test_methods_and_attributes.cpp revision 12391:ceeca8b41e4b 
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
14class ExampleMandA {
15public:
16    ExampleMandA() { print_default_created(this); }
17    ExampleMandA(int value) : value(value) { print_created(this, value); }
18    ExampleMandA(const ExampleMandA &e) : value(e.value) { print_copy_created(this); }
19    ExampleMandA(ExampleMandA &&e) : value(e.value) { print_move_created(this); }
20    ~ExampleMandA() { print_destroyed(this); }
21
22    std::string toString() {
23        return "ExampleMandA[value=" + std::to_string(value) + "]";
24    }
25
26    void operator=(const ExampleMandA &e) { print_copy_assigned(this); value = e.value; }
27    void operator=(ExampleMandA &&e) { print_move_assigned(this); value = e.value; }
28
29    void add1(ExampleMandA other) { value += other.value; }         // passing by value
30    void add2(ExampleMandA &other) { value += other.value; }        // passing by reference
31    void add3(const ExampleMandA &other) { value += other.value; }  // passing by const reference
32    void add4(ExampleMandA *other) { value += other->value; }       // passing by pointer
33    void add5(const ExampleMandA *other) { value += other->value; } // passing by const pointer
34
35    void add6(int other) { value += other; }                        // passing by value
36    void add7(int &other) { value += other; }                       // passing by reference
37    void add8(const int &other) { value += other; }                 // passing by const reference
38    void add9(int *other) { value += *other; }                      // passing by pointer
39    void add10(const int *other) { value += *other; }               // passing by const pointer
40
41    ExampleMandA self1() { return *this; }                          // return by value
42    ExampleMandA &self2() { return *this; }                         // return by reference
43    const ExampleMandA &self3() { return *this; }                   // return by const reference
44    ExampleMandA *self4() { return this; }                          // return by pointer
45    const ExampleMandA *self5() { return this; }                    // return by const pointer
46
47    int internal1() { return value; }                               // return by value
48    int &internal2() { return value; }                              // return by reference
49    const int &internal3() { return value; }                        // return by const reference
50    int *internal4() { return &value; }                             // return by pointer
51    const int *internal5() { return &value; }                       // return by const pointer
52
53    py::str overloaded()             { return "()"; }
54    py::str overloaded(int)          { return "(int)"; }
55    py::str overloaded(int, float)   { return "(int, float)"; }
56    py::str overloaded(float, int)   { return "(float, int)"; }
57    py::str overloaded(int, int)     { return "(int, int)"; }
58    py::str overloaded(float, float) { return "(float, float)"; }
59    py::str overloaded(int)          const { return "(int) const"; }
60    py::str overloaded(int, float)   const { return "(int, float) const"; }
61    py::str overloaded(float, int)   const { return "(float, int) const"; }
62    py::str overloaded(int, int)     const { return "(int, int) const"; }
63    py::str overloaded(float, float) const { return "(float, float) const"; }
64
65    static py::str overloaded(float) { return "static float"; }
66
67    int value = 0;
68};
69
70struct TestProperties {
71    int value = 1;
72    static int static_value;
73
74    int get() const { return value; }
75    void set(int v) { value = v; }
76
77    static int static_get() { return static_value; }
78    static void static_set(int v) { static_value = v; }
79};
80int TestProperties::static_value = 1;
81
