| // Copyright 2018 The Fuchsia Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include <string> |
| #include <type_traits> |
| |
| #include <lib/fit/variant.h> |
| #include <unittest/unittest.h> |
| |
| namespace { |
| |
| struct no_copy { |
| no_copy(const no_copy&) = delete; |
| no_copy(no_copy&&) = default; |
| no_copy& operator=(const no_copy&) = delete; |
| no_copy& operator=(no_copy&&) = default; |
| }; |
| |
| struct no_move { |
| no_move(const no_move&) = default; |
| no_move(no_move&&) = delete; |
| no_move& operator=(const no_move&) = default; |
| no_move& operator=(no_move&&) = delete; |
| }; |
| |
| struct no_copy_no_move { |
| no_copy_no_move(const no_copy_no_move&) = delete; |
| no_copy_no_move(no_copy_no_move&&) = delete; |
| no_copy_no_move& operator=(const no_copy_no_move&) = delete; |
| no_copy_no_move& operator=(no_copy_no_move&&) = delete; |
| }; |
| |
| struct non_trivial_destructor { |
| ~non_trivial_destructor() {} |
| }; |
| |
| struct non_trivial_copy { |
| non_trivial_copy(const non_trivial_copy&) {} |
| non_trivial_copy(non_trivial_copy&&) = default; |
| non_trivial_copy& operator=(const non_trivial_copy&) { return *this; } |
| non_trivial_copy& operator=(non_trivial_copy&&) = default; |
| }; |
| |
| struct non_trivial_move { |
| non_trivial_move(const non_trivial_move&) = default; |
| non_trivial_move(non_trivial_move&&) {} |
| non_trivial_move& operator=(const non_trivial_move&) = default; |
| non_trivial_move& operator=(non_trivial_move&&) { return *this; } |
| }; |
| |
| struct literal_traits { |
| using variant = fit::internal::variant< |
| fit::internal::monostate, int, double>; |
| |
| static constexpr fit::internal::monostate a_value{}; |
| static constexpr int b_value = 10; |
| static constexpr double c_value = 2.5; |
| static constexpr double c2_value = 4.2; |
| |
| static variant a, b, c; |
| static constexpr variant const_a; |
| static constexpr variant const_b{fit::internal::in_place_index<1>, |
| b_value}; |
| static constexpr variant const_c{fit::internal::in_place_index<2>, |
| c_value}; |
| }; |
| |
| literal_traits::variant literal_traits::a; |
| literal_traits::variant literal_traits::b{fit::internal::in_place_index<1>, |
| literal_traits::b_value}; |
| literal_traits::variant literal_traits::c{fit::internal::in_place_index<2>, |
| literal_traits::c_value}; |
| |
| struct complex_traits { |
| using variant = fit::internal::variant< |
| fit::internal::monostate, int, std::string>; |
| |
| static const fit::internal::monostate a_value; |
| static const int b_value; |
| static const std::string c_value; |
| static const std::string c2_value; |
| |
| static variant a, b, c; |
| static const variant const_a; |
| static const variant const_b; |
| static const variant const_c; |
| }; |
| |
| const fit::internal::monostate complex_traits::a_value{}; |
| const int complex_traits::b_value = 10; |
| const std::string complex_traits::c_value = "test"; |
| const std::string complex_traits::c2_value = "another"; |
| |
| complex_traits::variant complex_traits::a; |
| complex_traits::variant complex_traits::b{fit::internal::in_place_index<1>, |
| complex_traits::b_value}; |
| complex_traits::variant complex_traits::c{fit::internal::in_place_index<2>, |
| complex_traits::c_value}; |
| |
| const complex_traits::variant complex_traits::const_a; |
| const complex_traits::variant complex_traits::const_b{fit::internal::in_place_index<1>, |
| complex_traits::b_value}; |
| const complex_traits::variant complex_traits::const_c{fit::internal::in_place_index<2>, |
| complex_traits::c_value}; |
| |
| template <typename T> |
| bool accessors() { |
| BEGIN_TEST; |
| |
| EXPECT_EQ(0, T::a.index()); |
| EXPECT_TRUE(T::a_value == T::a.template get<0>()); |
