1/*
2    tests/test_methods_and_attributes.cpp -- constructors, deconstructors, attribute access,
3    __str__, argument and return value conventions
4
5    Copyright (c) 2016 Wenzel Jakob <wenzel.jakob@epfl.ch>
6
7    All rights reserved. Use of this source code is governed by a
8    BSD-style license that can be found in the LICENSE file.
9*/
10
11#include "pybind11_tests.h"
12#include "constructor_stats.h"
13
14#if !defined(PYBIND11_OVERLOAD_CAST)
15template <typename... Args>
16using overload_cast_ = pybind11::detail::overload_cast_impl<Args...>;
17#endif
18
19class ExampleMandA {
20public:
21    ExampleMandA() { print_default_created(this); }
22    ExampleMandA(int value) : value(value) { print_created(this, value); }
23    ExampleMandA(const ExampleMandA &e) : value(e.value) { print_copy_created(this); }
24    ExampleMandA(ExampleMandA &&e) : value(e.value) { print_move_created(this); }
25    ~ExampleMandA() { print_destroyed(this); }
26
27    std::string toString() {
28        return "ExampleMandA[value=" + std::to_string(value) + "]";
29    }
30
31    void operator=(const ExampleMandA &e) { print_copy_assigned(this); value = e.value; }
32    void operator=(ExampleMandA &&e) { print_move_assigned(this); value = e.value; }
33
34    void add1(ExampleMandA other) { value += other.value; }         // passing by value
35    void add2(ExampleMandA &other) { value += other.value; }        // passing by reference
36    void add3(const ExampleMandA &other) { value += other.value; }  // passing by const reference
37    void add4(ExampleMandA *other) { value += other->value; }       // passing by pointer
38    void add5(const ExampleMandA *other) { value += other->value; } // passing by const pointer
39
40    void add6(int other) { value += other; }                        // passing by value
41    void add7(int &other) { value += other; }                       // passing by reference
42    void add8(const int &other) { value += other; }                 // passing by const reference
43    void add9(int *other) { value += *other; }                      // passing by pointer
44    void add10(const int *other) { value += *other; }               // passing by const pointer
45
46    ExampleMandA self1() { return *this; }                          // return by value
47    ExampleMandA &self2() { return *this; }                         // return by reference
48    const ExampleMandA &self3() { return *this; }                   // return by const reference
49    ExampleMandA *self4() { return this; }                          // return by pointer
50    const ExampleMandA *self5() { return this; }                    // return by const pointer
51
52    int internal1() { return value; }                               // return by value
53    int &internal2() { return value; }                              // return by reference
54    const int &internal3() { return value; }                        // return by const reference
55    int *internal4() { return &value; }                             // return by pointer
56    const int *internal5() { return &value; }                       // return by const pointer
57
58    py::str overloaded()             { return "()"; }
59    py::str overloaded(int)          { return "(int)"; }
60    py::str overloaded(int, float)   { return "(int, float)"; }
61    py::str overloaded(float, int)   { return "(float, int)"; }
62    py::str overloaded(int, int)     { return "(int, int)"; }
63    py::str overloaded(float, float) { return "(float, float)"; }
64    py::str overloaded(int)          const { return "(int) const"; }
65    py::str overloaded(int, float)   const { return "(int, float) const"; }
66    py::str overloaded(float, int)   const { return "(float, int) const"; }
67    py::str overloaded(int, int)     const { return "(int, int) const"; }
68    py::str overloaded(float, float) const { return "(float, float) const"; }
69
70    static py::str overloaded(float) { return "static float"; }
71
72    int value = 0;
73};
74
75struct TestProperties {
76    int value = 1;
77    static int static_value;