82struct TestPropertiesOverride : TestProperties {
83    int value = 99;
84    static int static_value;
85};
86int TestPropertiesOverride::static_value = 99;
87
88struct TestPropRVP {
89    UserType v1{1};
90    UserType v2{1};
91    static UserType sv1;
92    static UserType sv2;
93
94    const UserType &get1() const { return v1; }
95    const UserType &get2() const { return v2; }
96    UserType get_rvalue() const { return v2; }
97    void set1(int v) { v1.set(v); }
98    void set2(int v) { v2.set(v); }
99};
100UserType TestPropRVP::sv1(1);
101UserType TestPropRVP::sv2(1);
102
103// py::arg/py::arg_v testing: these arguments just record their argument when invoked
104class ArgInspector1 { public: std::string arg = "(default arg inspector 1)"; };
105class ArgInspector2 { public: std::string arg = "(default arg inspector 2)"; };
106class ArgAlwaysConverts { };
107namespace pybind11 { namespace detail {
108template <> struct type_caster<ArgInspector1> {
109public:
110    PYBIND11_TYPE_CASTER(ArgInspector1, _("ArgInspector1"));
111
112    bool load(handle src, bool convert) {
113        value.arg = "loading ArgInspector1 argument " +
114            std::string(convert ? "WITH" : "WITHOUT") + " conversion allowed.  "
115            "Argument value = " + (std::string) str(src);
116        return true;
117    }
118
119    static handle cast(const ArgInspector1 &src, return_value_policy, handle) {
120        return str(src.arg).release();
121    }
122};
123template <> struct type_caster<ArgInspector2> {
124public:
125    PYBIND11_TYPE_CASTER(ArgInspector2, _("ArgInspector2"));
126
127    bool load(handle src, bool convert) {
128        value.arg = "loading ArgInspector2 argument " +
129            std::string(convert ? "WITH" : "WITHOUT") + " conversion allowed.  "
130            "Argument value = " + (std::string) str(src);
131        return true;
132    }
133
134    static handle cast(const ArgInspector2 &src, return_value_policy, handle) {
135        return str(src.arg).release();
136    }
137};
138template <> struct type_caster<ArgAlwaysConverts> {
139public:
140    PYBIND11_TYPE_CASTER(ArgAlwaysConverts, _("ArgAlwaysConverts"));
141
142    bool load(handle, bool convert) {
143        return convert;
144    }
145
146    static handle cast(const ArgAlwaysConverts &, return_value_policy, handle) {
147        return py::none().release();
148    }
149};
150}}
151
152// test_custom_caster_destruction
153class DestructionTester {
154public:
155    DestructionTester() { print_default_created(this); }
156    ~DestructionTester() { print_destroyed(this); }
157    DestructionTester(const DestructionTester &) { print_copy_created(this); }
158    DestructionTester(DestructionTester &&) { print_move_created(this); }
159    DestructionTester &operator=(const DestructionTester &) { print_copy_assigned(this); return *this; }
160    DestructionTester &operator=(DestructionTester &&) { print_move_assigned(this); return *this; }
161};
162namespace pybind11 { namespace detail {
163template <> struct type_caster<DestructionTester> {
164    PYBIND11_TYPE_CASTER(DestructionTester, _("DestructionTester"));
165    bool load(handle, bool) { return true; }
166
167    static handle cast(const DestructionTester &, return_value_policy, handle) {
168        return py::bool_(true).release();
169    }
170};
171}}
172
173// Test None-allowed py::arg argument policy
174class NoneTester { public: int answer = 42; };
175int none1(const NoneTester &obj) { return obj.answer; }
176int none2(NoneTester *obj) { return obj ? obj->answer : -1; }
177int none3(std::shared_ptr<NoneTester> &obj) { return obj ? obj->answer : -1; }
178int none4(std::shared_ptr<NoneTester> *obj) { return obj && *obj ? (*obj)->answer : -1; }
179int none5(std::shared_ptr<NoneTester> obj) { return obj ? obj->answer : -1; }
180
181struct StrIssue {
182    int val = -1;
183
184    StrIssue() = default;
185    StrIssue(int i) : val{i} {}
