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misterg 2017-09-19 16:54:40 -04:00
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load(
"//absl:copts.bzl",
"ABSL_DEFAULT_COPTS",
"ABSL_TEST_COPTS",
)
package(default_visibility = ["//visibility:public"])
licenses(["unencumbered"]) # Owned by Google
cc_library(
name = "type_traits",
hdrs = ["type_traits.h"],
copts = ABSL_DEFAULT_COPTS,
deps = [
"//absl/base:config",
],
)
cc_test(
name = "type_traits_test",
srcs = ["type_traits_test.cc"],
copts = ABSL_TEST_COPTS,
deps = [
":type_traits",
"//absl/base:core_headers",
"@com_google_googletest//:gtest_main",
],
)

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//
// Copyright 2017 The Abseil Authors.
//
// 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.
//
// -----------------------------------------------------------------------------
// type_traits.h
// -----------------------------------------------------------------------------
//
// This file contains C++11-compatible versions of standard <type_traits> API
// functions for determining the characteristics of types. Such traits can
// support type inference, classification, and transformation, as well as
// make it easier to write templates based on generic type behavior.
//
// See http://en.cppreference.com/w/cpp/header/type_traits
//
// WARNING: use of many of the constructs in this header will count as "complex
// template metaprogramming", so before proceeding, please carefully consider
// https://google.github.io/styleguide/cppguide.html#Template_metaprogramming
//
// WARNING: using template metaprogramming to detect or depend on API
// features is brittle and not guaranteed. Neither the standard library nor
// Abseil provides any guarantee that APIs are stable in the face of template
// metaprogramming. Use with caution.
#ifndef ABSL_META_TYPE_TRAITS_H_
#define ABSL_META_TYPE_TRAITS_H_
#include <type_traits>
#include "absl/base/config.h"
namespace absl {
namespace type_traits_internal {
template <typename... Ts>
struct VoidTImpl {
using type = void;
};
// This trick to retrieve a default alignment is necessary for our
// implementation of aligned_storage_t to be consistent with any implementation
// of std::aligned_storage.
template <size_t Len, typename T = std::aligned_storage<Len>>
struct default_alignment_of_aligned_storage;
template <size_t Len, size_t Align>
struct default_alignment_of_aligned_storage<Len,
std::aligned_storage<Len, Align>> {
static constexpr size_t value = Align;
};
} // namespace type_traits_internal
// void_t()
//
// Ignores the type of any its arguments and returns `void`. In general, this
// metafunction allows you to create a general case that maps to `void` while
// allowing specializations that map to specific types.
//
// This metafunction is designed to be a drop-in replacement for the C++17
// `std::void_t` metafunction.
//
// NOTE: `absl::void_t` does not use the standard-specified implementation so
// that it can remain compatibile with gcc < 5.1. This can introduce slightly
// different behavior, such as when ordering partial specializations.
template <typename... Ts>
using void_t = typename type_traits_internal::VoidTImpl<Ts...>::type;
// conjunction
//
// Performs a compile-time logical AND operation on the passed types (which
// must have `::value` members convertible to `bool`. Short-circuits if it
// encounters any `false` members (and does not compare the `::value` members
// of any remaining arguments).
//
// This metafunction is designed to be a drop-in replacement for the C++17
// `std::conjunction` metafunction.
template <typename... Ts>
struct conjunction;
template <typename T, typename... Ts>
struct conjunction<T, Ts...>
: std::conditional<T::value, conjunction<Ts...>, T>::type {};
template <typename T>
struct conjunction<T> : T {};
template <>
struct conjunction<> : std::true_type {};
// disjunction
//
// Performs a compile-time logical OR operation on the passed types (which
// must have `::value` members convertible to `bool`. Short-circuits if it
// encounters any `true` members (and does not compare the `::value` members
// of any remaining arguments).
