test_kwargs_and_defaults.cpp revision 12037:d28054ac6ec9 
1/*
2    tests/test_kwargs_and_defaults.cpp -- keyword arguments and default values
3
4    Copyright (c) 2016 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 <pybind11/stl.h>
12
13std::string kw_func(int x, int y) { return "x=" + std::to_string(x) + ", y=" + std::to_string(y); }
14
15std::string kw_func4(const std::vector<int> &entries) {
16    std::string ret = "{";
17    for (int i : entries)
18        ret += std::to_string(i) + " ";
19    ret.back() = '}';
20    return ret;
21}
22
23py::tuple args_function(py::args args) {
24    return args;
25}
26
27py::tuple args_kwargs_function(py::args args, py::kwargs kwargs) {
28    return py::make_tuple(args, kwargs);
29}
30
31py::tuple mixed_plus_args(int i, double j, py::args args) {
32    return py::make_tuple(i, j, args);
33}
34
35py::tuple mixed_plus_kwargs(int i, double j, py::kwargs kwargs) {
36    return py::make_tuple(i, j, kwargs);
37}
38
39py::tuple mixed_plus_args_kwargs(int i, double j, py::args args, py::kwargs kwargs) {
40    return py::make_tuple(i, j, args, kwargs);
41}
42
43// pybind11 won't allow these to be bound: args and kwargs, if present, must be at the end.
44void bad_args1(py::args, int) {}
45void bad_args2(py::kwargs, int) {}
46void bad_args3(py::kwargs, py::args) {}
47void bad_args4(py::args, int, py::kwargs) {}
48void bad_args5(py::args, py::kwargs, int) {}
49void bad_args6(py::args, py::args) {}
50void bad_args7(py::kwargs, py::kwargs) {}
51
52struct KWClass {
53    void foo(int, float) {}
54};
55
56test_initializer arg_keywords_and_defaults([](py::module &m) {
57    m.def("kw_func0", &kw_func);
58    m.def("kw_func1", &kw_func, py::arg("x"), py::arg("y"));
59    m.def("kw_func2", &kw_func, py::arg("x") = 100, py::arg("y") = 200);
60    m.def("kw_func3", [](const char *) { }, py::arg("data") = std::string("Hello world!"));
61
62    /* A fancier default argument */
63    std::vector<int> list;
64    list.push_back(13);
65    list.push_back(17);
66    m.def("kw_func4", &kw_func4, py::arg("myList") = list);
67
68    m.def("args_function", &args_function);
69    m.def("args_kwargs_function", &args_kwargs_function);
70
71    m.def("kw_func_udl", &kw_func, "x"_a, "y"_a=300);
72    m.def("kw_func_udl_z", &kw_func, "x"_a, "y"_a=0);
73
74    py::class_<KWClass>(m, "KWClass")
75        .def("foo0", &KWClass::foo)
76        .def("foo1", &KWClass::foo, "x"_a, "y"_a);
77
78    m.def("mixed_plus_args", &mixed_plus_args);
79    m.def("mixed_plus_kwargs", &mixed_plus_kwargs);
80    m.def("mixed_plus_args_kwargs", &mixed_plus_args_kwargs);
81
82    m.def("mixed_plus_args_kwargs_defaults", &mixed_plus_args_kwargs,
83            py::arg("i") = 1, py::arg("j") = 3.14159);
84
85    // Uncomment these to test that the static_assert is indeed working:
86//    m.def("bad_args1", &bad_args1);
87//    m.def("bad_args2", &bad_args2);
88//    m.def("bad_args3", &bad_args3);
89//    m.def("bad_args4", &bad_args4);
90//    m.def("bad_args5", &bad_args5);
91//    m.def("bad_args6", &bad_args6);
92//    m.def("bad_args7", &bad_args7);
93});
94