186};
187
188// Issues #854, #910: incompatible function args when member function/pointer is in unregistered base class
189class UnregisteredBase {
190public:
191    void do_nothing() const {}
192    void increase_value() { rw_value++; ro_value += 0.25; }
193    void set_int(int v) { rw_value = v; }
194    int get_int() const { return rw_value; }
195    double get_double() const { return ro_value; }
196    int rw_value = 42;
197    double ro_value = 1.25;
198};
199class RegisteredDerived : public UnregisteredBase {
200public:
201    using UnregisteredBase::UnregisteredBase;
202    double sum() const { return rw_value + ro_value; }
203};
204
205TEST_SUBMODULE(methods_and_attributes, m) {
206    // test_methods_and_attributes
207    py::class_<ExampleMandA> emna(m, "ExampleMandA");
208    emna.def(py::init<>())
209        .def(py::init<int>())
210        .def(py::init<const ExampleMandA&>())
211        .def("add1", &ExampleMandA::add1)
212        .def("add2", &ExampleMandA::add2)
213        .def("add3", &ExampleMandA::add3)
214        .def("add4", &ExampleMandA::add4)
215        .def("add5", &ExampleMandA::add5)
216        .def("add6", &ExampleMandA::add6)
217        .def("add7", &ExampleMandA::add7)
218        .def("add8", &ExampleMandA::add8)
219        .def("add9", &ExampleMandA::add9)
220        .def("add10", &ExampleMandA::add10)
221        .def("self1", &ExampleMandA::self1)
222        .def("self2", &ExampleMandA::self2)
223        .def("self3", &ExampleMandA::self3)
224        .def("self4", &ExampleMandA::self4)
225        .def("self5", &ExampleMandA::self5)
226        .def("internal1", &ExampleMandA::internal1)
227        .def("internal2", &ExampleMandA::internal2)
228        .def("internal3", &ExampleMandA::internal3)
229        .def("internal4", &ExampleMandA::internal4)
230        .def("internal5", &ExampleMandA::internal5)
231#if defined(PYBIND11_OVERLOAD_CAST)
232        .def("overloaded", py::overload_cast<>(&ExampleMandA::overloaded))
233        .def("overloaded", py::overload_cast<int>(&ExampleMandA::overloaded))
234        .def("overloaded", py::overload_cast<int,   float>(&ExampleMandA::overloaded))
235        .def("overloaded", py::overload_cast<float,   int>(&ExampleMandA::overloaded))
236        .def("overloaded", py::overload_cast<int,     int>(&ExampleMandA::overloaded))
237        .def("overloaded", py::overload_cast<float, float>(&ExampleMandA::overloaded))
238        .def("overloaded_float", py::overload_cast<float, float>(&ExampleMandA::overloaded))
239        .def("overloaded_const", py::overload_cast<int         >(&ExampleMandA::overloaded, py::const_))
240        .def("overloaded_const", py::overload_cast<int,   float>(&ExampleMandA::overloaded, py::const_))
241        .def("overloaded_const", py::overload_cast<float,   int>(&ExampleMandA::overloaded, py::const_))
242        .def("overloaded_const", py::overload_cast<int,     int>(&ExampleMandA::overloaded, py::const_))
243        .def("overloaded_const", py::overload_cast<float, float>(&ExampleMandA::overloaded, py::const_))
244#else
245        .def("overloaded", static_cast<py::str (ExampleMandA::*)()>(&ExampleMandA::overloaded))
246        .def("overloaded", static_cast<py::str (ExampleMandA::*)(int)>(&ExampleMandA::overloaded))
247        .def("overloaded", static_cast<py::str (ExampleMandA::*)(int,   float)>(&ExampleMandA::overloaded))
248        .def("overloaded", static_cast<py::str (ExampleMandA::*)(float,   int)>(&ExampleMandA::overloaded))
249        .def("overloaded", static_cast<py::str (ExampleMandA::*)(int,     int)>(&ExampleMandA::overloaded))
250        .def("overloaded", static_cast<py::str (ExampleMandA::*)(float, float)>(&ExampleMandA::overloaded))
251        .def("overloaded_float", static_cast<py::str (ExampleMandA::*)(float, float)>(&ExampleMandA::overloaded))