//
// This metafunction is designed to be a drop-in replacement for the C++17
// `std::disjunction` metafunction.
template <typename... Ts>
struct disjunction;
template <typename T, typename... Ts>
struct disjunction<T, Ts...> :
std::conditional<T::value, T, disjunction<Ts...>>::type {};
template <typename T>
struct disjunction<T> : T {};
template <>
struct disjunction<> : std::false_type {};
// negation
//
// Performs a compile-time logical NOT operation on the passed type (which
// must have `::value` members convertible to `bool`.
//
// This metafunction is designed to be a drop-in replacement for the C++17
// `std::negation` metafunction.
template <typename T>
struct negation : std::integral_constant<bool, !T::value> {};
// is_trivially_destructible()
//
// Determines whether the passed type `T` is trivially destructable.
//
// This metafunction is designed to be a drop-in replacement for the C++17
// `std::is_trivially_destructible()` metafunction.
//
// NOTE: the extensions (__has_trivial_xxx) are implemented in gcc (version >=
// 4.3) and clang. Since we are supporting libstdc++ > 4.7, they should always
// be present. These extensions are documented at
// https://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html#Type-Traits.
template <typename T>
struct is_trivially_destructible
: std::integral_constant<bool, __has_trivial_destructor(T) &&
std::is_destructible<T>::value> {
#ifdef ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE
static_assert(std::is_trivially_destructible<T>::value ==
is_trivially_destructible::value,
"Not compliant with std::is_trivially_destructible");
#endif // ABSL_HAVE_STD_IS_TRIVIALLY_DESTRUCTIBLE
};
// is_trivially_default_constructible()
//
// Determines whether the passed type `T` is trivially default constructible.
//
// This metafunction is designed to be a drop-in replacement for the C++17
// `std::is_trivially_default_constructible()` metafunction.
//
// NOTE: according to the C++ standard, Section: 20.15.4.3 [meta.unary.prop]
// "The predicate condition for a template specialization is_constructible<T,
// Args...> shall be satisfied if and only if the following variable
// definition would be well-formed for some invented variable t:
//
// T t(declval<Args>()...);
//
// is_trivially_constructible<T, Args...> additionally requires that the
// variable definition does not call any operation that is not trivial.
// For the purposes of this check, the call to std::declval is considered
// trivial."
//
// Notes from http://en.cppreference.com/w/cpp/types/is_constructible:
// In many implementations, is_nothrow_constructible also checks if the
// destructor throws because it is effectively noexcept(T(arg)). Same
// applies to is_trivially_constructible, which, in these implementations, also
// requires that the destructor is trivial.
// GCC bug 51452: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=51452
// LWG issue 2116: http://cplusplus.github.io/LWG/lwg-active.html#2116.
//
// "T obj();" need to be well-formed and not call any non-trivial operation.
// Nontrivally destructible types will cause the expression to be nontrivial.
template <typename T>
struct is_trivially_default_constructible
: std::integral_constant<bool,
__has_trivial_constructor(T) &&
std::is_default_constructible<T>::value &&
is_trivially_destructible<T>::value> {
#ifdef ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE
static_assert(std::is_trivially_default_constructible<T>::value ==
is_trivially_default_constructible::value,
"Not compliant with std::is_trivially_default_constructible");
#endif // ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE
};
// is_trivially_copy_constructible()
//
// Determines whether the passed type `T` is trivially copy constructible.
//
// This metafunction is designed to be a drop-in replacement for the C++17
// `std::is_trivially_copy_constructible()` metafunction.
//
// NOTE: `T obj(declval<const T&>());` needs to be well-formed and not call any
// nontrivial operation. Nontrivally destructible types will cause the
// expression to be nontrivial.
template <typename T>
struct is_trivially_copy_constructible
: std::integral_constant<bool, __has_trivial_copy(T) &&
std::is_copy_constructible<T>::value &&
is_trivially_destructible<T>::value> {
#ifdef ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE
static_assert(std::is_trivially_copy_constructible<T>::value ==
is_trivially_copy_constructible::value,
"Not compliant with std::is_trivially_copy_constructible");
#endif // ABSL_HAVE_STD_IS_TRIVIALLY_CONSTRUCTIBLE
};
// is_trivially_copy_assignable()
//
// Determines whether the passed type `T` is trivially copy assignable.
