/*
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#pragma once

#include <folly/experimental/coro/BlockingWait.h>
#include <folly/experimental/coro/Task.h>
#include <folly/portability/GTest.h>

/**
 * This is based on the GTEST_TEST_ macro from gtest-internal.h. It seems that
 * gtest doesn't yet support coro tests, so this macro adds a way to define a
 * test case written as a coroutine using folly::coro::Task. It will be called
 * using folly::coro::blockingWait().
 *
 * Note that you cannot use ASSERT macros in coro tests. See below for
 * CO_ASSERT_*.
 */
// clang-format off
#define CO_TEST_(test_case_name, test_name, parent_class, parent_id)\
class GTEST_TEST_CLASS_NAME_(test_case_name, test_name) : public parent_class {\
 public:\
  GTEST_TEST_CLASS_NAME_(test_case_name, test_name)() {}\
 private:\
  void TestBody() override;\
  folly::coro::Task<void> co_TestBody();\
  static ::testing::TestInfo* const test_info_ GTEST_ATTRIBUTE_UNUSED_;\
  GTEST_DISALLOW_COPY_AND_ASSIGN_(\
      GTEST_TEST_CLASS_NAME_(test_case_name, test_name));\
};\
\
::testing::TestInfo* const GTEST_TEST_CLASS_NAME_(test_case_name, test_name)\
  ::test_info_ = /* NOLINT */ \
    ::testing::internal::MakeAndRegisterTestInfo(\
        GTEST_STRINGIFY_TOKEN_(test_case_name), \
        GTEST_STRINGIFY_TOKEN_(test_name), NULL, NULL, \
        ::testing::internal::CodeLocation(__FILE__, __LINE__), /* NOLINT */ \
        (parent_id), \
        parent_class::SetUpTestCase, \
        parent_class::TearDownTestCase, \
        new ::testing::internal::TestFactoryImpl< /* NOLINT */ \
            GTEST_TEST_CLASS_NAME_(test_case_name, test_name)>);\
void GTEST_TEST_CLASS_NAME_(test_case_name, test_name)::TestBody() {\
  folly::coro::blockingWait(co_TestBody());\
}\
folly::coro::Task<void> GTEST_TEST_CLASS_NAME_(test_case_name, test_name)::co_TestBody()
// clang-format on

/**
 * TEST() for coro tests.
 */
#define CO_TEST(test_case_name, test_name) \
  CO_TEST_(                                \
      test_case_name,                      \
      test_name,                           \
      ::testing::Test,                     \
      ::testing::internal::GetTestTypeId())

/**
 * TEST_F() for coro tests.
 */
#define CO_TEST_F(test_fixture, test_name) \
  CO_TEST_(                                \
      test_fixture,                        \
      test_name,                           \
      test_fixture,                        \
      ::testing::internal::GetTypeId<test_fixture>())

/**
 * Coroutine versions of GTests's Assertion predicate macros. Use these in place
 * of ASSERT_* in CO_TEST or coroutine functions.
 */
#define CO_GTEST_FATAL_FAILURE_(message) \
  co_return GTEST_MESSAGE_(message, ::testing::TestPartResult::kFatalFailure)
#define CO_ASSERT_PRED_FORMAT2(pred_format, v1, v2) \
  GTEST_PRED_FORMAT2_(pred_format, v1, v2, CO_GTEST_FATAL_FAILURE_)

#define CO_ASSERT_TRUE(condition) \
  GTEST_TEST_BOOLEAN_(            \
      (condition), #condition, false, true, CO_GTEST_FATAL_FAILURE_)
#define CO_ASSERT_FALSE(condition) \
  GTEST_TEST_BOOLEAN_(             \
      !(condition), #condition, true, false, CO_GTEST_FATAL_FAILURE_)
#define CO_ASSERT_EQ(val1, val2)                                            \
  ASSERT_PRED_FORMAT2(                                                      \
      ::testing::internal::EqHelper<GTEST_IS_NULL_LITERAL_(val1)>::Compare, \
      val1,                                                                 \
      val2)
#define CO_ASSERT_NE(val1, val2) \
  CO_ASSERT_PRED_FORMAT2(::testing::internal::CmpHelperNE, val1, val2)
#define CO_ASSERT_LE(val1, val2) \
  CO_ASSERT_PRED_FORMAT2(::testing::internal::CmpHelperLE, val1, val2)
#define CO_ASSERT_LT(val1, val2) \
  CO_ASSERT_PRED_FORMAT2(::testing::internal::CmpHelperLT, val1, val2)
#define CO_ASSERT_GE(val1, val2) \
  CO_ASSERT_PRED_FORMAT2(::testing::internal::CmpHelperGE, val1, val2)
#define CO_ASSERT_GT(val1, val2) \
  CO_ASSERT_PRED_FORMAT2(::testing::internal::CmpHelperGT, val1, val2)
