Machine-local policy files should not affect tests

chrome/test/base/testing_browser_process.cc

 // Copyright (c) 2012 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/test/base/testing_browser_process.h"
 
+#include "base/path_service.h"
 #include "base/strings/string_util.h"
 #include "base/time/default_clock.h"
 #include "base/time/default_tick_clock.h"
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_process_impl.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
 #include "chrome/browser/memory/tab_manager.h"
 #include "chrome/browser/notifications/notification_platform_bridge.h"
 #include "chrome/browser/notifications/notification_ui_manager.h"
 #include "chrome/browser/printing/print_job_manager.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/safe_browsing/safe_browsing_service.h"
+#include "chrome/common/chrome_paths.h"
 #include "chrome/common/features.h"
 #include "chrome/test/base/testing_browser_process_platform_part.h"
 #include "components/network_time/network_time_tracker.h"
 #include "components/policy/core/browser/browser_policy_connector.h"
 #include "components/prefs/pref_service.h"
 #include "components/subresource_filter/core/browser/ruleset_service.h"
 #include "content/public/browser/notification_service.h"
 #include "extensions/features/features.h"
 #include "media/media_features.h"
 #include "net/url_request/url_request_context_getter.h"
@@ skipping 114 matching lines @@
 
 variations::VariationsService* TestingBrowserProcess::variations_service() {
   return nullptr;
 }
 
 policy::BrowserPolicyConnector*
     TestingBrowserProcess::browser_policy_connector() {
   if (!browser_policy_connector_) {
     EXPECT_FALSE(created_browser_policy_connector_);
     created_browser_policy_connector_ = true;
+
+#if defined(OS_POSIX) && !defined(OS_MACOSX)
+    // Make sure that the machine policy directory does not exist so that
+    // machine-wide poilcies do not affect tests.

[Thiemo Nagel, 2017/01/10 13:24:37]

Nit: typo

[pmarko, 2017/01/11 09:09:25]

Done.

+    // If a test needs to place a file in this directory in the future, we could
+    // create a temporary directory and make its path available to tests.
+    base::FilePath local_policy_path("/tmp/non/existing/directory");

[Paweł Hajdan Jr., 2017/01/05 15:48:02]

Why is this in POSIX non-OSX #ifdef?

[pmarko, 2017/01/05 16:07:53]

See Reply on test_launcher_util.cc - if we decide to add the information to the
comment, I'd of course add it here too.

+    EXPECT_TRUE(PathService::OverrideAndCreateIfNeeded(
+        chrome::DIR_POLICY_FILES, local_policy_path, true, false));
+#endif
+
     browser_policy_connector_ = platform_part_->CreateBrowserPolicyConnector();
 
     // Note: creating the ChromeBrowserPolicyConnector invokes BrowserThread::
     // GetTaskRunnerForThread(), which initializes a base::LazyInstance of
     // BrowserThreadTaskRunners. However, the threads that these task runners
     // would run tasks on are *also* created lazily and might not exist yet.
     // Creating them requires a MessageLoop, which a test can optionally create
     // and manage itself, so don't do it here.
   }
   return browser_policy_connector_.get();
@@ skipping 292 matching lines @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
 TestingBrowserProcessInitializer::TestingBrowserProcessInitializer() {
   TestingBrowserProcess::CreateInstance();
 }
 
 TestingBrowserProcessInitializer::~TestingBrowserProcessInitializer() {
   TestingBrowserProcess::DeleteInstance();
 }