//
// This metafunction is designed to be a drop-in replacement for the C++17
// `std::is_trivially_copy_assignable()` metafunction.
//
// NOTE: `is_assignable<T, U>::value` is `true` if the expression
// `declval<T>() = declval<U>()` is well-formed when treated as an unevaluated
// operand. `is_trivially_assignable<T, U>` requires the assignment to call no
// operation that is not trivial. `is_trivially_copy_assignable<T>` is simply
// `is_trivially_assignable<T, const T&>`.
template <typename T>
struct is_trivially_copy_assignable
: std::integral_constant<bool, __has_trivial_assign(T) &&
std::is_copy_assignable<T>::value> {
#ifdef ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE
static_assert(std::is_trivially_copy_assignable<T>::value ==
is_trivially_copy_assignable::value,
"Not compliant with std::is_trivially_copy_assignable");
#endif // ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE
};
// -----------------------------------------------------------------------------
// C++14 "_t" trait aliases
// -----------------------------------------------------------------------------
template <typename T>
using remove_cv_t = typename std::remove_cv<T>::type;
template <typename T>
using remove_const_t = typename std::remove_const<T>::type;
template <typename T>
using remove_volatile_t = typename std::remove_volatile<T>::type;
template <typename T>
using add_cv_t = typename std::add_cv<T>::type;
template <typename T>
using add_const_t = typename std::add_const<T>::type;
template <typename T>
using add_volatile_t = typename std::add_volatile<T>::type;
template <typename T>
using remove_reference_t = typename std::remove_reference<T>::type;
template <typename T>
using add_lvalue_reference_t = typename std::add_lvalue_reference<T>::type;
template <typename T>
using add_rvalue_reference_t = typename std::add_rvalue_reference<T>::type;
template <typename T>
using remove_pointer_t = typename std::remove_pointer<T>::type;
template <typename T>
using add_pointer_t = typename std::add_pointer<T>::type;
template <typename T>
using make_signed_t = typename std::make_signed<T>::type;
template <typename T>
using make_unsigned_t = typename std::make_unsigned<T>::type;
template <typename T>
using remove_extent_t = typename std::remove_extent<T>::type;
template <typename T>
using remove_all_extents_t = typename std::remove_all_extents<T>::type;
template <size_t Len, size_t Align = type_traits_internal::
default_alignment_of_aligned_storage<Len>::value>
using aligned_storage_t = typename std::aligned_storage<Len, Align>::type;
template <typename T>
using decay_t = typename std::decay<T>::type;
template <bool B, typename T = void>
using enable_if_t = typename std::enable_if<B, T>::type;
template <bool B, typename T, typename F>
using conditional_t = typename std::conditional<B, T, F>::type;
template <typename... T>
using common_type_t = typename std::common_type<T...>::type;
template <typename T>
using underlying_type_t = typename std::underlying_type<T>::type;
template <typename T>
using result_of_t = typename std::result_of<T>::type;
} // namespace absl
#endif // ABSL_META_TYPE_TRAITS_H_

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// Copyright 2017 The Abseil Authors.
//
// 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.