| EXPECT_TRUE(T::a_value == T::const_a.template get<0>()); |
| |
| EXPECT_EQ(1, T::b.index()); |
| EXPECT_TRUE(T::b_value == T::b.template get<1>()); |
| EXPECT_TRUE(T::b_value == T::const_b.template get<1>()); |
| |
| EXPECT_EQ(2, T::c.index()); |
| EXPECT_TRUE(T::c_value == T::c.template get<2>()); |
| EXPECT_TRUE(T::c_value == T::const_c.template get<2>()); |
| |
| END_TEST; |
| } |
| |
| template <typename T> |
| bool copy_move_assign() { |
| BEGIN_TEST; |
| |
| typename T::variant x; |
| EXPECT_EQ(0, x.index()); |
| EXPECT_TRUE(T::a_value == x.template get<0>()); |
| |
| x = T::b; |
| EXPECT_EQ(1, x.index()); |
| EXPECT_TRUE(T::b_value == x.template get<1>()); |
| |
| x.template emplace<2>(T::c_value); |
| EXPECT_EQ(2, x.index()); |
| EXPECT_TRUE(T::c_value == x.template get<2>()); |
| |
| typename T::variant y(T::b); |
| EXPECT_EQ(1, y.index()); |
| EXPECT_TRUE(T::b_value == y.template get<1>()); |
| |
| x = std::move(y); |
| EXPECT_EQ(1, x.index()); |
| EXPECT_TRUE(T::b_value == x.template get<1>()); |
| |
| x = x; |
| EXPECT_EQ(1, x.index()); |
| EXPECT_TRUE(T::b_value == x.template get<1>()); |
| |
| x = std::move(x); |
| EXPECT_EQ(1, x.index()); |
| EXPECT_TRUE(T::b_value == x.template get<1>()); |
| |
| x = T::a; |
| EXPECT_EQ(0, x.index()); |
| EXPECT_TRUE(T::a_value == x.template get<0>()); |
| |
| x = T::c; |
| typename T::variant z(std::move(x)); |
| EXPECT_EQ(2, z.index()); |
| EXPECT_TRUE(T::c_value == z.template get<2>()); |
| |
| END_TEST; |
| } |
| |
| template <typename T> |
| bool swapping() { |
| BEGIN_TEST; |
| |
| typename T::variant x; |
| EXPECT_EQ(0, x.index()); |
| EXPECT_TRUE(T::a_value == x.template get<0>()); |
| |
| typename T::variant y(T::c); |
| y.swap(y); |
| EXPECT_EQ(2, y.index()); |
| EXPECT_TRUE(T::c_value == y.template get<2>()); |
| |
| x.swap(y); |
| EXPECT_EQ(2, x.index()); |
| EXPECT_TRUE(T::c_value == x.template get<2>()); |
| EXPECT_EQ(0, y.index()); |
| EXPECT_TRUE(T::a_value == y.template get<0>()); |
| |
| y.template emplace<2>(T::c2_value); |
| x.swap(y); |
| EXPECT_EQ(2, x.index()); |
| EXPECT_TRUE(T::c2_value == x.template get<2>()); |
| EXPECT_EQ(2, y.index()); |
| EXPECT_TRUE(T::c_value == y.template get<2>()); |
| |
| x = T::b; |
| y.swap(x); |
| EXPECT_EQ(2, x.index()); |
| EXPECT_TRUE(T::c_value == x.template get<2>()); |
| EXPECT_EQ(1, y.index()); |
| EXPECT_TRUE(T::b_value == y.template get<1>()); |
| |
| x = T::a; |
| y.swap(x); |
| EXPECT_EQ(1, x.index()); |
| EXPECT_TRUE(T::b_value == x.template get<1>()); |
| EXPECT_EQ(0, y.index()); |
| EXPECT_TRUE(T::a_value == y.template get<0>()); |
| |
| END_TEST; |
| } |
| |
| // Test constexpr behavior. |
| namespace constexpr_test { |
| static_assert(literal_traits::variant().index() == 0, ""); |
| static_assert(literal_traits::const_a.index() == 0, ""); |
| static_assert(literal_traits::const_a.get<0>() == literal_traits::a_value, ""); |
| static_assert(literal_traits::const_b.index() == 1, ""); |
| static_assert(literal_traits::const_b.get<1>() == literal_traits::b_value, ""); |
| static_assert(literal_traits::const_c.index() == 2, ""); |
| static_assert(literal_traits::const_c.get<2>() == literal_traits::c_value, ""); |
| } // namespace constexpr_test |
| |
| // Ensure the variant is copy-constructible only when the types are copyable. |
| namespace copy_construction_test { |
| static_assert( |
| std::is_copy_constructible< |
| fit::internal::variant<fit::internal::monostate>>::value, |
| ""); |
| static_assert( |
| !std::is_copy_constructible< |
| fit::internal::variant<fit::internal::monostate, no_copy>>::value, |
| ""); |
| static_assert( |
| std::is_copy_constructible< |
| fit::internal::variant<fit::internal::monostate, no_move>>::value, |
| ""); |
| static_assert( |
| !std::is_copy_constructible< |
