Extract functionality of test_main into separate library.

Extract functionality of test_main into separate library to be able to
reuse it if another main will be required.

Bug: webrtc:5996
Change-Id: I2925b4240bd0e4fb884b43bb16667ca2d6216bbd
Reviewed-on: https://webrtc-review.googlesource.com/c/105921
Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Artem Titov <titovartem@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25172}

test/test_main_lib.cc

@@ -0,0 +1,168 @@
+/*
+ *  Copyright (c) 2018 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "test/test_main_lib.h"
+
+#include <fstream>
+#include <string>
+
+#include "rtc_base/flags.h"
+#include "rtc_base/logging.h"
+#include "rtc_base/thread.h"
+#include "system_wrappers/include/field_trial.h"
+#include "system_wrappers/include/metrics.h"
+#include "test/field_trial.h"
+#include "test/gmock.h"
+#include "test/gtest.h"
+#include "test/testsupport/fileutils.h"
+#include "test/testsupport/perf_test.h"
+
+#if defined(WEBRTC_WIN)
+#include "rtc_base/win32socketinit.h"
+#endif
+
+#if defined(WEBRTC_IOS)
+#include "test/ios/test_support.h"
+
+DEFINE_string(NSTreatUnknownArgumentsAsOpen,
+              "",
+              "Intentionally ignored flag intended for iOS simulator.");
+DEFINE_string(ApplePersistenceIgnoreState,
+              "",
+              "Intentionally ignored flag intended for iOS simulator.");
+DEFINE_bool(
+    save_chartjson_result,
+    false,
+    "Store the perf results in Documents/perf_result.json in the format "
+    "described by "
+    "https://github.com/catapult-project/catapult/blob/master/dashboard/docs/"
+    "data-format.md.");
+
+#else
+
+DEFINE_string(
+    isolated_script_test_output,
+    "",
+    "Path to output an empty JSON file which Chromium infra requires.");
+
+DEFINE_string(
+    isolated_script_test_perf_output,
+    "",
+    "Path where the perf results should be stored in the JSON format described "
+    "by "
+    "https://github.com/catapult-project/catapult/blob/master/dashboard/docs/"
+    "data-format.md.");
+
+#endif
+
+DEFINE_bool(logs, false, "print logs to stderr");
+
+DEFINE_string(
+    force_fieldtrials,
+    "",
+    "Field trials control experimental feature code which can be forced. "
+    "E.g. running with --force_fieldtrials=WebRTC-FooFeature/Enable/"
+    " will assign the group Enable to field trial WebRTC-FooFeature.");
+
+DEFINE_bool(help, false, "Print this message.");
+
+namespace webrtc {
+
+namespace {
+
+class TestMainImpl : public TestMain {
+ public:
+  int Init(int argc, char* argv[]) override {
+    ::testing::InitGoogleMock(&argc, argv);
+
+    // Default to LS_INFO, even for release builds to provide better test
+    // logging.
+    // TODO(pbos): Consider adding a command-line override.
+    if (rtc::LogMessage::GetLogToDebug() > rtc::LS_INFO)
+      rtc::LogMessage::LogToDebug(rtc::LS_INFO);
+
+    if (rtc::FlagList::SetFlagsFromCommandLine(&argc, argv, false)) {
+      return 1;
+    }
+    if (FLAG_help) {
+      rtc::FlagList::Print(nullptr, false);
+      return 0;
+    }
+
+    // TODO(bugs.webrtc.org/9792): we need to reference something from
+    // fileutils.h so that our downstream hack where we replace fileutils.cc
+    // works. Otherwise the downstream flag implementation will take over and
+    // botch the flag introduced by the hack. Remove this awful thing once the
+    // downstream implementation has been eliminated.
+    (void)webrtc::test::JoinFilename("horrible", "hack");
+
+    webrtc::test::ValidateFieldTrialsStringOrDie(FLAG_force_fieldtrials);
+    // InitFieldTrialsFromString stores the char*, so the char array must
+    // outlive the application.
+    webrtc::field_trial::InitFieldTrialsFromString(FLAG_force_fieldtrials);
+    webrtc::metrics::Enable();
+
+#if defined(WEBRTC_WIN)
+    winsock_init_ = absl::make_unique<rtc::WinsockInitializer>();
+#endif
+
+    rtc::LogMessage::SetLogToStderr(FLAG_logs);
+
+    // Ensure that main thread gets wrapped as an rtc::Thread.
+    // TODO(bugs.webrt.org/9714): It might be better to avoid wrapping the main
+    // thread, or leave it to individual tests that need it. But as long as we
+    // have automatic thread wrapping, we need this to avoid that some other
+    // random thread (which one depending on which tests are run) gets
+    // automatically wrapped.
+    rtc::ThreadManager::Instance()->WrapCurrentThread();
+    RTC_CHECK(rtc::Thread::Current());
+    return 0;
+  }
+
+  int Run(int argc, char* argv[]) override {
+#if defined(WEBRTC_IOS)
+    rtc::test::InitTestSuite(RUN_ALL_TESTS, argc, argv,
+                             FLAG_save_chartjson_result);
+    rtc::test::RunTestsFromIOSApp();
+    return 0;
+#else
+    int exit_code = RUN_ALL_TESTS();
+
+    std::string chartjson_result_file = FLAG_isolated_script_test_perf_output;
+    if (!chartjson_result_file.empty()) {
+      webrtc::test::WritePerfResults(chartjson_result_file);
+    }
+
+    std::string result_filename = FLAG_isolated_script_test_output;
+    if (!result_filename.empty()) {
+      std::ofstream result_file(result_filename);
+      result_file << "{\"version\": 3}";
+      result_file.close();
+    }
+
+    return exit_code;
+#endif
+  }
+
+  ~TestMainImpl() override = default;
+
+ private:
+#if defined(WEBRTC_WIN)
+  std::unique_ptr<rtc::WinsockInitializer> winsock_init_;
+#endif
+};
+
+}  // namespace
+
+std::unique_ptr<TestMain> TestMain::Create() {
+  return absl::make_unique<TestMainImpl>();
+}
+
+}  // namespace webrtc