#include "absl/meta/type_traits.h"
#include <cstdint>
#include <string>
#include <type_traits>
#include <vector>
#include "gmock/gmock.h"
#include "gtest/gtest.h"
namespace {
using ::testing::StaticAssertTypeEq;
struct Dummy {};
TEST(VoidTTest, BasicUsage) {
StaticAssertTypeEq<void, absl::void_t<Dummy>>();
StaticAssertTypeEq<void, absl::void_t<Dummy, Dummy, Dummy>>();
}
TEST(ConjunctionTest, BasicBooleanLogic) {
EXPECT_TRUE(absl::conjunction<>::value);
EXPECT_TRUE(absl::conjunction<std::true_type>::value);
EXPECT_TRUE((absl::conjunction<std::true_type, std::true_type>::value));
EXPECT_FALSE((absl::conjunction<std::true_type, std::false_type>::value));
EXPECT_FALSE((absl::conjunction<std::false_type, std::true_type>::value));
EXPECT_FALSE((absl::conjunction<std::false_type, std::false_type>::value));
}
struct MyTrueType {
static constexpr bool value = true;
};
struct MyFalseType {
static constexpr bool value = false;
};
TEST(ConjunctionTest, ShortCircuiting) {
EXPECT_FALSE(
(absl::conjunction<std::true_type, std::false_type, Dummy>::value));
EXPECT_TRUE((std::is_base_of<MyFalseType,
absl::conjunction<std::true_type, MyFalseType,
std::false_type>>::value));
EXPECT_TRUE(
(std::is_base_of<MyTrueType,
absl::conjunction<std::true_type, MyTrueType>>::value));
}
TEST(DisjunctionTest, BasicBooleanLogic) {
EXPECT_FALSE(absl::disjunction<>::value);
EXPECT_FALSE(absl::disjunction<std::false_type>::value);
EXPECT_TRUE((absl::disjunction<std::true_type, std::true_type>::value));
EXPECT_TRUE((absl::disjunction<std::true_type, std::false_type>::value));
EXPECT_TRUE((absl::disjunction<std::false_type, std::true_type>::value));
EXPECT_FALSE((absl::disjunction<std::false_type, std::false_type>::value));
}
TEST(DisjunctionTest, ShortCircuiting) {
EXPECT_TRUE(
(absl::disjunction<std::false_type, std::true_type, Dummy>::value));
EXPECT_TRUE((
std::is_base_of<MyTrueType, absl::disjunction<std::false_type, MyTrueType,
std::true_type>>::value));
EXPECT_TRUE((
std::is_base_of<MyFalseType,
absl::disjunction<std::false_type, MyFalseType>>::value));
}
TEST(NegationTest, BasicBooleanLogic) {
EXPECT_FALSE(absl::negation<std::true_type>::value);
EXPECT_FALSE(absl::negation<MyTrueType>::value);
EXPECT_TRUE(absl::negation<std::false_type>::value);
EXPECT_TRUE(absl::negation<MyFalseType>::value);
}
// all member functions are trivial
class Trivial {
int n_;
};
class TrivialDefaultCtor {
public:
TrivialDefaultCtor() = default;
explicit TrivialDefaultCtor(int n) : n_(n) {}
private:
int n_;
};
class TrivialCopyCtor {
public:
explicit TrivialCopyCtor(int n) : n_(n) {}
TrivialCopyCtor(const TrivialCopyCtor&) = default;
TrivialCopyCtor& operator=(const TrivialCopyCtor& t) {
n_ = t.n_;
return *this;
}
private:
int n_;
};
class TrivialCopyAssign {
public:
explicit TrivialCopyAssign(int n) : n_(n) {}
TrivialCopyAssign(const TrivialCopyAssign& t) : n_(t.n_) {}
TrivialCopyAssign& operator=(const TrivialCopyAssign& t) = default;
~TrivialCopyAssign() {} // can have non trivial destructor
private:
int n_;
};
struct NonTrivialDestructor {
~NonTrivialDestructor() {}
};
struct TrivialDestructor {
~TrivialDestructor() = default;
};
struct NonCopyable {
NonCopyable() = default;
NonCopyable(const NonCopyable&) = delete;
NonCopyable& operator=(const NonCopyable&) = delete;
};
class Base {
public:
virtual ~Base() {}
};
// In GCC/Clang, std::is_trivially_constructible requires that the destructor is
// trivial. However, MSVC doesn't require that. This results in different
// behavior when checking is_trivially_constructible on any type with nontrivial
// destructor. Since absl::is_trivially_default_constructible and
// absl::is_trivially_copy_constructible both follows Clang/GCC's interpretation
// and check is_trivially_destructible, it results in inconsistency with
// std::is_trivially_xxx_constructible on MSVC. This macro is used to work
// around this issue in test. In practice, a trivially constructible type
// should also be trivially destructible.
