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#include <c10/test/util/Macros.h>
#include <c10/util/Metaprogramming.h>
#include <gtest/gtest.h>
#include <cstdlib>
using namespace c10::guts;
// NOLINTBEGIN(modernize*, cppcoreguidelines-special-member-functions)
namespace {
namespace test_function_traits {
static_assert(
std::is_same<
void,
typename function_traits<void(int, float)>::return_type>::value,
"");
static_assert(
std::is_same<int, typename function_traits<int(int, float)>::return_type>::
value,
"");
static_assert(
std::is_same<
typelist::typelist<int, float>,
typename function_traits<void(int, float)>::parameter_types>::value,
"");
static_assert(
std::is_same<
typelist::typelist<int, float>,
typename function_traits<int(int, float)>::parameter_types>::value,
"");
static_assert(
std::is_same<
bool,
typename make_function_traits_t<bool, typelist::typelist<int, float>>::
return_type>::value,
"");
static_assert(
std::is_same<
void,
typename make_function_traits_t<void, typelist::typelist<int, float>>::
return_type>::value,
"");
static_assert(
std::is_same<
typelist::typelist<int, float>,
typename make_function_traits_t<bool, typelist::typelist<int, float>>::
parameter_types>::value,
"");
static_assert(
std::is_same<
typelist::typelist<int, float>,
typename make_function_traits_t<void, typelist::typelist<int, float>>::
parameter_types>::value,
"");
static_assert(
std::is_same<
bool(int, float),
typename make_function_traits_t<bool, typelist::typelist<int, float>>::
func_type>::value,
"");
static_assert(
std::is_same<
void(int, float),
typename make_function_traits_t<void, typelist::typelist<int, float>>::
func_type>::value,
"");
} // namespace test_function_traits
struct MovableOnly {
constexpr MovableOnly(int val_) : val(val_) { /* no default constructor */
}
MovableOnly(const MovableOnly&) = delete;
MovableOnly(MovableOnly&&) = default;
MovableOnly& operator=(const MovableOnly&) = delete;
MovableOnly& operator=(MovableOnly&&) = default;
friend bool operator==(const MovableOnly& lhs, const MovableOnly& rhs) {
return lhs.val == rhs.val;
}
private:
int val;
};
template <class T>
using is_my_movable_only_class =
std::is_same<MovableOnly, std::remove_cv_t<std::remove_reference_t<T>>>;
struct CopyCounting {
int move_count{0};
int copy_count{0};
CopyCounting() {}
CopyCounting(const CopyCounting& rhs)
: move_count(rhs.move_count), copy_count(rhs.copy_count + 1) {}
CopyCounting(CopyCounting&& rhs) noexcept
: move_count(rhs.move_count + 1), copy_count(rhs.copy_count) {}
CopyCounting& operator=(const CopyCounting& rhs) {
move_count = rhs.move_count;
copy_count = rhs.copy_count + 1;
return *this;
}
CopyCounting& operator=(CopyCounting&& rhs) noexcept {
move_count = rhs.move_count + 1;
copy_count = rhs.copy_count;
return *this;
}
};
template <class T>
using is_my_copy_counting_class =
std::is_same<CopyCounting, std::remove_cv_t<std::remove_reference_t<T>>>;
namespace test_tuple_elements {
// note: not testing empty selection, as some compilers will raise
// "parameter set but not used" in tuple_elements(). a good example
// of the friction that comes with using these tools
TEST(MetaprogrammingTest, TupleElements_subsetSelection) {
auto x = std::make_tuple(0, "HEY", 2.0);
auto y = tuple_elements(x, std::index_sequence<0, 2>());
auto z = std::make_tuple(0, 2.0);
EXPECT_EQ(y, z);
}
TEST(MetaprogrammingTest, TupleElements_reorderSelection) {
auto x = std::make_tuple(0, "HEY", 2.0);
auto y = tuple_elements(x, std::index_sequence<0, 2, 1>());
auto z = std::make_tuple(0, 2.0, "HEY");
EXPECT_EQ(y, z);
}
} // namespace test_tuple_elements
namespace test_tuple_take {
// note: not testing empty prefix, see note on empty selection above.
