1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // UNSUPPORTED: c++98, c++03, c++11 11 // <optional> 12 13 // optional<T>& operator=(const optional<T>& rhs); 14 15 #include <experimental/optional> 16 #include <type_traits> 17 #include <cassert> 18 19 #include "test_macros.h" 20 21 using std::experimental::optional; 22 23 struct AllowConstAssign { AllowConstAssignAllowConstAssign24 AllowConstAssign(AllowConstAssign const&) {} operator =AllowConstAssign25 AllowConstAssign const& operator=(AllowConstAssign const&) const { 26 return *this; 27 } 28 }; 29 30 struct X 31 { 32 static bool throw_now; 33 34 X() = default; XX35 X(const X&) 36 { 37 if (throw_now) 38 TEST_THROW(6); 39 } 40 }; 41 42 bool X::throw_now = false; 43 main()44int main() 45 { 46 { 47 optional<int> opt; 48 constexpr optional<int> opt2; 49 opt = opt2; 50 static_assert(static_cast<bool>(opt2) == false, ""); 51 assert(static_cast<bool>(opt) == static_cast<bool>(opt2)); 52 } 53 { 54 optional<const AllowConstAssign> opt; 55 optional<const AllowConstAssign> opt2; 56 opt = opt2; 57 } 58 { 59 optional<int> opt; 60 constexpr optional<int> opt2(2); 61 opt = opt2; 62 static_assert(static_cast<bool>(opt2) == true, ""); 63 static_assert(*opt2 == 2, ""); 64 assert(static_cast<bool>(opt) == static_cast<bool>(opt2)); 65 assert(*opt == *opt2); 66 } 67 { 68 optional<int> opt(3); 69 constexpr optional<int> opt2; 70 opt = opt2; 71 static_assert(static_cast<bool>(opt2) == false, ""); 72 assert(static_cast<bool>(opt) == static_cast<bool>(opt2)); 73 } 74 { 75 optional<int> opt(3); 76 constexpr optional<int> opt2(2); 77 opt = opt2; 78 static_assert(static_cast<bool>(opt2) == true, ""); 79 static_assert(*opt2 == 2, ""); 80 assert(static_cast<bool>(opt) == static_cast<bool>(opt2)); 81 assert(*opt == *opt2); 82 } 83 #ifndef TEST_HAS_NO_EXCEPTIONS 84 { 85 optional<X> opt; 86 optional<X> opt2(X{}); 87 assert(static_cast<bool>(opt2) == true); 88 try 89 { 90 X::throw_now = true; 91 opt = opt2; 92 assert(false); 93 } 94 catch (int i) 95 { 96 assert(i == 6); 97 assert(static_cast<bool>(opt) == false); 98 } 99 } 100 #endif 101 } 102