// GCC bug 51452: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=51452
// LWG issue 2116: http://cplusplus.github.io/LWG/lwg-active.html#2116.
#ifdef _MSC_VER
#define ABSL_TRIVIALLY_CONSTRUCTIBLE_VERIFY_TRIVIALLY_DESTRUCTIBLE
#endif
TEST(TypeTraitsTest, TestTrivialDefaultCtor) {
// arithmetic types and pointers have trivial default constructors.
EXPECT_TRUE(absl::is_trivially_default_constructible<bool>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<char>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<unsigned char>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<signed char>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<wchar_t>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<int>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<unsigned int>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<int16_t>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<uint16_t>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<int64_t>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<uint64_t>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<float>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<double>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<long double>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<std::string*>::value);
EXPECT_TRUE(absl::is_trivially_default_constructible<Trivial*>::value);
EXPECT_TRUE(
absl::is_trivially_default_constructible<const TrivialCopyCtor*>::value);
EXPECT_TRUE(
absl::is_trivially_default_constructible<TrivialCopyCtor**>::value);
// types with compiler generated default ctors
EXPECT_TRUE(absl::is_trivially_default_constructible<Trivial>::value);
EXPECT_TRUE(
absl::is_trivially_default_constructible<TrivialDefaultCtor>::value);
#ifndef ABSL_TRIVIALLY_CONSTRUCTIBLE_VERIFY_TRIVIALLY_DESTRUCTIBLE
// types with non trivial destructor are non trivial
EXPECT_FALSE(
absl::is_trivially_default_constructible<NonTrivialDestructor>::value);
#endif
// types with vtables
EXPECT_FALSE(absl::is_trivially_default_constructible<Base>::value);
// Verify that arrays of such types are trivially default constructible
typedef int int10[10];
EXPECT_TRUE(absl::is_trivially_default_constructible<int10>::value);
typedef Trivial Trivial10[10];
EXPECT_TRUE(absl::is_trivially_default_constructible<Trivial10>::value);
typedef Trivial TrivialDefaultCtor10[10];
EXPECT_TRUE(
absl::is_trivially_default_constructible<TrivialDefaultCtor10>::value);
// Verify that std::pair has non-trivial constructors.
EXPECT_FALSE(
(absl::is_trivially_default_constructible<std::pair<int, char*>>::value));
// Verify that types without trivial constructors are
// correctly marked as such.
EXPECT_FALSE(absl::is_trivially_default_constructible<std::string>::value);
EXPECT_FALSE(
absl::is_trivially_default_constructible<std::vector<int>>::value);
}
TEST(TypeTraitsTest, TestTrivialCopyCtor) {
// Verify that arithmetic types and pointers have trivial copy
// constructors.
EXPECT_TRUE(absl::is_trivially_copy_constructible<bool>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<char>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<unsigned char>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<signed char>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<wchar_t>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<int>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<unsigned int>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<int16_t>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<uint16_t>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<int64_t>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<uint64_t>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<float>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<double>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<long double>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<std::string*>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<Trivial*>::value);
EXPECT_TRUE(
absl::is_trivially_copy_constructible<const TrivialCopyCtor*>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<TrivialCopyCtor**>::value);
// types with compiler generated copy ctors
EXPECT_TRUE(absl::is_trivially_copy_constructible<Trivial>::value);
EXPECT_TRUE(absl::is_trivially_copy_constructible<TrivialCopyCtor>::value);
#ifndef ABSL_TRIVIALLY_CONSTRUCTIBLE_VERIFY_TRIVIALLY_DESTRUCTIBLE
// type with non-trivial destructor are non-trivial copy construbtible
EXPECT_FALSE(
absl::is_trivially_copy_constructible<NonTrivialDestructor>::value);
#endif
// types with vtables
EXPECT_FALSE(absl::is_trivially_copy_constructible<Base>::value);
// Verify that std pair of such types is trivially copy constructible
EXPECT_TRUE(
(absl::is_trivially_copy_constructible<std::pair<int, char*>>::value));
EXPECT_TRUE(
(absl::is_trivially_copy_constructible<std::pair<int, Trivial>>::value));
EXPECT_TRUE((absl::is_trivially_copy_constructible<
std::pair<int, TrivialCopyCtor>>::value));
// Verify that arrays are not
typedef int int10[10];
EXPECT_FALSE(absl::is_trivially_copy_constructible<int10>::value);
// Verify that pairs of types without trivial copy constructors
// are not marked as trivial.