| fit::internal::variant<fit::internal::monostate, no_copy_no_move>>::value, |
| ""); |
| static_assert( |
| std::is_copy_constructible< |
| literal_traits::variant>::value, |
| ""); |
| static_assert( |
| std::is_copy_constructible< |
| complex_traits::variant>::value, |
| ""); |
| } // namespace copy_construction_test |
| |
| // Ensure the variant is copy-assignable only when the types are copyable. |
| namespace copy_assignment_test { |
| static_assert( |
| std::is_copy_assignable< |
| fit::internal::variant<fit::internal::monostate>>::value, |
| ""); |
| static_assert( |
| !std::is_copy_assignable< |
| fit::internal::variant<fit::internal::monostate, no_copy>>::value, |
| ""); |
| static_assert( |
| std::is_copy_assignable< |
| fit::internal::variant<fit::internal::monostate, no_move>>::value, |
| ""); |
| static_assert( |
| !std::is_copy_assignable< |
| fit::internal::variant<fit::internal::monostate, no_copy_no_move>>::value, |
| ""); |
| static_assert( |
| std::is_copy_assignable< |
| literal_traits::variant>::value, |
| ""); |
| static_assert( |
| std::is_copy_assignable< |
| complex_traits::variant>::value, |
| ""); |
| } // namespace copy_assignment_test |
| |
| // Ensure the variant is move-constructible only when the types are movable. |
| // Note that copy-constructible types are also considered movable. |
| namespace move_construction_test { |
| static_assert( |
| std::is_move_constructible< |
| fit::internal::variant<fit::internal::monostate>>::value, |
| ""); |
| static_assert( |
| std::is_move_constructible< |
| fit::internal::variant<fit::internal::monostate, no_copy>>::value, |
| ""); |
| static_assert( |
| std::is_move_constructible< |
| fit::internal::variant<fit::internal::monostate, no_move>>::value, |
| ""); |
| static_assert( |
| !std::is_move_constructible< |
| fit::internal::variant<fit::internal::monostate, no_copy_no_move>>::value, |
| ""); |
| static_assert( |
| std::is_move_constructible< |
| literal_traits::variant>::value, |
| ""); |
| static_assert( |
| std::is_move_constructible< |
| complex_traits::variant>::value, |
| ""); |
| } // namespace move_construction_test |
| |
| // Ensure the variant is move-assignable only when the types are movable. |
| // Note that copy-assignable types are also considered movable. |
| namespace move_assignment_test { |
| static_assert( |
| std::is_move_assignable< |
| fit::internal::variant<fit::internal::monostate>>::value, |
| ""); |
| static_assert( |
| std::is_move_assignable< |
| fit::internal::variant<fit::internal::monostate, no_copy>>::value, |
| ""); |
| static_assert( |
| std::is_move_assignable< |
| fit::internal::variant<fit::internal::monostate, no_move>>::value, |
| ""); |
| static_assert( |
| !std::is_move_assignable< |
| fit::internal::variant<fit::internal::monostate, no_copy_no_move>>::value, |
| ""); |
| static_assert( |
| std::is_move_assignable< |
| literal_traits::variant>::value, |
| ""); |
| static_assert( |
| std::is_move_assignable< |
| complex_traits::variant>::value, |
| ""); |
| } // namespace move_assignment_test |
| |
| // Ensure that the correct sequence of base types are considered in the |
| // implementation of variant to ensure that the right methods participate |
| // in overload resolution. |
| namespace impl_test { |
| |
| // Type with a trivial destructor, move, and copy. |
| namespace trivial_type { |
| static_assert( |
| std::is_base_of< |
| fit::internal::variant_base_impl_trivial<fit::internal::monostate, int>, |
| fit::internal::variant<fit::internal::monostate, int>>::value, |
| ""); |
| static_assert( |
| !std::is_base_of< |
| fit::internal::variant_move_impl_non_trivial<fit::internal::monostate, int>, |
| fit::internal::variant<fit::internal::monostate, int>>::value, |
| ""); |
