/* Unit testing for outcomes
(C) 2013-2019 Niall Douglas <http://www.nedproductions.biz/> (18 commits)


Boost Software License - Version 1.0 - August 17th, 2003

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*/

#include <boost/outcome/outcome.hpp>
#include <boost/test/unit_test.hpp>
#include <boost/test/unit_test_monitor.hpp>

#include <iostream>

#ifdef _MSC_VER
#pragma warning(disable : 4702)  // unreachable code
#endif

BOOST_OUTCOME_AUTO_TEST_CASE(works_outcome, "Tests that the outcome works as intended")
{
  using namespace BOOST_OUTCOME_V2_NAMESPACE;

  static_assert(std::is_constructible<outcome<long>, int>::value, "Sanity check that monad can be constructed from a value_type");
  static_assert(!std::is_constructible<outcome<outcome<long>>, int>::value, "Sanity check that outer monad can be constructed from an inner monad's value_type");
  static_assert(!std::is_constructible<outcome<outcome<outcome<long>>>, int>::value, "Sanity check that outer monad can be constructed from an inner inner monad's value_type");
  static_assert(!std::is_constructible<outcome<outcome<outcome<outcome<long>>>>, int>::value, "Sanity check that outer monad can be constructed from an inner inner monad's value_type");

  static_assert(std::is_constructible<outcome<int>, outcome<long>>::value, "Sanity check that compatible monads can be constructed from one another");
  static_assert(std::is_constructible<outcome<outcome<int>>, outcome<long>>::value, "Sanity check that outer monad can be constructed from a compatible monad");
  static_assert(!std::is_constructible<outcome<outcome<outcome<int>>>, outcome<long>>::value, "Sanity check that outer monad can be constructed from a compatible monad up to two nestings deep");
  static_assert(!std::is_constructible<outcome<outcome<outcome<outcome<int>>>>, outcome<long>>::value, "Sanity check that outer monad can be constructed from a compatible monad three or more nestings deep");
  static_assert(!std::is_constructible<outcome<std::string>, outcome<int>>::value, "Sanity check that incompatible monads cannot be constructed from one another");

  static_assert(std::is_constructible<outcome<int>, outcome<void>>::value, "Sanity check that all monads can be constructed from a void monad");
  static_assert(std::is_constructible<outcome<outcome<int>>, outcome<void>>::value, "Sanity check that outer monad can be constructed from a compatible monad");
  static_assert(std::is_constructible<outcome<outcome<outcome<int>>>, outcome<void>>::value, "Sanity check that outer monad can be constructed from a compatible monad up to two nestings deep");
  static_assert(!std::is_constructible<outcome<void>, outcome<int>>::value, "Sanity check that incompatible monads cannot be constructed from one another");

  static_assert(std::is_void<result<void>::value_type>::value, "Sanity check that result<void> has a void value_type");
  static_assert(std::is_void<result<void, void>::error_type>::value, "Sanity check that result<void, void> has a void error_type");
  // static_assert(std::is_void<outcome<void, void, void>::exception_type>::value, "Sanity check that outcome<void, void, void> has a void exception_type");

  static_assert(std::is_same<outcome<int>::value_type, int>::value, "Sanity check that outcome<int> has a int value_type");
  static_assert(std::is_same<outcome<int>::error_type, boost::system::error_code>::value, "Sanity check that outcome<int> has a error_code error_type");
  static_assert(std::is_same<outcome<int>::exception_type, boost::exception_ptr>::value, "Sanity check that outcome<int> has a exception_ptr exception_type");