TEST(MetaprogrammingTest, TupleTake_nonemptyPrefix) {
auto x = std::make_tuple(0, "HEY", 2.0);
auto y = tuple_take<decltype(x), 2>(x);
auto z = std::make_tuple(0, "HEY");
EXPECT_EQ(y, z);
}
TEST(MetaprogrammingTest, TupleTake_fullPrefix) {
auto x = std::make_tuple(0, "HEY", 2.0);
auto y = tuple_take<decltype(x), 3>(x);
EXPECT_EQ(x, y);
}
TEST(MetaprogrammingTest, TupleTake_negative) {
auto x = std::make_tuple(0, "HEY", 2.0);
auto y = tuple_take<decltype(x), -2>(x);
auto z = std::make_tuple("HEY", 2.0);
EXPECT_EQ(y, z);
}
} // namespace test_tuple_take
namespace test_tuple_slice {
TEST(MetaprogrammingTest, TupleSlice_middle) {
auto x = std::make_tuple(0, "HEY", 2.0, false);
auto y = tuple_slice<decltype(x), 1, 2>(x);
auto z = std::make_tuple("HEY", 2.0);
EXPECT_EQ(y, z);
}
TEST(MetaprogrammingTest, TupleSlice_full) {
auto x = std::make_tuple(0, "HEY", 2.0);
auto y = tuple_slice<decltype(x), 0, 3>(x);
EXPECT_EQ(x, y);
}
} // namespace test_tuple_slice
namespace test_tuple_map {
TEST(MetaprogrammingTest, TupleMap_simple) {
auto result = tuple_map(
std::tuple<int32_t, int32_t, int32_t>(3, 4, 5),
[](int32_t a) -> int16_t { return static_cast<int16_t>(a + 1); });
static_assert(
std::is_same<std::tuple<int16_t, int16_t, int16_t>, decltype(result)>::
value,
"");
EXPECT_EQ(4, std::get<0>(result));
EXPECT_EQ(5, std::get<1>(result));
EXPECT_EQ(6, std::get<2>(result));
}
TEST(MetaprogrammingTest, TupleMap_mapperTakesDifferentButConvertibleType) {
auto result = tuple_map(
std::tuple<int32_t, int32_t, int32_t>(3, 4, 5),
[](int64_t a) -> int16_t { return static_cast<int16_t>(a + 1); });
static_assert(
std::is_same<std::tuple<int16_t, int16_t, int16_t>, decltype(result)>::
value,
"");
EXPECT_EQ(4, std::get<0>(result));
EXPECT_EQ(5, std::get<1>(result));
EXPECT_EQ(6, std::get<2>(result));
}
TEST(MetaprogrammingTest, TupleMap_mapperTakesConstRef) {
auto result = tuple_map(
std::tuple<int32_t, int32_t, int32_t>(3, 4, 5),
[](const int32_t& a) -> int16_t { return static_cast<int16_t>(a + 1); });
static_assert(
std::is_same<std::tuple<int16_t, int16_t, int16_t>, decltype(result)>::
value,
"");
EXPECT_EQ(4, std::get<0>(result));
EXPECT_EQ(5, std::get<1>(result));
EXPECT_EQ(6, std::get<2>(result));
}
TEST(MetaprogrammingTest, TupleMap_mapsToDifferentTypes) {
struct Mapper {
std::string operator()(int32_t a) const {
return std::to_string(a);
}
int32_t operator()(const std::string& a) const {
return atoi(a.c_str());
}
};
auto result = tuple_map(std::tuple<int32_t, std::string>(3, "4"), Mapper());
static_assert(
std::is_same<std::tuple<std::string, int32_t>, decltype(result)>::value,
"");
EXPECT_EQ("3", std::get<0>(result));
EXPECT_EQ(4, std::get<1>(result));
}
TEST(MetaprogrammingTest, TupleMap_differentiatesLRValueReferences) {
struct Mapper {
// NOLINTNEXTLINE(*move*)
std::string operator()(std::string&& a) const {
return "moved";
}
std::string operator()(const std::string& a) const {
return "copied";
}
};
std::string str1, str2;
auto result = tuple_map(
std::tuple<const std::string&, std::string&&>(str1, std::move(str2)),
Mapper());
static_assert(
std::is_same<std::tuple<std::string, std::string>, decltype(result)>::
value,
"");
EXPECT_EQ("copied", std::get<0>(result));
EXPECT_EQ("moved", std::get<1>(result));
}
TEST(MetaprogrammingTest, TupleMap_canWorkWithMovableOnlyType) {
auto result = tuple_map(
std::tuple<MovableOnly>(MovableOnly(7)), [](MovableOnly a) { return a; });
static_assert(
std::is_same<std::tuple<MovableOnly>, decltype(result)>::value, "");
EXPECT_EQ(MovableOnly(7), std::get<0>(result));
}
TEST(MetaprogrammingTest, TupleMap_doesntUnecessarilyCopyValues) {
auto result = tuple_map(
std::tuple<CopyCounting>(CopyCounting()),
[](CopyCounting a) { return a; });
static_assert(
std::is_same<std::tuple<CopyCounting>, decltype(result)>::value, "");
EXPECT_EQ(4, std::get<0>(result).move_count);
EXPECT_EQ(0, std::get<0>(result).copy_count);
}
TEST(MetaprogrammingTest, TupleMap_doesntUnecessarilyMoveValues) {
CopyCounting a;
auto result = tuple_map(
std::tuple<CopyCounting&&>(std::move(a)),
[](CopyCounting&& a) -> CopyCounting&& { return std::move(a); });
static_assert(
std::is_same<std::tuple<CopyCounting&&>, decltype(result)>::value, "");
EXPECT_EQ(&a, &std::get<0>(result));
EXPECT_EQ(0, std::get<0>(result).move_count);
EXPECT_EQ(0, std::get<0>(result).copy_count);
}
TEST(MetaprogrammingTest, TupleMap_canBeUsedWithAutoLambdas) {
struct A final {
int32_t func() {
return 5;
}
};
struct B final {
std::string func() {
return "5";
}
};
auto result =
tuple_map(std::make_tuple(A(), B()), [](auto a) { return a.func(); });
static_assert(
std::is_same<std::tuple<int32_t, std::string>, decltype(result)>::value,
"");
EXPECT_EQ(5, std::get<0>(result));
EXPECT_EQ("5", std::get<1>(result));
}
} // namespace test_tuple_map
} // namespace
// NOLINTEND(modernize*, cppcoreguidelines-special-member-functions)
|