252        .def("overloaded_const", static_cast<py::str (ExampleMandA::*)(int         ) const>(&ExampleMandA::overloaded))
253        .def("overloaded_const", static_cast<py::str (ExampleMandA::*)(int,   float) const>(&ExampleMandA::overloaded))
254        .def("overloaded_const", static_cast<py::str (ExampleMandA::*)(float,   int) const>(&ExampleMandA::overloaded))
255        .def("overloaded_const", static_cast<py::str (ExampleMandA::*)(int,     int) const>(&ExampleMandA::overloaded))
256        .def("overloaded_const", static_cast<py::str (ExampleMandA::*)(float, float) const>(&ExampleMandA::overloaded))
257#endif
258        // test_no_mixed_overloads
259        // Raise error if trying to mix static/non-static overloads on the same name:
260        .def_static("add_mixed_overloads1", []() {
261            auto emna = py::reinterpret_borrow<py::class_<ExampleMandA>>(py::module::import("pybind11_tests.methods_and_attributes").attr("ExampleMandA"));
262            emna.def       ("overload_mixed1", static_cast<py::str (ExampleMandA::*)(int, int)>(&ExampleMandA::overloaded))
263                .def_static("overload_mixed1", static_cast<py::str (              *)(float   )>(&ExampleMandA::overloaded));
264        })
265        .def_static("add_mixed_overloads2", []() {
266            auto emna = py::reinterpret_borrow<py::class_<ExampleMandA>>(py::module::import("pybind11_tests.methods_and_attributes").attr("ExampleMandA"));
267            emna.def_static("overload_mixed2", static_cast<py::str (              *)(float   )>(&ExampleMandA::overloaded))
268                .def       ("overload_mixed2", static_cast<py::str (ExampleMandA::*)(int, int)>(&ExampleMandA::overloaded));
269        })
270        .def("__str__", &ExampleMandA::toString)
271        .def_readwrite("value", &ExampleMandA::value);
272
273    // test_copy_method
274    // Issue #443: can't call copied methods in Python 3
275    emna.attr("add2b") = emna.attr("add2");
276
277    // test_properties, test_static_properties, test_static_cls
278    py::class_<TestProperties>(m, "TestProperties")
279        .def(py::init<>())
280        .def_readonly("def_readonly", &TestProperties::value)
281        .def_readwrite("def_readwrite", &TestProperties::value)
282        .def_property_readonly("def_property_readonly", &TestProperties::get)
283        .def_property("def_property", &TestProperties::get, &TestProperties::set)
284        .def_readonly_static("def_readonly_static", &TestProperties::static_value)
285        .def_readwrite_static("def_readwrite_static", &TestProperties::static_value)
286        .def_property_readonly_static("def_property_readonly_static",
287                                      [](py::object) { return TestProperties::static_get(); })
288        .def_property_static("def_property_static",
289                             [](py::object) { return TestProperties::static_get(); },
290                             [](py::object, int v) { TestProperties::static_set(v); })
291        .def_property_static("static_cls",
292                             [](py::object cls) { return cls; },
293                             [](py::object cls, py::function f) { f(cls); });
294
295    py::class_<TestPropertiesOverride, TestProperties>(m, "TestPropertiesOverride")
296        .def(py::init<>())
297        .def_readonly("def_readonly", &TestPropertiesOverride::value)
298        .def_readonly_static("def_readonly_static", &TestPropertiesOverride::static_value);
299
300    auto static_get1 = [](py::object) -> const UserType & { return TestPropRVP::sv1; };
301    auto static_get2 = [](py::object) -> const UserType & { return TestPropRVP::sv2; };
302    auto static_set1 = [](py::object, int v) { TestPropRVP::sv1.set(v); };
303    auto static_set2 = [](py::object, int v) { TestPropRVP::sv2.set(v); };
304    auto rvp_copy = py::return_value_policy::copy;
305
306    // test_property_return_value_policies
307    py::class_<TestPropRVP>(m, "TestPropRVP")