  {  // errored int
    outcome<int> m(boost::system::errc::bad_address);
    BOOST_CHECK(!m);
    BOOST_CHECK(!m.has_value());
    BOOST_CHECK(m.has_error());
    BOOST_CHECK(!m.has_exception());
    BOOST_CHECK_THROW(m.value(), boost::system::system_error);
    BOOST_CHECK_NO_THROW(m.error());
    BOOST_CHECK_THROW(m.exception(), bad_outcome_access);
    BOOST_CHECK_THROW(boost::rethrow_exception(m.failure()), boost::system::system_error);
  }
  {  // errored void
    outcome<void> m(boost::system::errc::bad_address);
    BOOST_CHECK(!m);
    BOOST_CHECK(!m.has_value());
    BOOST_CHECK(m.has_error());
    BOOST_CHECK(!m.has_exception());
    BOOST_CHECK_THROW(([&m]() -> void { return m.value(); }()), boost::system::system_error);
    BOOST_CHECK_NO_THROW(m.error());
    BOOST_CHECK_THROW(m.exception(), bad_outcome_access);
    BOOST_CHECK_THROW(boost::rethrow_exception(m.failure()), boost::system::system_error);
  }
  {  // valued int
    outcome<int> m(5);
    BOOST_CHECK(m);
    BOOST_CHECK(m.has_value());
    BOOST_CHECK(!m.has_error());
    BOOST_CHECK(!m.has_exception());
    BOOST_CHECK(m.value() == 5);
    m.value() = 6;
    BOOST_CHECK(m.value() == 6);
    BOOST_CHECK_THROW(m.error(), bad_outcome_access);
    BOOST_CHECK_THROW(m.exception(), bad_outcome_access);
    BOOST_CHECK(!m.failure());
  }
  {  // moves do not clear state
    outcome<std::string> m("niall");
    BOOST_CHECK(m);
    BOOST_CHECK(m.has_value());
    BOOST_CHECK(!m.has_error());
    BOOST_CHECK(!m.has_exception());
    BOOST_CHECK(m.value() == "niall");
    m.value() = "NIALL";
    BOOST_CHECK(m.value() == "NIALL");
    auto temp(std::move(m).value());
    BOOST_CHECK(temp == "NIALL");
    BOOST_CHECK(m.value().empty());  // NOLINT
  }
  {  // valued void
    outcome<void> m(in_place_type<void>);
    BOOST_CHECK(m);
    BOOST_CHECK(m.has_value());
    BOOST_CHECK(!m.has_error());
    BOOST_CHECK(!m.has_exception());
    BOOST_CHECK_NO_THROW(m.value());  // works, but type returned is unusable
    BOOST_CHECK_THROW(m.error(), bad_outcome_access);
    BOOST_CHECK_THROW(m.exception(), bad_outcome_access);
    BOOST_CHECK(!m.failure());
  }
  {  // errored
    boost::system::error_code ec(5, boost::system::system_category());
    outcome<int> m(ec);
    BOOST_CHECK(!m);
    BOOST_CHECK(!m.has_value());
    BOOST_CHECK(m.has_error());
    BOOST_CHECK(!m.has_exception());
    BOOST_CHECK_THROW(m.value(), boost::system::system_error);
    BOOST_CHECK(m.error() == ec);
    BOOST_CHECK_THROW(m.exception(), bad_outcome_access);
#ifndef BOOST_NO_EXCEPTIONS
    BOOST_CHECK(m.failure());
    try
    {
      boost::rethrow_exception(m.failure());
    }
    catch(const boost::system::system_error &ex)
    {
      BOOST_CHECK(ex.code() == ec);
      BOOST_CHECK(ex.code().value() == 5);
    }
#endif
  }
#if !defined(__APPLE__) || defined(__cpp_exceptions)
  {  // excepted
    boost::system::error_code ec(5, boost::system::system_category());
    auto e = boost::copy_exception(boost::system::system_error(ec));  // NOLINT
    outcome<int> m(e);
    BOOST_CHECK(!m);
    BOOST_CHECK(!m.has_value());
    BOOST_CHECK(!m.has_error());
    BOOST_CHECK(m.has_exception());
    BOOST_CHECK_THROW(m.value(), boost::system::system_error);
    BOOST_CHECK_THROW(m.error(), bad_outcome_access);
    BOOST_CHECK(m.exception() == e);
#ifndef BOOST_NO_EXCEPTIONS
    BOOST_CHECK(m.failure());
    try
    {
      boost::rethrow_exception(m.failure());
    }
    catch(const boost::system::system_error &ex)
    {
      BOOST_CHECK(ex.code() == ec);
      BOOST_CHECK(ex.code().value() == 5);
    }
#endif
  }
  {  // custom error type
    struct Foo
    {
    };
    auto e = boost::copy_exception(Foo());
    outcome<int> m(e);
    BOOST_CHECK(!m);
    BOOST_CHECK(!m.has_value());
    BOOST_CHECK(!m.has_error());
    BOOST_CHECK(m.has_exception());
    BOOST_CHECK_THROW(m.value(), Foo);
    BOOST_CHECK_THROW(m.error(), bad_outcome_access);
    BOOST_CHECK(m.exception() == e);
  }
  {  // outcome<void, void> should work
    boost::system::error_code ec(5, boost::system::system_category());
    auto e = boost::copy_exception(boost::system::system_error(ec));
    outcome<void, void> m(e);
    BOOST_CHECK(!m);
    BOOST_CHECK(!m.has_value());
    BOOST_CHECK(!m.has_error());
    BOOST_CHECK(m.has_exception());
  }
#endif


  {
    outcome<int> a(5);
    outcome<int> b(make_error_code(boost::system::errc::invalid_argument));
    std::cout << sizeof(a) << std::endl;  // 40 bytes
    a.assume_value();
    b.assume_error();
#ifndef BOOST_NO_EXCEPTIONS
    try
    {
      b.value();
      std::cerr << "fail" << std::endl;
      std::terminate();
    }
    catch(const boost::system::system_error & /*unused*/)
    {
    }
#endif
    static_assert(!std::is_default_constructible<decltype(a)>::value, "");
    static_assert(!std::is_nothrow_default_constructible<decltype(a)>::value, "");
    static_assert(std::is_copy_constructible<decltype(a)>::value, "");
    static_assert(!std::is_trivially_copy_constructible<decltype(a)>::value, "");
    static_assert(std::is_nothrow_copy_constructible<decltype(a)>::value, "");
    static_assert(std::is_copy_assignable<decltype(a)>::value, "");
    static_assert(!std::is_trivially_copy_assignable<decltype(a)>::value, "");
    static_assert(std::is_nothrow_copy_assignable<decltype(a)>::value, "");
    static_assert(!std::is_trivially_destructible<decltype(a)>::value, "");
    static_assert(std::is_nothrow_destructible<decltype(a)>::value, "");

    // Test void compiles
    outcome<void> c(in_place_type<void>);
    outcome<void> c2(c);
    (void) c2;
    // Test int, void compiles
    outcome<int, void> d(in_place_type<boost::exception_ptr>);
  }

  {
    // Can only be constructed via multiple args
    struct udt3
    {
      udt3() = delete;
      udt3(udt3 &&) = delete;
      udt3(const udt3 &) = delete;
      udt3 &operator=(udt3 &&) = delete;
      udt3 &operator=(const udt3 &) = delete;
      explicit udt3(int /*unused*/, const char * /*unused*/, std::nullptr_t /*unused*/) {}
      ~udt3() = default;
    };
    // Test a udt which can only be constructed in place compiles
    outcome<udt3> g(in_place_type<udt3>, 5, static_cast<const char *>("niall"), nullptr);
    // Does converting inplace construction also work?
    outcome<udt3> h(5, static_cast<const char *>("niall"), nullptr);
    outcome<udt3> i(ENOMEM, boost::system::generic_category());
    BOOST_CHECK(h.has_value());
    BOOST_CHECK(i.has_error());
  }
}