AnyTests.cpp

#include <catch2/catch.hpp>

#include "rapidcheck/detail/Any.h"

#include "util/Util.h"
#include "util/Predictable.h"

using namespace rc;
using namespace rc::detail;

namespace {

enum class InitType { Value, Move, Copy, Dead };

std::ostream &operator<<(std::ostream &os, InitType itype) {
  switch (itype) {
  case InitType::Value:
    os << "Value";
    break;
  case InitType::Move:
    os << "Moved";
    break;
  case InitType::Copy:
    os << "Copied";
    break;
  case InitType::Dead:
    os << "Dead";
    break;
  }

  return os;
}

template <typename T>
struct InitTracker {
  InitType itype;
  T value;

  InitTracker(T v)
      : itype(InitType::Value)
      , value(v) {}
  InitTracker(const InitTracker<T> &other)
      : itype(InitType::Copy)
      , value(other.value) {}
  InitTracker(InitTracker<T> &&other)
      : itype(InitType::Move)
      , value(std::move(other.value)) {
    other.itype = InitType::Dead;
  }
};

template <typename T>
void show(const InitTracker<T> &value, std::ostream &os) {
  os << "[" << value.itype << "]";
  if (value.itype != InitType::Dead) {
    os << ": ";
    rc::show(value.value, os);
  }
}

using StringTracker = InitTracker<std::string>;

} // namespace

TEST_CASE("Any") {
  StringTracker x("foobar");
  REQUIRE(x.itype == InitType::Value);

  SECTION("of") {
    SECTION("allows move") {
      Any any = Any::of(std::move(x));
      auto &valueRef = any.get<StringTracker>();
      REQUIRE(valueRef.itype == InitType::Move);
    }

    SECTION("allows copy") {
      Any any = Any::of(x);
      auto &valueRef = any.get<StringTracker>();
      REQUIRE(valueRef.itype == InitType::Copy);
    }
  }

  SECTION("reset") {
    SECTION("turns this into null any") {
      Any any = Any::of("foobar");
      any.reset();
      REQUIRE(!any);
    }
  }

  SECTION("get") {
    SECTION("returns a reference to the value") {
      Any anystr = Any::of(std::string("foobar"));
      REQUIRE(anystr.get<std::string>() == "foobar");
      anystr.get<std::string>()[0] = 'b';
      REQUIRE(anystr.get<std::string>() == "boobar");

      Any anyint = Any::of(static_cast<int>(100));
      REQUIRE(anyint.get<int>() == 100);
      anyint.get<int>()++;
      REQUIRE(anyint.get<int>() == 101);
    }

    SECTION("works as a move source") {
      std::string str("foobar");
      Any any = Any::of(str);
      std::string dest(std::move(any.get<std::string>()));
      REQUIRE(str == dest);
    }
  }

  SECTION("showType") {
    SECTION("returns a pair of the typename and value as strings") {
      std::string str("foobar");
      Any any = Any::of(str);

      std::ostringstream ss;
      any.showType(ss);

      REQUIRE(ss.str() == typeToString<decltype(str)>());
    }

    SECTION("outputs nothing for null Any values") {
      Any any;
      std::ostringstream ss;
      any.showType(ss);
      REQUIRE(ss.str().empty());
    }
  }

  SECTION("showValue") {
    SECTION("returns a pair of the typename and value as strings") {
      std::string str("foobar");
      Any any = Any::of(str);

      std::ostringstream ss;
      any.showValue(ss);

      REQUIRE(ss.str() == toString(str));
    }

    SECTION("outputs nothing for null Any values") {
      Any any;
      std::ostringstream ss;
      any.showValue(ss);
      REQUIRE(ss.str().empty());
    }
  }

  SECTION("operator bool()") {
    SECTION("returns false for null Any") {
      Any any;
      REQUIRE(!any);
    }

    SECTION("returns true for non-null Any") {
      Any any = Any::of(1337);
      REQUIRE(any);
    }
  }

  SECTION("move constructor") {
    SECTION("if not null") {
      std::string str("foobar");
      Any from = Any::of(str);
      auto addr = &from.get<std::string>();
      Any to(std::move(from));

      SECTION("value is equal to original") {
        REQUIRE(to.get<std::string>() == str);
      }
      SECTION("original is reset") { REQUIRE(!from); }
      SECTION("addr is the same as original") {
        REQUIRE(&to.get<std::string>() == addr);
      }
    }

    SECTION("if from is null, to is also null") {
      Any from;
      Any to(std::move(from));
      REQUIRE(!to);
    }
  }

  SECTION("move assignment operator") {
    SECTION("if not null") {
      std::string str("foobar");
      Any from = Any::of(str);
      auto addr = &from.get<std::string>();
      Any to;
      to = std::move(from);

      SECTION("value is equal to original") {
        REQUIRE(to.get<std::string>() == str);
      }
      SECTION("original is reset") { REQUIRE(!from); }
      SECTION("addr is the same as original") {
        REQUIRE(&to.get<std::string>() == addr);
      }
    }

    SECTION("if from is null, to is also null") {
      Any from;
      Any to;
      to = std::move(from);
      REQUIRE(!to);
    }
  }
}