1/*
2    tests/test_stl.cpp -- STL type casters
3
4    Copyright (c) 2017 Wenzel Jakob <wenzel.jakob@epfl.ch>
5
6    All rights reserved. Use of this source code is governed by a
7    BSD-style license that can be found in the LICENSE file.
8*/
9
10#include "pybind11_tests.h"
11#include "constructor_stats.h"
12#include <pybind11/stl.h>
13
14#include <vector>
15#include <string>
16
17// Test with `std::variant` in C++17 mode, or with `boost::variant` in C++11/14
18#if PYBIND11_HAS_VARIANT
19using std::variant;
20#elif defined(PYBIND11_TEST_BOOST) && (!defined(_MSC_VER) || _MSC_VER >= 1910)
21#  include <boost/variant.hpp>
22#  define PYBIND11_HAS_VARIANT 1
23using boost::variant;
24
25namespace pybind11 { namespace detail {
26template <typename... Ts>
27struct type_caster<boost::variant<Ts...>> : variant_caster<boost::variant<Ts...>> {};
28
29template <>
30struct visit_helper<boost::variant> {
31    template <typename... Args>
32    static auto call(Args &&...args) -> decltype(boost::apply_visitor(args...)) {
33        return boost::apply_visitor(args...);
34    }
35};
36}} // namespace pybind11::detail
37#endif
38
39PYBIND11_MAKE_OPAQUE(std::vector<std::string, std::allocator<std::string>>);
40
41/// Issue #528: templated constructor
42struct TplCtorClass {
43    template <typename T> TplCtorClass(const T &) { }
44    bool operator==(const TplCtorClass &) const { return true; }
45};
46
47namespace std {
48    template <>
49    struct hash<TplCtorClass> { size_t operator()(const TplCtorClass &) const { return 0; } };
50}
51
52
53TEST_SUBMODULE(stl, m) {
54    // test_vector
55    m.def("cast_vector", []() { return std::vector<int>{1}; });
56    m.def("load_vector", [](const std::vector<int> &v) { return v.at(0) == 1 && v.at(1) == 2; });
57    // `std::vector<bool>` is special because it returns proxy objects instead of references
58    m.def("cast_bool_vector", []() { return std::vector<bool>{true, false}; });
59    m.def("load_bool_vector", [](const std::vector<bool> &v) {
60        return v.at(0) == true && v.at(1) == false;
61    });
62    // Unnumbered regression (caused by #936): pointers to stl containers aren't castable
63    static std::vector<RValueCaster> lvv{2};
64    m.def("cast_ptr_vector", []() { return &lvv; });
65
66    // test_deque
67    m.def("cast_deque", []() { return std::deque<int>{1}; });
68    m.def("load_deque", [](const std::deque<int> &v) { return v.at(0) == 1 && v.at(1) == 2; });
69
70    // test_array
71    m.def("cast_array", []() { return std::array<int, 2> {{1 , 2}}; });
72    m.def("load_array", [](const std::array<int, 2> &a) { return a[0] == 1 && a[1] == 2; });
73
74    // test_valarray
75    m.def("cast_valarray", []() { return std::valarray<int>{1, 4, 9}; });
76    m.def("load_valarray", [](const std::valarray<int>& v) {
77        return v.size() == 3 && v[0] == 1 && v[1] == 4 && v[2] == 9;
78    });
79
80    // test_map
81    m.def("cast_map", []() { return std::map<std::string, std::string>{{"key", "value"}}; });
82    m.def("load_map", [](const std::map<std::string, std::string> &map) {
83        return map.at("key") == "value" && map.at("key2") == "value2";
84    });
85
86    // test_set
87    m.def("cast_set", []() { return std::set<std::string>{"key1", "key2"}; });
88    m.def("load_set", [](const std::set<std::string> &set) {
89        return set.count("key1") && set.count("key2") && set.count("key3");
90    });
91
92    // test_recursive_casting
93    m.def("cast_rv_vector", []() { return std::vector<RValueCaster>{2}; });
94    m.def("cast_rv_array", []() { return std::array<RValueCaster, 3>(); });
95    // NB: map and set keys are `const`, so while we technically do move them (as `const Type &&`),
96    // casters don't typically do anything with that, which means they fall to the `const Type &`
97    // caster.
