1 // Copyright Louis Dionne 2013-2017
2 // Distributed under the Boost Software License, Version 1.0.
3 // (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
5 #ifndef TEST_SUPPORT_TRACKED_HPP
6 #define TEST_SUPPORT_TRACKED_HPP
8 // Define this if you want Tracked objects to print information to stderr.
9 // #define TRACKED_PRINT_STUFF
11 #include <boost/hana/assert.hpp>
13 #ifdef TRACKED_PRINT_STUFF
21 enum class State { CONSTRUCTED, MOVED_FROM, DESTROYED };
26 explicit Tracked(int k) : value{k}, state{State::CONSTRUCTED} {
27 #ifdef TRACKED_PRINT_STUFF
28 std::cerr << "constructing " << *this << '\n';
32 Tracked(Tracked const& t) : value{t.value}, state{State::CONSTRUCTED} {
33 BOOST_HANA_RUNTIME_CHECK(t.state != State::MOVED_FROM &&
34 "copying a moved-from object");
36 BOOST_HANA_RUNTIME_CHECK(t.state != State::DESTROYED &&
37 "copying a destroyed object");
39 #ifdef TRACKED_PRINT_STUFF
40 std::cerr << "copying " << *this << '\n';
44 Tracked(Tracked&& t) : value{t.value}, state{State::CONSTRUCTED} {
45 BOOST_HANA_RUNTIME_CHECK(t.state != State::MOVED_FROM &&
46 "double moving from an object");
48 BOOST_HANA_RUNTIME_CHECK(t.state != State::DESTROYED &&
49 "moving from a destroyed object");
51 #ifdef TRACKED_PRINT_STUFF
52 std::cerr << "moving " << t << '\n';
54 t.state = State::MOVED_FROM;
57 Tracked& operator=(Tracked const& other) {
58 BOOST_HANA_RUNTIME_CHECK(this->state != State::DESTROYED &&
59 "assigning to a destroyed object");
61 BOOST_HANA_RUNTIME_CHECK(other.state != State::MOVED_FROM &&
62 "assigning a moved-from object");
64 BOOST_HANA_RUNTIME_CHECK(other.state != State::DESTROYED &&
65 "assigning a destroyed object");
67 #ifdef TRACKED_PRINT_STUFF
68 std::cerr << "assigning " << other << " to " << *this << '\n';
70 this->value = other.value;
74 Tracked& operator=(Tracked&& other) {
75 BOOST_HANA_RUNTIME_CHECK(this->state != State::DESTROYED &&
76 "assigning to a destroyed object");
78 BOOST_HANA_RUNTIME_CHECK(other.state != State::MOVED_FROM &&
79 "double-moving from an object");
81 BOOST_HANA_RUNTIME_CHECK(other.state != State::DESTROYED &&
82 "assigning a destroyed object");
84 #ifdef TRACKED_PRINT_STUFF
85 std::cerr << "assigning " << other << " to " << *this << '\n';
87 this->value = other.value;
88 other.state = State::MOVED_FROM;
93 BOOST_HANA_RUNTIME_CHECK(state != State::DESTROYED &&
94 "double-destroying an object");
96 #ifdef TRACKED_PRINT_STUFF
97 std::cerr << "destructing " << *this << '\n';
99 state = State::DESTROYED;
102 template <typename CharT, typename Traits>
103 friend std::basic_ostream<CharT, Traits>&
104 operator<<(std::basic_ostream<CharT, Traits>& os, Tracked const& t) {
105 os << "Tracked{" << t.value << "}";
107 case State::CONSTRUCTED:
109 case State::MOVED_FROM:
110 os << "[moved from]"; break;
111 case State::DESTROYED:
112 os << "[destroyed]"; break;
114 BOOST_HANA_RUNTIME_CHECK(false && "never reached");
120 #endif // !TEST_SUPPORT_TRACKED_HPP