etl/test/test_overload.cpp

/******************************************************************************
The MIT License(MIT)

Embedded Template Library.
https://github.com/ETLCPP/etl
https://www.etlcpp.com

Copyright(c) 2015 jwellbelove

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files(the "Software"), to deal
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
******************************************************************************/

#include "unit_test_framework.h"

#include "etl/overload.h"

#include <iostream>

namespace
{
  struct Result
  {
    Result()
      : bi(false)
      , bd(false)
      , bs(false)
    {
    }

    void clear()
    {
      bi = false;
      bd = false;
      bs = false;
    }

    bool bi;
    bool bd;
    bool bs;
  };

  Result result;

  struct Visitor
  {
    void operator ()(int i) { result.bi = true; }
    void operator ()(double d) { result.bd = true; }
    void operator ()(const std::string& s) { result.bs = true; }
  };

  template <typename T, typename TOverload>
  void Function(T value, TOverload&& ol)
  {
    ol(value);
  }

  SUITE(test_overload)
  {
    //*************************************************************************
    TEST(test_overload_lambdas)
    {
      auto overload = etl::make_overload([](int i) { result.bi = true; },
                                         [](double d) { result.bd = true; },
                                         [](const std::string& s) { result.bs = true; });

      result.clear();
      Function(int(1), overload);
      CHECK(result.bi == true);
      CHECK(result.bd == false);
      CHECK(result.bs == false);

      result.clear();
      Function(double(2.0), overload);
      CHECK(result.bi == false);
      CHECK(result.bd == true);
      CHECK(result.bs == false);

      result.clear();
      Function(std::string("3"), overload);
      CHECK(result.bi == false);
      CHECK(result.bd == false);
      CHECK(result.bs == true);
    }

    //*************************************************************************
    TEST(test_overload_lambdas_cpp17)
    {
#if !defined(ETL_OVERLOAD_FORCE_CPP14)
      result.clear();
      Function(int(1), etl::overload
                       {
                         [](int i) { result.bi = true; },
                         [](double d) { result.bd = true; },
                         [](const std::string& s) { result.bs = true; }
                       });
      CHECK(result.bi == true);
      CHECK(result.bd == false);
      CHECK(result.bs == false);

      result.clear();
      Function(double(2.0), etl::overload
                            {
                              [](int i) { result.bi = true; },
                              [](double d) { result.bd = true; },
                              [](const std::string& s) { result.bs = true; }
                            });
      CHECK(result.bi == false);
      CHECK(result.bd == true);
      CHECK(result.bs == false);

      result.clear();
      Function(std::string("3"), etl::overload
                                 {
                                   [](int i) { result.bi = true; },
                                   [](double d) { result.bd = true; },
                                   [](const std::string& s) { result.bs = true; }
                                 });
      CHECK(result.bi == false);
      CHECK(result.bd == false);
      CHECK(result.bs == true);
#endif
    }

    //*************************************************************************
    TEST(test_visitor_overload)
    {
      auto overload = etl::make_overload(Visitor());

      result.clear();
      Function(int(1), overload);
      CHECK(result.bi == true);
      CHECK(result.bd == false);
      CHECK(result.bs == false);

      result.clear();
      Function(double(2.0), overload);
      CHECK(result.bi == false);
      CHECK(result.bd == true);
      CHECK(result.bs == false);

      result.clear();
      Function(std::string("3"), overload);
      CHECK(result.bi == false);
      CHECK(result.bd == false);
      CHECK(result.bs == true);
    }
  };
}