78
79    int get() const { return value; }
80    void set(int v) { value = v; }
81
82    static int static_get() { return static_value; }
83    static void static_set(int v) { static_value = v; }
84};
85int TestProperties::static_value = 1;
86
87struct TestPropertiesOverride : TestProperties {
88    int value = 99;
89    static int static_value;
90};
91int TestPropertiesOverride::static_value = 99;
92
93struct TestPropRVP {
94    UserType v1{1};
95    UserType v2{1};
96    static UserType sv1;
97    static UserType sv2;
98
99    const UserType &get1() const { return v1; }
100    const UserType &get2() const { return v2; }
101    UserType get_rvalue() const { return v2; }
102    void set1(int v) { v1.set(v); }
103    void set2(int v) { v2.set(v); }
104};
105UserType TestPropRVP::sv1(1);
106UserType TestPropRVP::sv2(1);
107
108// py::arg/py::arg_v testing: these arguments just record their argument when invoked
109class ArgInspector1 { public: std::string arg = "(default arg inspector 1)"; };
110class ArgInspector2 { public: std::string arg = "(default arg inspector 2)"; };
111class ArgAlwaysConverts { };
112namespace pybind11 { namespace detail {
113template <> struct type_caster<ArgInspector1> {
114public:
115    PYBIND11_TYPE_CASTER(ArgInspector1, _("ArgInspector1"));
116
117    bool load(handle src, bool convert) {
118        value.arg = "loading ArgInspector1 argument " +
119            std::string(convert ? "WITH" : "WITHOUT") + " conversion allowed.  "
120            "Argument value = " + (std::string) str(src);
121        return true;
122    }
123
124    static handle cast(const ArgInspector1 &src, return_value_policy, handle) {
125        return str(src.arg).release();
126    }
127};
128template <> struct type_caster<ArgInspector2> {
129public:
130    PYBIND11_TYPE_CASTER(ArgInspector2, _("ArgInspector2"));
131
132    bool load(handle src, bool convert) {
133        value.arg = "loading ArgInspector2 argument " +
134            std::string(convert ? "WITH" : "WITHOUT") + " conversion allowed.  "
135            "Argument value = " + (std::string) str(src);
136        return true;
137    }
138
139    static handle cast(const ArgInspector2 &src, return_value_policy, handle) {
140        return str(src.arg).release();
141    }
142};
143template <> struct type_caster<ArgAlwaysConverts> {
144public:
145    PYBIND11_TYPE_CASTER(ArgAlwaysConverts, _("ArgAlwaysConverts"));
146
147    bool load(handle, bool convert) {
148        return convert;
149    }
150
151    static handle cast(const ArgAlwaysConverts &, return_value_policy, handle) {
152        return py::none().release();
153    }
154};
155}}
156
157// test_custom_caster_destruction
158class DestructionTester {
159public:
160    DestructionTester() { print_default_created(this); }
161    ~DestructionTester() { print_destroyed(this); }
162    DestructionTester(const DestructionTester &) { print_copy_created(this); }
163    DestructionTester(DestructionTester &&) { print_move_created(this); }
164    DestructionTester &operator=(const DestructionTester &) { print_copy_assigned(this); return *this; }
165    DestructionTester &operator=(DestructionTester &&) { print_move_assigned(this); return *this; }
166};
167namespace pybind11 { namespace detail {
168template <> struct type_caster<DestructionTester> {
169    PYBIND11_TYPE_CASTER(DestructionTester, _("DestructionTester"));
170    bool load(handle, bool) { return true; }
171
172    static handle cast(const DestructionTester &, return_value_policy, handle) {
173        return py::bool_(true).release();
174    }
175};
176}}
177
178// Test None-allowed py::arg argument policy
179class NoneTester { public: int answer = 42; };
180int none1(const NoneTester &obj) { return obj.answer; }
181int none2(NoneTester *obj) { return obj ? obj->answer : -1; }
182int none3(std::shared_ptr<NoneTester> &obj) { return obj ? obj->answer : -1; }
183int none4(std::shared_ptr<NoneTester> *obj) { return obj && *obj ? (*obj)->answer : -1; }
184int none5(std::shared_ptr<NoneTester> obj) { return obj ? obj->answer : -1; }