98    m.def("cast_rv_map", []() { return std::unordered_map<std::string, RValueCaster>{{"a", RValueCaster{}}}; });
99    m.def("cast_rv_nested", []() {
100        std::vector<std::array<std::list<std::unordered_map<std::string, RValueCaster>>, 2>> v;
101        v.emplace_back(); // add an array
102        v.back()[0].emplace_back(); // add a map to the array
103        v.back()[0].back().emplace("b", RValueCaster{});
104        v.back()[0].back().emplace("c", RValueCaster{});
105        v.back()[1].emplace_back(); // add a map to the array
106        v.back()[1].back().emplace("a", RValueCaster{});
107        return v;
108    });
109    static std::array<RValueCaster, 2> lva;
110    static std::unordered_map<std::string, RValueCaster> lvm{{"a", RValueCaster{}}, {"b", RValueCaster{}}};
111    static std::unordered_map<std::string, std::vector<std::list<std::array<RValueCaster, 2>>>> lvn;
112    lvn["a"].emplace_back(); // add a list
113    lvn["a"].back().emplace_back(); // add an array
114    lvn["a"].emplace_back(); // another list
115    lvn["a"].back().emplace_back(); // add an array
116    lvn["b"].emplace_back(); // add a list
117    lvn["b"].back().emplace_back(); // add an array
118    lvn["b"].back().emplace_back(); // add another array
119    m.def("cast_lv_vector", []() -> const decltype(lvv) & { return lvv; });
120    m.def("cast_lv_array", []() -> const decltype(lva) & { return lva; });
121    m.def("cast_lv_map", []() -> const decltype(lvm) & { return lvm; });
122    m.def("cast_lv_nested", []() -> const decltype(lvn) & { return lvn; });
123    // #853:
124    m.def("cast_unique_ptr_vector", []() {
125        std::vector<std::unique_ptr<UserType>> v;
126        v.emplace_back(new UserType{7});
127        v.emplace_back(new UserType{42});
128        return v;
129    });
130
131    // test_move_out_container
132    struct MoveOutContainer {
133        struct Value { int value; };
134        std::list<Value> move_list() const { return {{0}, {1}, {2}}; }
135    };
136    py::class_<MoveOutContainer::Value>(m, "MoveOutContainerValue")
137        .def_readonly("value", &MoveOutContainer::Value::value);
138    py::class_<MoveOutContainer>(m, "MoveOutContainer")
139        .def(py::init<>())
140        .def_property_readonly("move_list", &MoveOutContainer::move_list);
141
142    // Class that can be move- and copy-constructed, but not assigned
143    struct NoAssign {
144        int value;
145
146        explicit NoAssign(int value = 0) : value(value) { }
147        NoAssign(const NoAssign &) = default;
148        NoAssign(NoAssign &&) = default;
149
150        NoAssign &operator=(const NoAssign &) = delete;
151        NoAssign &operator=(NoAssign &&) = delete;
152    };
153    py::class_<NoAssign>(m, "NoAssign", "Class with no C++ assignment operators")
154        .def(py::init<>())
155        .def(py::init<int>());
156
157#ifdef PYBIND11_HAS_OPTIONAL
158    // test_optional
159    m.attr("has_optional") = true;
160
161    using opt_int = std::optional<int>;
162    using opt_no_assign = std::optional<NoAssign>;
163    m.def("double_or_zero", [](const opt_int& x) -> int {
164        return x.value_or(0) * 2;
165    });
166    m.def("half_or_none", [](int x) -> opt_int {
167        return x ? opt_int(x / 2) : opt_int();
168    });
169    m.def("test_nullopt", [](opt_int x) {
170        return x.value_or(42);
171    }, py::arg_v("x", std::nullopt, "None"));
172    m.def("test_no_assign", [](const opt_no_assign &x) {
173        return x ? x->value : 42;
174    }, py::arg_v("x", std::nullopt, "None"));
175
176    m.def("nodefer_none_optional", [](std::optional<int>) { return true; });
177    m.def("nodefer_none_optional", [](py::none) { return false; });
178#endif
179
180#ifdef PYBIND11_HAS_EXP_OPTIONAL
181    // test_exp_optional
182    m.attr("has_exp_optional") = true;
183
184    using exp_opt_int = std::experimental::optional<int>;
185    using exp_opt_no_assign = std::experimental::optional<NoAssign>;
186    m.def("double_or_zero_exp", [](const exp_opt_int& x) -> int {
187        return x.value_or(0) * 2;
188    });
189    m.def("half_or_none_exp", [](int x) -> exp_opt_int {