EXPECT_FALSE((absl::is_trivially_copy_constructible<
std::pair<int, std::string>>::value));
EXPECT_FALSE((absl::is_trivially_copy_constructible<
std::pair<std::string, int>>::value));
// Verify that types without trivial copy constructors are
// correctly marked as such.
EXPECT_FALSE(absl::is_trivially_copy_constructible<std::string>::value);
EXPECT_FALSE(absl::is_trivially_copy_constructible<std::vector<int>>::value);
// types with deleted copy constructors are not copy constructible
EXPECT_FALSE(absl::is_trivially_copy_constructible<NonCopyable>::value);
}
TEST(TypeTraitsTest, TestTrivialCopyAssign) {
// Verify that arithmetic types and pointers have trivial copy
// constructors.
EXPECT_TRUE(absl::is_trivially_copy_assignable<bool>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<char>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<unsigned char>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<signed char>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<wchar_t>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<int>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<unsigned int>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<int16_t>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<uint16_t>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<int64_t>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<uint64_t>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<float>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<double>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<long double>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<std::string*>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<Trivial*>::value);
EXPECT_TRUE(
absl::is_trivially_copy_assignable<const TrivialCopyCtor*>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<TrivialCopyCtor**>::value);
// const qualified types are not assignable
EXPECT_FALSE(absl::is_trivially_copy_assignable<const int>::value);
// types with compiler generated copy assignment
EXPECT_TRUE(absl::is_trivially_copy_assignable<Trivial>::value);
EXPECT_TRUE(absl::is_trivially_copy_assignable<TrivialCopyAssign>::value);
// types with vtables
EXPECT_FALSE(absl::is_trivially_copy_assignable<Base>::value);
// Verify that arrays are not trivially copy assignable
typedef int int10[10];
EXPECT_FALSE(absl::is_trivially_copy_assignable<int10>::value);
// Verify that std::pair is not trivially assignable
EXPECT_FALSE(
(absl::is_trivially_copy_assignable<std::pair<int, char*>>::value));
// Verify that types without trivial copy constructors are
// correctly marked as such.
EXPECT_FALSE(absl::is_trivially_copy_assignable<std::string>::value);
EXPECT_FALSE(absl::is_trivially_copy_assignable<std::vector<int>>::value);
// types with deleted copy assignment are not copy assignable
EXPECT_FALSE(absl::is_trivially_copy_assignable<NonCopyable>::value);
}
TEST(TypeTraitsTest, TestTrivialDestructor) {
// Verify that arithmetic types and pointers have trivial copy
// constructors.
