test_pytypes.cpp revision 14299:2fbea9df56d2 
1/*
2    tests/test_pytypes.cpp -- Python 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
12
13TEST_SUBMODULE(pytypes, m) {
14    // test_list
15    m.def("get_list", []() {
16        py::list list;
17        list.append("value");
18        py::print("Entry at position 0:", list[0]);
19        list[0] = py::str("overwritten");
20        list.insert(0, "inserted-0");
21        list.insert(2, "inserted-2");
22        return list;
23    });
24    m.def("print_list", [](py::list list) {
25        int index = 0;
26        for (auto item : list)
27            py::print("list item {}: {}"_s.format(index++, item));
28    });
29
30    // test_set
31    m.def("get_set", []() {
32        py::set set;
33        set.add(py::str("key1"));
34        set.add("key2");
35        set.add(std::string("key3"));
36        return set;
37    });
38    m.def("print_set", [](py::set set) {
39        for (auto item : set)
40            py::print("key:", item);
41    });
42    m.def("set_contains", [](py::set set, py::object key) {
43        return set.contains(key);
44    });
45    m.def("set_contains", [](py::set set, const char* key) {
46        return set.contains(key);
47    });
48
49    // test_dict
50    m.def("get_dict", []() { return py::dict("key"_a="value"); });
51    m.def("print_dict", [](py::dict dict) {
52        for (auto item : dict)
53            py::print("key: {}, value={}"_s.format(item.first, item.second));
54    });
55    m.def("dict_keyword_constructor", []() {
56        auto d1 = py::dict("x"_a=1, "y"_a=2);
57        auto d2 = py::dict("z"_a=3, **d1);
58        return d2;
59    });
60    m.def("dict_contains", [](py::dict dict, py::object val) {
61        return dict.contains(val);
62    });
63    m.def("dict_contains", [](py::dict dict, const char* val) {
64        return dict.contains(val);
65    });
66
67    // test_str
68    m.def("str_from_string", []() { return py::str(std::string("baz")); });
69    m.def("str_from_bytes", []() { return py::str(py::bytes("boo", 3)); });
70    m.def("str_from_object", [](const py::object& obj) { return py::str(obj); });
71    m.def("repr_from_object", [](const py::object& obj) { return py::repr(obj); });
72
73    m.def("str_format", []() {
74        auto s1 = "{} + {} = {}"_s.format(1, 2, 3);
75        auto s2 = "{a} + {b} = {c}"_s.format("a"_a=1, "b"_a=2, "c"_a=3);
76        return py::make_tuple(s1, s2);
77    });
78
79    // test_bytes
80    m.def("bytes_from_string", []() { return py::bytes(std::string("foo")); });
81    m.def("bytes_from_str", []() { return py::bytes(py::str("bar", 3)); });
82
83    // test_capsule
84    m.def("return_capsule_with_destructor", []() {
85        py::print("creating capsule");
86        return py::capsule([]() {
87            py::print("destructing capsule");
88        });
89    });
90
91    m.def("return_capsule_with_destructor_2", []() {
92        py::print("creating capsule");
93        return py::capsule((void *) 1234, [](void *ptr) {
94            py::print("destructing capsule: {}"_s.format((size_t) ptr));
95        });
96    });
97
98    m.def("return_capsule_with_name_and_destructor", []() {
99        auto capsule = py::capsule((void *) 1234, "pointer type description", [](PyObject *ptr) {
100            if (ptr) {
101                auto name = PyCapsule_GetName(ptr);
102                py::print("destructing capsule ({}, '{}')"_s.format(
103                    (size_t) PyCapsule_GetPointer(ptr, name), name
104                ));
105            }
106        });
107        void *contents = capsule;
108        py::print("created capsule ({}, '{}')"_s.format((size_t) contents, capsule.name()));
109        return capsule;
110    });
111
112    // test_accessors
113    m.def("accessor_api", [](py::object o) {
114        auto d = py::dict();
115
116        d["basic_attr"] = o.attr("basic_attr");
117
118        auto l = py::list();
119        for (const auto &item : o.attr("begin_end")) {
120            l.append(item);
121        }
122        d["begin_end"] = l;
123
124        d["operator[object]"] = o.attr("d")["operator[object]"_s];
125        d["operator[char *]"] = o.attr("d")["operator[char *]"];
126
127        d["attr(object)"] = o.attr("sub").attr("attr_obj");
128        d["attr(char *)"] = o.attr("sub").attr("attr_char");
129        try {
130            o.attr("sub").attr("missing").ptr();
131        } catch (const py::error_already_set &) {
132            d["missing_attr_ptr"] = "raised"_s;
133        }
134        try {
135            o.attr("missing").attr("doesn't matter");
136        } catch (const py::error_already_set &) {
137            d["missing_attr_chain"] = "raised"_s;
138        }
139
140        d["is_none"] = o.attr("basic_attr").is_none();
141
142        d["operator()"] = o.attr("func")(1);
143        d["operator*"] = o.attr("func")(*o.attr("begin_end"));
144
145        // Test implicit conversion
146        py::list implicit_list = o.attr("begin_end");
147        d["implicit_list"] = implicit_list;
148        py::dict implicit_dict = o.attr("__dict__");
149        d["implicit_dict"] = implicit_dict;