308        .def(py::init<>())
309        .def_property_readonly("ro_ref", &TestPropRVP::get1)
310        .def_property_readonly("ro_copy", &TestPropRVP::get2, rvp_copy)
311        .def_property_readonly("ro_func", py::cpp_function(&TestPropRVP::get2, rvp_copy))
312        .def_property("rw_ref", &TestPropRVP::get1, &TestPropRVP::set1)
313        .def_property("rw_copy", &TestPropRVP::get2, &TestPropRVP::set2, rvp_copy)
314        .def_property("rw_func", py::cpp_function(&TestPropRVP::get2, rvp_copy), &TestPropRVP::set2)
315        .def_property_readonly_static("static_ro_ref", static_get1)
316        .def_property_readonly_static("static_ro_copy", static_get2, rvp_copy)
317        .def_property_readonly_static("static_ro_func", py::cpp_function(static_get2, rvp_copy))
318        .def_property_static("static_rw_ref", static_get1, static_set1)
319        .def_property_static("static_rw_copy", static_get2, static_set2, rvp_copy)
320        .def_property_static("static_rw_func", py::cpp_function(static_get2, rvp_copy), static_set2)
321        // test_property_rvalue_policy
322        .def_property_readonly("rvalue", &TestPropRVP::get_rvalue)
323        .def_property_readonly_static("static_rvalue", [](py::object) { return UserType(1); });
324
325    // test_metaclass_override
326    struct MetaclassOverride { };
327    py::class_<MetaclassOverride>(m, "MetaclassOverride", py::metaclass((PyObject *) &PyType_Type))
328        .def_property_readonly_static("readonly", [](py::object) { return 1; });
329
330#if !defined(PYPY_VERSION)
331    // test_dynamic_attributes
332    class DynamicClass {
333    public:
334        DynamicClass() { print_default_created(this); }
335        ~DynamicClass() { print_destroyed(this); }
336    };
337    py::class_<DynamicClass>(m, "DynamicClass", py::dynamic_attr())
338        .def(py::init());
339
340    class CppDerivedDynamicClass : public DynamicClass { };
341    py::class_<CppDerivedDynamicClass, DynamicClass>(m, "CppDerivedDynamicClass")
342        .def(py::init());
343#endif
344
345    // test_noconvert_args
346    //
347    // Test converting.  The ArgAlwaysConverts is just there to make the first no-conversion pass
348    // fail so that our call always ends up happening via the second dispatch (the one that allows
349    // some conversion).
350    class ArgInspector {
351    public:
352        ArgInspector1 f(ArgInspector1 a, ArgAlwaysConverts) { return a; }
353        std::string g(ArgInspector1 a, const ArgInspector1 &b, int c, ArgInspector2 *d, ArgAlwaysConverts) {
354            return a.arg + "\n" + b.arg + "\n" + std::to_string(c) + "\n" + d->arg;
355        }
356        static ArgInspector2 h(ArgInspector2 a, ArgAlwaysConverts) { return a; }
357    };
358    py::class_<ArgInspector>(m, "ArgInspector")
359        .def(py::init<>())
360        .def("f", &ArgInspector::f, py::arg(), py::arg() = ArgAlwaysConverts())
361        .def("g", &ArgInspector::g, "a"_a.noconvert(), "b"_a, "c"_a.noconvert()=13, "d"_a=ArgInspector2(), py::arg() = ArgAlwaysConverts())
362        .def_static("h", &ArgInspector::h, py::arg().noconvert(), py::arg() = ArgAlwaysConverts())
363        ;
364    m.def("arg_inspect_func", [](ArgInspector2 a, ArgInspector1 b, ArgAlwaysConverts) { return a.arg + "\n" + b.arg; },
365            py::arg().noconvert(false), py::arg_v(nullptr, ArgInspector1()).noconvert(true), py::arg() = ArgAlwaysConverts());
366
367    m.def("floats_preferred", [](double f) { return 0.5 * f; }, py::arg("f"));
368    m.def("floats_only", [](double f) { return 0.5 * f; }, py::arg("f").noconvert());
369    m.def("ints_preferred", [](int i) { return i / 2; }, py::arg("i"));
370    m.def("ints_only", [](int i) { return i / 2; }, py::arg("i").noconvert());
371
372    // test_bad_arg_default
373    // Issue/PR #648: bad arg default debugging output
374#if !defined(NDEBUG)
375    m.attr("debug_enabled") = true;