EXPECT_TRUE(absl::is_trivially_destructible<bool>::value);
EXPECT_TRUE(absl::is_trivially_destructible<char>::value);
EXPECT_TRUE(absl::is_trivially_destructible<unsigned char>::value);
EXPECT_TRUE(absl::is_trivially_destructible<signed char>::value);
EXPECT_TRUE(absl::is_trivially_destructible<wchar_t>::value);
EXPECT_TRUE(absl::is_trivially_destructible<int>::value);
EXPECT_TRUE(absl::is_trivially_destructible<unsigned int>::value);
EXPECT_TRUE(absl::is_trivially_destructible<int16_t>::value);
EXPECT_TRUE(absl::is_trivially_destructible<uint16_t>::value);
EXPECT_TRUE(absl::is_trivially_destructible<int64_t>::value);
EXPECT_TRUE(absl::is_trivially_destructible<uint64_t>::value);
EXPECT_TRUE(absl::is_trivially_destructible<float>::value);
EXPECT_TRUE(absl::is_trivially_destructible<double>::value);
EXPECT_TRUE(absl::is_trivially_destructible<long double>::value);
EXPECT_TRUE(absl::is_trivially_destructible<std::string*>::value);
EXPECT_TRUE(absl::is_trivially_destructible<Trivial*>::value);
EXPECT_TRUE(absl::is_trivially_destructible<const TrivialCopyCtor*>::value);
EXPECT_TRUE(absl::is_trivially_destructible<TrivialCopyCtor**>::value);
// classes with destructors
EXPECT_TRUE(absl::is_trivially_destructible<Trivial>::value);
EXPECT_TRUE(absl::is_trivially_destructible<TrivialDestructor>::value);
EXPECT_FALSE(absl::is_trivially_destructible<NonTrivialDestructor>::value);
// std::pair of such types is trivial
EXPECT_TRUE((absl::is_trivially_destructible<std::pair<int, int>>::value));
EXPECT_TRUE((absl::is_trivially_destructible<
std::pair<Trivial, TrivialDestructor>>::value));
// array of such types is trivial
typedef int int10[10];
EXPECT_TRUE(absl::is_trivially_destructible<int10>::value);
typedef TrivialDestructor TrivialDestructor10[10];
EXPECT_TRUE(absl::is_trivially_destructible<TrivialDestructor10>::value);
typedef NonTrivialDestructor NonTrivialDestructor10[10];
EXPECT_FALSE(absl::is_trivially_destructible<NonTrivialDestructor10>::value);
}
#define ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(trait_name, ...) \
EXPECT_TRUE((std::is_same<typename std::trait_name<__VA_ARGS__>::type, \
absl::trait_name##_t<__VA_ARGS__>>::value))
TEST(TypeTraitsTest, TestRemoveCVAliases) {
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_cv, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_cv, const int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_cv, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_cv, const volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_const, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_const, const int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_const, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_const, const volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_volatile, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_volatile, const int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_volatile, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_volatile, const volatile int);
}
TEST(TypeTraitsTest, TestAddCVAliases) {
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_cv, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_cv, const int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_cv, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_cv, const volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_const, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_const, const int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_const, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_const, const volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_volatile, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_volatile, const int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_volatile, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_volatile, const volatile int);
}
TEST(TypeTraitsTest, TestReferenceAliases) {
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_reference, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_reference, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_reference, int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_reference, volatile int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_reference, int&&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_reference, volatile int&&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_lvalue_reference, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_lvalue_reference, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_lvalue_reference, int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_lvalue_reference, volatile int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_lvalue_reference, int&&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_lvalue_reference, volatile int&&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_rvalue_reference, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_rvalue_reference, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_rvalue_reference, int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_rvalue_reference, volatile int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_rvalue_reference, int&&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_rvalue_reference, volatile int&&);
}
TEST(TypeTraitsTest, TestPointerAliases) {
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_pointer, int*);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_pointer, volatile int*);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_pointer, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(add_pointer, volatile int);
}
TEST(TypeTraitsTest, TestSignednessAliases) {
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(make_signed, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(make_signed, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(make_signed, unsigned);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(make_signed, volatile unsigned);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(make_unsigned, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(make_unsigned, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(make_unsigned, unsigned);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(make_unsigned, volatile unsigned);
}
TEST(TypeTraitsTest, TestExtentAliases) {
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_extent, int[]);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_extent, int[1]);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_extent, int[1][1]);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_extent, int[][1]);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_all_extents, int[]);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_all_extents, int[1]);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_all_extents, int[1][1]);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(remove_all_extents, int[][1]);
}
TEST(TypeTraitsTest, TestAlignedStorageAlias) {
