_request_id_++;
  request->SetUserData(kTestNetworkDelegateRequestIdKey,
                       std::make_unique<TestRequestId>(id));
  return id;
}

std::optional<cookie_util::StorageAccessStatus>
TestNetworkDelegate::OnGetStorageAccessStatus(
    const URLRequest& request,
    base::optional_ref<const RedirectInfo> redirect_info) const {
  return storage_access_status_;
}

bool TestNetworkDelegate::OnIsStorageAccessHeaderEnabled(
    const url::Origin* top_frame_origin,
    const GURL& url) const {
  return is_storage_access_header_enabled_;
}

FilteringTestNetworkDelegate::FilteringTestNetworkDelegate() = default;
FilteringTestNetworkDelegate::~FilteringTestNetworkDelegate() = default;

bool FilteringTestNetworkDelegate::OnCanSetCookie(
    const URLRequest& request,
    const net::CanonicalCookie& cookie,
    CookieOptions* options,
    const net::FirstPartySetMetadata& first_party_set_metadata,
    CookieInclusionStatus* inclusion_status) {
  // Filter out cookies with the same name as |cookie_name_filter_| and
  // combine with |allowed_from_caller|.
  bool allowed = cookie.Name() != cookie_name_filter_;

  ++set_cookie_called_count_;

  if (!allowed)
    ++blocked_set_cookie_count_;

  // Call the nested delegate's method first to avoid a short circuit.
  return TestNetworkDelegate::OnCanSetCookie(request, cookie, options,
                                             first_party_set_metadata,
                                             inclusion_status) &&
         allowed;
}

NetworkDelegate::PrivacySetting
FilteringTestNetworkDelegate::OnForcePrivacyMode(
    const URLRequest& request) const {
  if (force_privacy_mode_) {
    return partitioned_state_allowed_
               ? NetworkDelegate::PrivacySetting::kPartitionedStateAllowedOnly
               : NetworkDelegate::PrivacySetting::kStateDisallowed;
  }

  return TestNetworkDelegate::OnForcePrivacyMode(request);
}

bool FilteringTestNetworkDelegate::OnAnnotateAndMoveUserBlockedCookies(
    const URLRequest& request,
    const net::FirstPartySetMetadata& first_party_set_metadata,
    net::CookieAccessResultList& maybe_included_cookies,
    net::CookieAccessResultList& excluded_cookies) {
  // Filter out cookies if |block_annotate_cookies_| is set and
  // combine with |allowed_from_caller|.
  bool allowed = !block_annotate_cookies_;

  ++annotate_cookies_called_count_;

  if (!allowed) {
    ++blocked_annotate_cookies_count_;
    ExcludeAllCookies(net::CookieInclusionStatus::EXCLUDE_USER_PREFERENCES,
                      maybe_included_cookies, excluded_cookies);
  }

  if (allowed && block_get_cookies_by_name_ && !cookie_name_filter_.empty()) {
    for (auto& cookie : maybe_included_cookies) {
      if (cookie.cookie.Name().find(cookie_name_filter_) != std::string::npos) {
        cookie.access_result.status.AddExclusionReason(
            net::CookieInclusionStatus::EXCLUDE_USER_PREFERENCES);
      }
    }
    for (auto& cookie : excluded_cookies) {
      if (cookie.cookie.Name().find(cookie_name_filter_) != std::string::npos) {
        cookie.access_result.status.AddExclusionReason(
            net::CookieInclusionStatus::EXCLUDE_USER_PREFERENCES);
      }
    }

    MoveExcludedCookies(maybe_included_cookies, excluded_cookies);
  }

  // Call the nested delegate's method first to avoid a short circuit.
  return TestNetworkDelegate::OnAnnotateAndMoveUserBlockedCookies(
             request, first_party_set_metadata, maybe_included_cookies,
             excluded_cookies) &&
         allowed;
}

// URLRequestInterceptor that intercepts only the first request it sees,
// returning the provided URLRequestJob.
class TestScopedURLInterceptor::TestRequestInterceptor
    : public URLRequestInterceptor {
 public:
  explicit TestRequestInterceptor(std::unique_ptr<URLRequestJob> intercept_job)
      : intercept_job_(std::move(intercept_job)) {}

  ~TestRequestInterceptor() override { CHECK(safe_to_delete_); }

  std::unique_ptr<URLRequestJob> MaybeInterceptRequest(
      URLRequest* request) const override {
    return std::move(intercept_job_);
  }

  bool job_used() const { return intercept_job_.get() == nullptr; }
  void set_safe_to_delete() { safe_to_delete_ = true; }

 private:
  mutable std::unique_ptr<URLRequestJob> intercept_job_;
  // This is used to catch chases where the TestRequestInterceptor is destroyed
  // before the TestScopedURLInterceptor.
  bool safe_to_delete_ = false;
};

TestScopedURLInterceptor::TestScopedURLInterceptor(
    const GURL& url,
    std::unique_ptr<URLRequestJob> intercept_job)
    : url_(url) {
  std::unique_ptr<TestRequestInterceptor> interceptor =
      std::make_unique<TestRequestInterceptor>(std::move(intercept_job));
  interceptor_ = interceptor.get();
  URLRequestFilter::GetInstance()->AddUrlInterceptor(url_,
                                                     std::move(interceptor));
}

TestScopedURLInterceptor::~TestScopedURLInterceptor() {
  DCHECK(interceptor_->job_used());
  interceptor_->set_safe_to_delete();
  interceptor_ = nullptr;
  URLRequestFilter::GetInstance()->RemoveUrlHandler(url_);
}

}  // namespace net