150
151        return d;
152    });
153
154    m.def("tuple_accessor", [](py::tuple existing_t) {
155        try {
156            existing_t[0] = 1;
157        } catch (const py::error_already_set &) {
158            // --> Python system error
159            // Only new tuples (refcount == 1) are mutable
160            auto new_t = py::tuple(3);
161            for (size_t i = 0; i < new_t.size(); ++i) {
162                new_t[i] = i;
163            }
164            return new_t;
165        }
166        return py::tuple();
167    });
168
169    m.def("accessor_assignment", []() {
170        auto l = py::list(1);
171        l[0] = 0;
172
173        auto d = py::dict();
174        d["get"] = l[0];
175        auto var = l[0];
176        d["deferred_get"] = var;
177        l[0] = 1;
178        d["set"] = l[0];
179        var = 99; // this assignment should not overwrite l[0]
180        d["deferred_set"] = l[0];
181        d["var"] = var;
182
183        return d;
184    });
185
186    // test_constructors
187    m.def("default_constructors", []() {
188        return py::dict(
189            "str"_a=py::str(),
190            "bool"_a=py::bool_(),
191            "int"_a=py::int_(),
192            "float"_a=py::float_(),
193            "tuple"_a=py::tuple(),
194            "list"_a=py::list(),
195            "dict"_a=py::dict(),
196            "set"_a=py::set()
197        );
198    });
199
200    m.def("converting_constructors", [](py::dict d) {
201        return py::dict(
202            "str"_a=py::str(d["str"]),
203            "bool"_a=py::bool_(d["bool"]),
204            "int"_a=py::int_(d["int"]),
205            "float"_a=py::float_(d["float"]),
206            "tuple"_a=py::tuple(d["tuple"]),
207            "list"_a=py::list(d["list"]),
208            "dict"_a=py::dict(d["dict"]),
209            "set"_a=py::set(d["set"]),
210            "memoryview"_a=py::memoryview(d["memoryview"])
211        );
212    });
213
214    m.def("cast_functions", [](py::dict d) {
215        // When converting between Python types, obj.cast<T>() should be the same as T(obj)
216        return py::dict(
217            "str"_a=d["str"].cast<py::str>(),
218            "bool"_a=d["bool"].cast<py::bool_>(),
219            "int"_a=d["int"].cast<py::int_>(),
220            "float"_a=d["float"].cast<py::float_>(),
221            "tuple"_a=d["tuple"].cast<py::tuple>(),
222            "list"_a=d["list"].cast<py::list>(),
223            "dict"_a=d["dict"].cast<py::dict>(),
224            "set"_a=d["set"].cast<py::set>(),
225            "memoryview"_a=d["memoryview"].cast<py::memoryview>()
226        );
227    });
228
229    m.def("get_implicit_casting", []() {
230        py::dict d;
231        d["char*_i1"] = "abc";
232        const char *c2 = "abc";
233        d["char*_i2"] = c2;
234        d["char*_e"] = py::cast(c2);
235        d["char*_p"] = py::str(c2);
236
237        d["int_i1"] = 42;
238        int i = 42;
239        d["int_i2"] = i;
240        i++;
241        d["int_e"] = py::cast(i);
242        i++;
243        d["int_p"] = py::int_(i);
244
245        d["str_i1"] = std::string("str");
246        std::string s2("str1");
247        d["str_i2"] = s2;
248        s2[3] = '2';
249        d["str_e"] = py::cast(s2);
250        s2[3] = '3';
251        d["str_p"] = py::str(s2);
252
253        py::list l(2);
254        l[0] = 3;
255        l[1] = py::cast(6);
256        l.append(9);
257        l.append(py::cast(12));
258        l.append(py::int_(15));
259
260        return py::dict(
261            "d"_a=d,
262            "l"_a=l
263        );
264    });
265
266    // test_print
267    m.def("print_function", []() {
268        py::print("Hello, World!");
269        py::print(1, 2.0, "three", true, std::string("-- multiple args"));
270        auto args = py::make_tuple("and", "a", "custom", "separator");
271        py::print("*args", *args, "sep"_a="-");
272        py::print("no new line here", "end"_a=" -- ");
273        py::print("next print");
274
275        auto py_stderr = py::module::import("sys").attr("stderr");
276        py::print("this goes to stderr", "file"_a=py_stderr);
277
278        py::print("flush", "flush"_a=true);
279
280        py::print("{a} + {b} = {c}"_s.format("a"_a="py::print", "b"_a="str.format", "c"_a="this"));
281    });
282
283    m.def("print_failure", []() { py::print(42, UnregisteredType()); });
284
285    m.def("hash_function", [](py::object obj) { return py::hash(obj); });
286
287    m.def("test_number_protocol", [](py::object a, py::object b) {
288        py::list l;
289        l.append(a.equal(b));
290        l.append(a.not_equal(b));
291        l.append(a < b);
292        l.append(a <= b);
293        l.append(a > b);
294        l.append(a >= b);
295        l.append(a + b);
296        l.append(a - b);
297        l.append(a * b);
298        l.append(a / b);
299        l.append(a | b);
300        l.append(a & b);
301        l.append(a ^ b);
302        l.append(a >> b);
303        l.append(a << b);
304        return l;
305    });
306
307    m.def("test_list_slicing", [](py::list a) {
308        return a[py::slice(0, -1, 2)];
309    });
310}
311