185
186struct StrIssue {
187    int val = -1;
188
189    StrIssue() = default;
190    StrIssue(int i) : val{i} {}
191};
192
193// Issues #854, #910: incompatible function args when member function/pointer is in unregistered base class
194class UnregisteredBase {
195public:
196    void do_nothing() const {}
197    void increase_value() { rw_value++; ro_value += 0.25; }
198    void set_int(int v) { rw_value = v; }
199    int get_int() const { return rw_value; }
200    double get_double() const { return ro_value; }
201    int rw_value = 42;
202    double ro_value = 1.25;
203};
204class RegisteredDerived : public UnregisteredBase {
205public:
206    using UnregisteredBase::UnregisteredBase;
207    double sum() const { return rw_value + ro_value; }
208};
209
210TEST_SUBMODULE(methods_and_attributes, m) {
211    // test_methods_and_attributes
212    py::class_<ExampleMandA> emna(m, "ExampleMandA");
213    emna.def(py::init<>())
214        .def(py::init<int>())
215        .def(py::init<const ExampleMandA&>())
216        .def("add1", &ExampleMandA::add1)
217        .def("add2", &ExampleMandA::add2)
218        .def("add3", &ExampleMandA::add3)
219        .def("add4", &ExampleMandA::add4)
220        .def("add5", &ExampleMandA::add5)
221        .def("add6", &ExampleMandA::add6)
222        .def("add7", &ExampleMandA::add7)
223        .def("add8", &ExampleMandA::add8)
224        .def("add9", &ExampleMandA::add9)
225        .def("add10", &ExampleMandA::add10)
226        .def("self1", &ExampleMandA::self1)
227        .def("self2", &ExampleMandA::self2)
228        .def("self3", &ExampleMandA::self3)
229        .def("self4", &ExampleMandA::self4)
230        .def("self5", &ExampleMandA::self5)
231        .def("internal1", &ExampleMandA::internal1)
232        .def("internal2", &ExampleMandA::internal2)
233        .def("internal3", &ExampleMandA::internal3)
234        .def("internal4", &ExampleMandA::internal4)
235        .def("internal5", &ExampleMandA::internal5)
236#if defined(PYBIND11_OVERLOAD_CAST)
237        .def("overloaded", py::overload_cast<>(&ExampleMandA::overloaded))
238        .def("overloaded", py::overload_cast<int>(&ExampleMandA::overloaded))
239        .def("overloaded", py::overload_cast<int,   float>(&ExampleMandA::overloaded))
240        .def("overloaded", py::overload_cast<float,   int>(&ExampleMandA::overloaded))
241        .def("overloaded", py::overload_cast<int,     int>(&ExampleMandA::overloaded))
242        .def("overloaded", py::overload_cast<float, float>(&ExampleMandA::overloaded))
243        .def("overloaded_float", py::overload_cast<float, float>(&ExampleMandA::overloaded))
244        .def("overloaded_const", py::overload_cast<int         >(&ExampleMandA::overloaded, py::const_))
245        .def("overloaded_const", py::overload_cast<int,   float>(&ExampleMandA::overloaded, py::const_))
246        .def("overloaded_const", py::overload_cast<float,   int>(&ExampleMandA::overloaded, py::const_))
247        .def("overloaded_const", py::overload_cast<int,     int>(&ExampleMandA::overloaded, py::const_))
248        .def("overloaded_const", py::overload_cast<float, float>(&ExampleMandA::overloaded, py::const_))
249#else
250        // Use both the traditional static_cast method and the C++11 compatible overload_cast_
251        .def("overloaded", overload_cast_<>()(&ExampleMandA::overloaded))
252        .def("overloaded", overload_cast_<int>()(&ExampleMandA::overloaded))
253        .def("overloaded", overload_cast_<int,   float>()(&ExampleMandA::overloaded))
254        .def("overloaded", static_cast<py::str (ExampleMandA::*)(float,   int)>(&ExampleMandA::overloaded))
255        .def("overloaded", static_cast<py::str (ExampleMandA::*)(int,     int)>(&ExampleMandA::overloaded))
256        .def("overloaded", static_cast<py::str (ExampleMandA::*)(float, float)>(&ExampleMandA::overloaded))
257        .def("overloaded_float", overload_cast_<float, float>()(&ExampleMandA::overloaded))
258        .def("overloaded_const", overload_cast_<int         >()(&ExampleMandA::overloaded, py::const_))