| static_assert( |
| !std::is_base_of< |
| fit::internal::variant_copy_impl_non_trivial<fit::internal::monostate, int>, |
| fit::internal::variant<fit::internal::monostate, int>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_destructible< |
| fit::internal::variant<fit::internal::monostate, int>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_move_constructible< |
| fit::internal::variant<fit::internal::monostate, int>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_copy_constructible< |
| fit::internal::variant<fit::internal::monostate, int>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_move_assignable< |
| fit::internal::variant<fit::internal::monostate, int>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_copy_assignable< |
| fit::internal::variant<fit::internal::monostate, int>>::value, |
| ""); |
| } // namespace trivial_type |
| |
| // Type with a non-trivial destructor implies it has non-trivial move and copy too. |
| namespace non_trivial_destructor_type { |
| static_assert( |
| std::is_base_of< |
| fit::internal::variant_base_impl_non_trivial<fit::internal::monostate, non_trivial_destructor>, |
| fit::internal::variant<fit::internal::monostate, non_trivial_destructor>>::value, |
| ""); |
| static_assert( |
| std::is_base_of< |
| fit::internal::variant_move_impl_non_trivial<fit::internal::monostate, non_trivial_destructor>, |
| fit::internal::variant<fit::internal::monostate, non_trivial_destructor>>::value, |
| ""); |
| static_assert( |
| std::is_base_of< |
| fit::internal::variant_copy_impl_non_trivial<fit::internal::monostate, non_trivial_destructor>, |
| fit::internal::variant<fit::internal::monostate, non_trivial_destructor>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_destructible< |
| fit::internal::variant<fit::internal::monostate, non_trivial_destructor>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_move_constructible< |
| fit::internal::variant<fit::internal::monostate, non_trivial_destructor>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_copy_constructible< |
| fit::internal::variant<fit::internal::monostate, non_trivial_destructor>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_move_assignable< |
| fit::internal::variant<fit::internal::monostate, non_trivial_destructor>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_copy_assignable< |
| fit::internal::variant<fit::internal::monostate, non_trivial_destructor>>::value, |
| ""); |
| } // namespace non_trivial_destructor_type |
| |
| // Type with a non-trivial move constructor actually ends up being trivially |
| // movable anyhow if it has a trivial copy constructor and destructor. |
| namespace non_trivial_move_type { |
| static_assert( |
| std::is_base_of< |
| fit::internal::variant_base_impl_trivial<fit::internal::monostate, non_trivial_move>, |
| fit::internal::variant<fit::internal::monostate, non_trivial_move>>::value, |
| ""); |
| static_assert( |
| !std::is_base_of< |
| fit::internal::variant_move_impl_non_trivial<fit::internal::monostate, non_trivial_move>, |
| fit::internal::variant<fit::internal::monostate, non_trivial_move>>::value, |
| ""); |
| static_assert( |
| !std::is_base_of< |
| fit::internal::variant_copy_impl_non_trivial<fit::internal::monostate, non_trivial_move>, |
| fit::internal::variant<fit::internal::monostate, non_trivial_move>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_destructible< |
| fit::internal::variant<fit::internal::monostate, non_trivial_move>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_move_constructible< |
| fit::internal::variant<fit::internal::monostate, non_trivial_move>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_copy_constructible< |