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 1);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 2);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 3);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 4);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 5);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 6);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 7);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 8);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 9);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 10);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 11);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 12);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 13);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 14);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 15);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 16);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 17);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 18);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 19);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 20);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 21);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 22);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 23);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 24);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 25);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 26);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 27);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 28);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 29);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 30);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 31);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 32);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 33);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 1, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 2, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 3, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 4, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 5, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 6, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 7, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 8, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 9, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 10, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 11, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 12, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 13, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 14, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 15, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 16, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 17, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 18, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 19, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 20, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 21, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 22, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 23, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 24, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 25, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 26, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 27, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 28, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 29, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 30, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 31, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 32, 128);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(aligned_storage, 33, 128);
}
TEST(TypeTraitsTest, TestDecay) {
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, const int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, const volatile int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, const int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, volatile int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, const volatile int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, const int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, volatile int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, const volatile int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int[1]);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int[1][1]);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int[][1]);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int());
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int(float));
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(decay, int(char, ...));
}
struct TypeA {};
struct TypeB {};
struct TypeC {};
struct TypeD {};
template <typename T>
struct Wrap {};
enum class TypeEnum { A, B, C, D };
struct GetTypeT {
template <typename T,
absl::enable_if_t<std::is_same<T, TypeA>::value, int> = 0>
TypeEnum operator()(Wrap<T>) const {
return TypeEnum::A;
}
template <typename T,
absl::enable_if_t<std::is_same<T, TypeB>::value, int> = 0>
TypeEnum operator()(Wrap<T>) const {
return TypeEnum::B;
}
template <typename T,
absl::enable_if_t<std::is_same<T, TypeC>::value, int> = 0>
TypeEnum operator()(Wrap<T>) const {
return TypeEnum::C;
}
// NOTE: TypeD is intentionally not handled
} constexpr GetType = {};
TEST(TypeTraitsTest, TestEnableIf) {
EXPECT_EQ(TypeEnum::A, GetType(Wrap<TypeA>()));
EXPECT_EQ(TypeEnum::B, GetType(Wrap<TypeB>()));
EXPECT_EQ(TypeEnum::C, GetType(Wrap<TypeC>()));
}
TEST(TypeTraitsTest, TestConditional) {
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(conditional, true, int, char);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(conditional, false, int, char);
}
// TODO(calabrese) Check with specialized std::common_type
TEST(TypeTraitsTest, TestCommonType) {
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(common_type, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(common_type, int, char);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(common_type, int, char, int);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(common_type, int&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(common_type, int, char&);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(common_type, int, char, int&);
}
TEST(TypeTraitsTest, TestUnderlyingType) {
enum class enum_char : char {};
enum class enum_long_long : long long {}; // NOLINT(runtime/int)
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(underlying_type, enum_char);
ABSL_INTERNAL_EXPECT_ALIAS_EQUIVALENCE(underlying_type, enum_long_long);
}
struct GetTypeExtT {
template <typename T>
absl::result_of_t<const GetTypeT&(T)> operator()(T&& arg) const {
return GetType(std::forward<T>(arg));
}
TypeEnum operator()(Wrap<TypeD>) const { return TypeEnum::D; }
} constexpr GetTypeExt = {};
TEST(TypeTraitsTest, TestResultOf) {
EXPECT_EQ(TypeEnum::A, GetTypeExt(Wrap<TypeA>()));
EXPECT_EQ(TypeEnum::B, GetTypeExt(Wrap<TypeB>()));
EXPECT_EQ(TypeEnum::C, GetTypeExt(Wrap<TypeC>()));
EXPECT_EQ(TypeEnum::D, GetTypeExt(Wrap<TypeD>()));
}
} // namespace