259        .def("overloaded_const", overload_cast_<int,   float>()(&ExampleMandA::overloaded, py::const_))
260        .def("overloaded_const", static_cast<py::str (ExampleMandA::*)(float,   int) const>(&ExampleMandA::overloaded))
261        .def("overloaded_const", static_cast<py::str (ExampleMandA::*)(int,     int) const>(&ExampleMandA::overloaded))
262        .def("overloaded_const", static_cast<py::str (ExampleMandA::*)(float, float) const>(&ExampleMandA::overloaded))
263#endif
264        // test_no_mixed_overloads
265        // Raise error if trying to mix static/non-static overloads on the same name:
266        .def_static("add_mixed_overloads1", []() {
267            auto emna = py::reinterpret_borrow<py::class_<ExampleMandA>>(py::module::import("pybind11_tests.methods_and_attributes").attr("ExampleMandA"));
268            emna.def       ("overload_mixed1", static_cast<py::str (ExampleMandA::*)(int, int)>(&ExampleMandA::overloaded))
269                .def_static("overload_mixed1", static_cast<py::str (              *)(float   )>(&ExampleMandA::overloaded));
270        })
271        .def_static("add_mixed_overloads2", []() {
272            auto emna = py::reinterpret_borrow<py::class_<ExampleMandA>>(py::module::import("pybind11_tests.methods_and_attributes").attr("ExampleMandA"));
273            emna.def_static("overload_mixed2", static_cast<py::str (              *)(float   )>(&ExampleMandA::overloaded))
274                .def       ("overload_mixed2", static_cast<py::str (ExampleMandA::*)(int, int)>(&ExampleMandA::overloaded));
275        })
276        .def("__str__", &ExampleMandA::toString)
277        .def_readwrite("value", &ExampleMandA::value);
278
279    // test_copy_method
280    // Issue #443: can't call copied methods in Python 3
281    emna.attr("add2b") = emna.attr("add2");
282
283    // test_properties, test_static_properties, test_static_cls
284    py::class_<TestProperties>(m, "TestProperties")
285        .def(py::init<>())
286        .def_readonly("def_readonly", &TestProperties::value)
287        .def_readwrite("def_readwrite", &TestProperties::value)
288        .def_property("def_writeonly", nullptr,
289                      [](TestProperties& s,int v) { s.value = v; } )
290        .def_property("def_property_writeonly", nullptr, &TestProperties::set)
291        .def_property_readonly("def_property_readonly", &TestProperties::get)
292        .def_property("def_property", &TestProperties::get, &TestProperties::set)
293        .def_property("def_property_impossible", nullptr, nullptr)
294        .def_readonly_static("def_readonly_static", &TestProperties::static_value)
295        .def_readwrite_static("def_readwrite_static", &TestProperties::static_value)
296        .def_property_static("def_writeonly_static", nullptr,
297                             [](py::object, int v) { TestProperties::static_value = v; })
298        .def_property_readonly_static("def_property_readonly_static",
299                                      [](py::object) { return TestProperties::static_get(); })
300        .def_property_static("def_property_writeonly_static", nullptr,
301                             [](py::object, int v) { return TestProperties::static_set(v); })
302        .def_property_static("def_property_static",
303                             [](py::object) { return TestProperties::static_get(); },
304                             [](py::object, int v) { TestProperties::static_set(v); })
305        .def_property_static("static_cls",
306                             [](py::object cls) { return cls; },
307                             [](py::object cls, py::function f) { f(cls); });
308
309    py::class_<TestPropertiesOverride, TestProperties>(m, "TestPropertiesOverride")
310        .def(py::init<>())
311        .def_readonly("def_readonly", &TestPropertiesOverride::value)
312        .def_readonly_static("def_readonly_static", &TestPropertiesOverride::static_value);
313
314    auto static_get1 = [](py::object) -> const UserType & { return TestPropRVP::sv1; };