376#else
377    m.attr("debug_enabled") = false;
378#endif
379    m.def("bad_arg_def_named", []{
380        auto m = py::module::import("pybind11_tests");
381        m.def("should_fail", [](int, UnregisteredType) {}, py::arg(), py::arg("a") = UnregisteredType());
382    });
383    m.def("bad_arg_def_unnamed", []{
384        auto m = py::module::import("pybind11_tests");
385        m.def("should_fail", [](int, UnregisteredType) {}, py::arg(), py::arg() = UnregisteredType());
386    });
387
388    // test_accepts_none
389    py::class_<NoneTester, std::shared_ptr<NoneTester>>(m, "NoneTester")
390        .def(py::init<>());
391    m.def("no_none1", &none1, py::arg().none(false));
392    m.def("no_none2", &none2, py::arg().none(false));
393    m.def("no_none3", &none3, py::arg().none(false));
394    m.def("no_none4", &none4, py::arg().none(false));
395    m.def("no_none5", &none5, py::arg().none(false));
396    m.def("ok_none1", &none1);
397    m.def("ok_none2", &none2, py::arg().none(true));
398    m.def("ok_none3", &none3);
399    m.def("ok_none4", &none4, py::arg().none(true));
400    m.def("ok_none5", &none5);
401
402    // test_str_issue
403    // Issue #283: __str__ called on uninitialized instance when constructor arguments invalid
404    py::class_<StrIssue>(m, "StrIssue")
405        .def(py::init<int>())
406        .def(py::init<>())
407        .def("__str__", [](const StrIssue &si) {
408            return "StrIssue[" + std::to_string(si.val) + "]"; }
409        );
410
411    // test_unregistered_base_implementations
412    //
413    // Issues #854/910: incompatible function args when member function/pointer is in unregistered
414    // base class The methods and member pointers below actually resolve to members/pointers in
415    // UnregisteredBase; before this test/fix they would be registered via lambda with a first
416    // argument of an unregistered type, and thus uncallable.
417    py::class_<RegisteredDerived>(m, "RegisteredDerived")
418        .def(py::init<>())
419        .def("do_nothing", &RegisteredDerived::do_nothing)
420        .def("increase_value", &RegisteredDerived::increase_value)
421        .def_readwrite("rw_value", &RegisteredDerived::rw_value)
422        .def_readonly("ro_value", &RegisteredDerived::ro_value)
423        // These should trigger a static_assert if uncommented
424        //.def_readwrite("fails", &UserType::value) // should trigger a static_assert if uncommented
425        //.def_readonly("fails", &UserType::value) // should trigger a static_assert if uncommented
426        .def_property("rw_value_prop", &RegisteredDerived::get_int, &RegisteredDerived::set_int)
427        .def_property_readonly("ro_value_prop", &RegisteredDerived::get_double)
428        // This one is in the registered class:
429        .def("sum", &RegisteredDerived::sum)
430        ;
431
432    using Adapted = decltype(py::method_adaptor<RegisteredDerived>(&RegisteredDerived::do_nothing));
433    static_assert(std::is_same<Adapted, void (RegisteredDerived::*)() const>::value, "");
434
435    // test_custom_caster_destruction
436    // Test that `take_ownership` works on types with a custom type caster when given a pointer
437
438    // default policy: don't take ownership:
439    m.def("custom_caster_no_destroy", []() { static auto *dt = new DestructionTester(); return dt; });
440
441    m.def("custom_caster_destroy", []() { return new DestructionTester(); },
442            py::return_value_policy::take_ownership); // Takes ownership: destroy when finished
443    m.def("custom_caster_destroy_const", []() -> const DestructionTester * { return new DestructionTester(); },
444            py::return_value_policy::take_ownership); // Likewise (const doesn't inhibit destruction)
445    m.def("destruction_tester_cstats", &ConstructorStats::get<DestructionTester>, py::return_value_policy::reference);
446}
447