190        return x ? exp_opt_int(x / 2) : exp_opt_int();
191    });
192    m.def("test_nullopt_exp", [](exp_opt_int x) {
193        return x.value_or(42);
194    }, py::arg_v("x", std::experimental::nullopt, "None"));
195    m.def("test_no_assign_exp", [](const exp_opt_no_assign &x) {
196        return x ? x->value : 42;
197    }, py::arg_v("x", std::experimental::nullopt, "None"));
198#endif
199
200#ifdef PYBIND11_HAS_VARIANT
201    static_assert(std::is_same<py::detail::variant_caster_visitor::result_type, py::handle>::value,
202                  "visitor::result_type is required by boost::variant in C++11 mode");
203
204    struct visitor {
205        using result_type = const char *;
206
207        result_type operator()(int) { return "int"; }
208        result_type operator()(std::string) { return "std::string"; }
209        result_type operator()(double) { return "double"; }
210        result_type operator()(std::nullptr_t) { return "std::nullptr_t"; }
211    };
212
213    // test_variant
214    m.def("load_variant", [](variant<int, std::string, double, std::nullptr_t> v) {
215        return py::detail::visit_helper<variant>::call(visitor(), v);
216    });
217    m.def("load_variant_2pass", [](variant<double, int> v) {
218        return py::detail::visit_helper<variant>::call(visitor(), v);
219    });
220    m.def("cast_variant", []() {
221        using V = variant<int, std::string>;
222        return py::make_tuple(V(5), V("Hello"));
223    });
224#endif
225
226    // #528: templated constructor
227    // (no python tests: the test here is that this compiles)
228    m.def("tpl_ctor_vector", [](std::vector<TplCtorClass> &) {});
229    m.def("tpl_ctor_map", [](std::unordered_map<TplCtorClass, TplCtorClass> &) {});
230    m.def("tpl_ctor_set", [](std::unordered_set<TplCtorClass> &) {});
231#if defined(PYBIND11_HAS_OPTIONAL)
232    m.def("tpl_constr_optional", [](std::optional<TplCtorClass> &) {});
233#elif defined(PYBIND11_HAS_EXP_OPTIONAL)
234    m.def("tpl_constr_optional", [](std::experimental::optional<TplCtorClass> &) {});
235#endif
236
237    // test_vec_of_reference_wrapper
238    // #171: Can't return STL structures containing reference wrapper
239    m.def("return_vec_of_reference_wrapper", [](std::reference_wrapper<UserType> p4) {
240        static UserType p1{1}, p2{2}, p3{3};
241        return std::vector<std::reference_wrapper<UserType>> {
242            std::ref(p1), std::ref(p2), std::ref(p3), p4
243        };
244    });
245
246    // test_stl_pass_by_pointer
247    m.def("stl_pass_by_pointer", [](std::vector<int>* v) { return *v; }, "v"_a=nullptr);
248
249    // #1258: pybind11/stl.h converts string to vector<string>
250    m.def("func_with_string_or_vector_string_arg_overload", [](std::vector<std::string>) { return 1; });
251    m.def("func_with_string_or_vector_string_arg_overload", [](std::list<std::string>) { return 2; });
252    m.def("func_with_string_or_vector_string_arg_overload", [](std::string) { return 3; });
253
254    class Placeholder {
255    public:
256        Placeholder() { print_created(this); }
257        Placeholder(const Placeholder &) = delete;
258        ~Placeholder() { print_destroyed(this); }
259    };
260    py::class_<Placeholder>(m, "Placeholder");
261
262    /// test_stl_vector_ownership
263    m.def("test_stl_ownership",
264          []() {
265              std::vector<Placeholder *> result;
266              result.push_back(new Placeholder());
267              return result;
268          },
269          py::return_value_policy::take_ownership);
270
271    m.def("array_cast_sequence", [](std::array<int, 3> x) { return x; });
272
273    /// test_issue_1561
274    struct Issue1561Inner { std::string data; };
275    struct Issue1561Outer { std::vector<Issue1561Inner> list; };
276
277    py::class_<Issue1561Inner>(m, "Issue1561Inner")
278        .def(py::init<std::string>())
279        .def_readwrite("data", &Issue1561Inner::data);
280
281    py::class_<Issue1561Outer>(m, "Issue1561Outer")
282        .def(py::init<>())
283        .def_readwrite("list", &Issue1561Outer::list);
284}
285