315    auto static_get2 = [](py::object) -> const UserType & { return TestPropRVP::sv2; };
316    auto static_set1 = [](py::object, int v) { TestPropRVP::sv1.set(v); };
317    auto static_set2 = [](py::object, int v) { TestPropRVP::sv2.set(v); };
318    auto rvp_copy = py::return_value_policy::copy;
319
320    // test_property_return_value_policies
321    py::class_<TestPropRVP>(m, "TestPropRVP")
322        .def(py::init<>())
323        .def_property_readonly("ro_ref", &TestPropRVP::get1)
324        .def_property_readonly("ro_copy", &TestPropRVP::get2, rvp_copy)
325        .def_property_readonly("ro_func", py::cpp_function(&TestPropRVP::get2, rvp_copy))
326        .def_property("rw_ref", &TestPropRVP::get1, &TestPropRVP::set1)
327        .def_property("rw_copy", &TestPropRVP::get2, &TestPropRVP::set2, rvp_copy)
328        .def_property("rw_func", py::cpp_function(&TestPropRVP::get2, rvp_copy), &TestPropRVP::set2)
329        .def_property_readonly_static("static_ro_ref", static_get1)
330        .def_property_readonly_static("static_ro_copy", static_get2, rvp_copy)
331        .def_property_readonly_static("static_ro_func", py::cpp_function(static_get2, rvp_copy))
332        .def_property_static("static_rw_ref", static_get1, static_set1)
333        .def_property_static("static_rw_copy", static_get2, static_set2, rvp_copy)
334        .def_property_static("static_rw_func", py::cpp_function(static_get2, rvp_copy), static_set2)
335        // test_property_rvalue_policy
336        .def_property_readonly("rvalue", &TestPropRVP::get_rvalue)
337        .def_property_readonly_static("static_rvalue", [](py::object) { return UserType(1); });
338
339    // test_metaclass_override
340    struct MetaclassOverride { };
341    py::class_<MetaclassOverride>(m, "MetaclassOverride", py::metaclass((PyObject *) &PyType_Type))
342        .def_property_readonly_static("readonly", [](py::object) { return 1; });
343
344#if !defined(PYPY_VERSION)
345    // test_dynamic_attributes
346    class DynamicClass {
347    public:
348        DynamicClass() { print_default_created(this); }
349        ~DynamicClass() { print_destroyed(this); }
350    };
351    py::class_<DynamicClass>(m, "DynamicClass", py::dynamic_attr())
352        .def(py::init());
353
354    class CppDerivedDynamicClass : public DynamicClass { };
355    py::class_<CppDerivedDynamicClass, DynamicClass>(m, "CppDerivedDynamicClass")
356        .def(py::init());
357#endif
358
359    // test_noconvert_args
360    //
361    // Test converting.  The ArgAlwaysConverts is just there to make the first no-conversion pass
362    // fail so that our call always ends up happening via the second dispatch (the one that allows
363    // some conversion).
364    class ArgInspector {
365    public:
366        ArgInspector1 f(ArgInspector1 a, ArgAlwaysConverts) { return a; }
367        std::string g(ArgInspector1 a, const ArgInspector1 &b, int c, ArgInspector2 *d, ArgAlwaysConverts) {
368            return a.arg + "\n" + b.arg + "\n" + std::to_string(c) + "\n" + d->arg;
369        }
370        static ArgInspector2 h(ArgInspector2 a, ArgAlwaysConverts) { return a; }
371    };
372    py::class_<ArgInspector>(m, "ArgInspector")
373        .def(py::init<>())
374        .def("f", &ArgInspector::f, py::arg(), py::arg() = ArgAlwaysConverts())
375        .def("g", &ArgInspector::g, "a"_a.noconvert(), "b"_a, "c"_a.noconvert()=13, "d"_a=ArgInspector2(), py::arg() = ArgAlwaysConverts())
376        .def_static("h", &ArgInspector::h, py::arg().noconvert(), py::arg() = ArgAlwaysConverts())
377        ;
378    m.def("arg_inspect_func", [](ArgInspector2 a, ArgInspector1 b, ArgAlwaysConverts) { return a.arg + "\n" + b.arg; },
379            py::arg().noconvert(false), py::arg_v(nullptr, ArgInspector1()).noconvert(true), py::arg() = ArgAlwaysConverts());
380
381    m.def("floats_preferred", [](double f) { return 0.5 * f; }, py::arg("f"));
382    m.def("floats_only", [](double f) { return 0.5 * f; }, py::arg("f").noconvert());
383    m.def("ints_preferred", [](int i) { return i / 2; }, py::arg("i"));
384    m.def("ints_only", [](int i) { return i / 2; }, py::arg("i").noconvert());