| fit::internal::variant<fit::internal::monostate, non_trivial_move>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_move_assignable< |
| fit::internal::variant<fit::internal::monostate, non_trivial_move>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_copy_assignable< |
| fit::internal::variant<fit::internal::monostate, non_trivial_move>>::value, |
| ""); |
| } // namespace non_trivial_move_type |
| |
| // Type with a non-trivial copy constructor may be trivially movable while not |
| // trivially copyable. |
| namespace non_trivial_copy_type { |
| static_assert( |
| std::is_base_of< |
| fit::internal::variant_base_impl_trivial<fit::internal::monostate, non_trivial_copy>, |
| fit::internal::variant<fit::internal::monostate, non_trivial_copy>>::value, |
| ""); |
| static_assert( |
| !std::is_base_of< |
| fit::internal::variant_move_impl_non_trivial<fit::internal::monostate, non_trivial_copy>, |
| fit::internal::variant<fit::internal::monostate, non_trivial_copy>>::value, |
| ""); |
| static_assert( |
| std::is_base_of< |
| fit::internal::variant_copy_impl_non_trivial<fit::internal::monostate, non_trivial_copy>, |
| fit::internal::variant<fit::internal::monostate, non_trivial_copy>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_destructible< |
| fit::internal::variant<fit::internal::monostate, non_trivial_copy>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_move_constructible< |
| fit::internal::variant<fit::internal::monostate, non_trivial_copy>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_copy_constructible< |
| fit::internal::variant<fit::internal::monostate, non_trivial_copy>>::value, |
| ""); |
| static_assert( |
| std::is_trivially_move_assignable< |
| fit::internal::variant<fit::internal::monostate, non_trivial_copy>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_copy_assignable< |
| fit::internal::variant<fit::internal::monostate, non_trivial_copy>>::value, |
| ""); |
| } // namespace non_trivial_copy_type |
| |
| // std::string is not trivally destructible, movable, or copyable. |
| namespace string_type { |
| static_assert( |
| std::is_base_of< |
| fit::internal::variant_base_impl_non_trivial<fit::internal::monostate, std::string>, |
| fit::internal::variant<fit::internal::monostate, std::string>>::value, |
| ""); |
| static_assert( |
| std::is_base_of< |
| fit::internal::variant_move_impl_non_trivial<fit::internal::monostate, std::string>, |
| fit::internal::variant<fit::internal::monostate, std::string>>::value, |
| ""); |
| static_assert( |
| std::is_base_of< |
| fit::internal::variant_copy_impl_non_trivial<fit::internal::monostate, std::string>, |
| fit::internal::variant<fit::internal::monostate, std::string>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_destructible< |
| fit::internal::variant<fit::internal::monostate, std::string>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_move_constructible< |
| fit::internal::variant<fit::internal::monostate, std::string>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_copy_constructible< |
| fit::internal::variant<fit::internal::monostate, std::string>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_move_assignable< |
| fit::internal::variant<fit::internal::monostate, std::string>>::value, |
| ""); |
| static_assert( |
| !std::is_trivially_copy_assignable< |
| fit::internal::variant<fit::internal::monostate, std::string>>::value, |
| ""); |
| } // namespace string_type |
| } // namespace impl_test |
| |
| } // namespace |
| |
| BEGIN_TEST_CASE(variant_tests) |
| RUN_TEST(accessors<literal_traits>) |
| RUN_TEST(accessors<complex_traits>) |
| RUN_TEST(copy_move_assign<literal_traits>) |
| RUN_TEST(copy_move_assign<complex_traits>) |
| RUN_TEST(swapping<literal_traits>) |
| RUN_TEST(swapping<complex_traits>) |
| END_TEST_CASE(variant_tests) |