385
386    // test_bad_arg_default
387    // Issue/PR #648: bad arg default debugging output
388#if !defined(NDEBUG)
389    m.attr("debug_enabled") = true;
390#else
391    m.attr("debug_enabled") = false;
392#endif
393    m.def("bad_arg_def_named", []{
394        auto m = py::module::import("pybind11_tests");
395        m.def("should_fail", [](int, UnregisteredType) {}, py::arg(), py::arg("a") = UnregisteredType());
396    });
397    m.def("bad_arg_def_unnamed", []{
398        auto m = py::module::import("pybind11_tests");
399        m.def("should_fail", [](int, UnregisteredType) {}, py::arg(), py::arg() = UnregisteredType());
400    });
401
402    // test_accepts_none
403    py::class_<NoneTester, std::shared_ptr<NoneTester>>(m, "NoneTester")
404        .def(py::init<>());
405    m.def("no_none1", &none1, py::arg().none(false));
406    m.def("no_none2", &none2, py::arg().none(false));
407    m.def("no_none3", &none3, py::arg().none(false));
408    m.def("no_none4", &none4, py::arg().none(false));
409    m.def("no_none5", &none5, py::arg().none(false));
410    m.def("ok_none1", &none1);
411    m.def("ok_none2", &none2, py::arg().none(true));
412    m.def("ok_none3", &none3);
413    m.def("ok_none4", &none4, py::arg().none(true));
414    m.def("ok_none5", &none5);
415
416    // test_str_issue
417    // Issue #283: __str__ called on uninitialized instance when constructor arguments invalid
418    py::class_<StrIssue>(m, "StrIssue")
419        .def(py::init<int>())
420        .def(py::init<>())
421        .def("__str__", [](const StrIssue &si) {
422            return "StrIssue[" + std::to_string(si.val) + "]"; }
423        );
424
425    // test_unregistered_base_implementations
426    //
427    // Issues #854/910: incompatible function args when member function/pointer is in unregistered
428    // base class The methods and member pointers below actually resolve to members/pointers in
429    // UnregisteredBase; before this test/fix they would be registered via lambda with a first
430    // argument of an unregistered type, and thus uncallable.
431    py::class_<RegisteredDerived>(m, "RegisteredDerived")
432        .def(py::init<>())
433        .def("do_nothing", &RegisteredDerived::do_nothing)
434        .def("increase_value", &RegisteredDerived::increase_value)
435        .def_readwrite("rw_value", &RegisteredDerived::rw_value)
436        .def_readonly("ro_value", &RegisteredDerived::ro_value)
437        // These should trigger a static_assert if uncommented
438        //.def_readwrite("fails", &UserType::value) // should trigger a static_assert if uncommented
439        //.def_readonly("fails", &UserType::value) // should trigger a static_assert if uncommented
440        .def_property("rw_value_prop", &RegisteredDerived::get_int, &RegisteredDerived::set_int)
441        .def_property_readonly("ro_value_prop", &RegisteredDerived::get_double)
442        // This one is in the registered class:
443        .def("sum", &RegisteredDerived::sum)
444        ;
445
446    using Adapted = decltype(py::method_adaptor<RegisteredDerived>(&RegisteredDerived::do_nothing));
447    static_assert(std::is_same<Adapted, void (RegisteredDerived::*)() const>::value, "");
448
449    // test_custom_caster_destruction
450    // Test that `take_ownership` works on types with a custom type caster when given a pointer
451
452    // default policy: don't take ownership:
453    m.def("custom_caster_no_destroy", []() { static auto *dt = new DestructionTester(); return dt; });
454
455    m.def("custom_caster_destroy", []() { return new DestructionTester(); },
456            py::return_value_policy::take_ownership); // Takes ownership: destroy when finished
457    m.def("custom_caster_destroy_const", []() -> const DestructionTester * { return new DestructionTester(); },
458            py::return_value_policy::take_ownership); // Likewise (const doesn't inhibit destruction)
459    m.def("destruction_tester_cstats", &ConstructorStats::get<DestructionTester>, py::return_value_policy::reference);
460}
461