pybind11/example/example-methods-and-attributes.cpp
Jason Rhinelander 3f589379ec Improve constructor/destructor tracking
This commit rewrites the examples that look for constructor/destructor
calls to do so via static variable tracking rather than output parsing.

The added ConstructorStats class provides methods to keep track of
constructors and destructors, number of default/copy/move constructors,
and number of copy/move assignments.  It also provides a mechanism for
storing values (e.g. for value construction), and then allows all of
this to be checked at the end of a test by getting the statistics for a
C++ (or python mapping) class.

By not relying on the precise pattern of constructions/destructions,
but rather simply ensuring that every construction is matched with a
destruction on the same object, we ensure that everything that gets
created also gets destroyed as expected.

This replaces all of the various "std::cout << whatever" code in
constructors/destructors with
`print_created(this)`/`print_destroyed(this)`/etc. functions which
provide similar output, but now has a unified format across the
different examples, including a new ### prefix that makes mixed example
output and lifecycle events easier to distinguish.

With this change, relaxed mode is no longer needed, which enables
testing for proper destruction under MSVC, and under any other compiler
that generates code calling extra constructors, or optimizes away any
constructors.  GCC/clang are used as the baseline for move
constructors; the tests are adapted to allow more move constructors to
be evoked (but other types are constructors much have matching counts).

This commit also disables output buffering of tests, as the buffering
sometimes results in C++ output ending up in the middle of python
output (or vice versa), depending on the OS/python version.
2016-08-11 18:16:04 -04:00

87 lines
4.1 KiB
C++

/*
example/example-methods-and-attributes.cpp -- constructors, deconstructors, attribute access,
__str__, argument and return value conventions
Copyright (c) 2016 Wenzel Jakob <wenzel.jakob@epfl.ch>
All rights reserved. Use of this source code is governed by a
BSD-style license that can be found in the LICENSE file.
*/
#include <unordered_map>
#include <list>
#include "example.h"
#include "constructor-stats.h"
class ExampleMandA {
public:
ExampleMandA() { print_default_created(this); }
ExampleMandA(int value) : value(value) { print_created(this, value); }
ExampleMandA(const ExampleMandA &e) : value(e.value) { print_copy_created(this); }
ExampleMandA(ExampleMandA &&e) : value(e.value) { print_move_created(this); }
~ExampleMandA() { print_destroyed(this); }
std::string toString() {
return "ExampleMandA[value=" + std::to_string(value) + "]";
}
void operator=(const ExampleMandA &e) { print_copy_assigned(this); value = e.value; }
void operator=(ExampleMandA &&e) { print_move_assigned(this); value = e.value; }
void add1(ExampleMandA other) { value += other.value; } // passing by value
void add2(ExampleMandA &other) { value += other.value; } // passing by reference
void add3(const ExampleMandA &other) { value += other.value; } // passing by const reference
void add4(ExampleMandA *other) { value += other->value; } // passing by pointer
void add5(const ExampleMandA *other) { value += other->value; } // passing by const pointer
void add6(int other) { value += other; } // passing by value
void add7(int &other) { value += other; } // passing by reference
void add8(const int &other) { value += other; } // passing by const reference
void add9(int *other) { value += *other; } // passing by pointer
void add10(const int *other) { value += *other; } // passing by const pointer
ExampleMandA self1() { return *this; } // return by value
ExampleMandA &self2() { return *this; } // return by reference
const ExampleMandA &self3() { return *this; } // return by const reference
ExampleMandA *self4() { return this; } // return by pointer
const ExampleMandA *self5() { return this; } // return by const pointer
int internal1() { return value; } // return by value
int &internal2() { return value; } // return by reference
const int &internal3() { return value; } // return by const reference
int *internal4() { return &value; } // return by pointer
const int *internal5() { return &value; } // return by const pointer
int value = 0;
};
void init_ex_methods_and_attributes(py::module &m) {
py::class_<ExampleMandA>(m, "ExampleMandA")
.def(py::init<>())
.def(py::init<int>())
.def(py::init<const ExampleMandA&>())
.def("add1", &ExampleMandA::add1)
.def("add2", &ExampleMandA::add2)
.def("add3", &ExampleMandA::add3)
.def("add4", &ExampleMandA::add4)
.def("add5", &ExampleMandA::add5)
.def("add6", &ExampleMandA::add6)
.def("add7", &ExampleMandA::add7)
.def("add8", &ExampleMandA::add8)
.def("add9", &ExampleMandA::add9)
.def("add10", &ExampleMandA::add10)
.def("self1", &ExampleMandA::self1)
.def("self2", &ExampleMandA::self2)
.def("self3", &ExampleMandA::self3)
.def("self4", &ExampleMandA::self4)
.def("self5", &ExampleMandA::self5)
.def("internal1", &ExampleMandA::internal1)
.def("internal2", &ExampleMandA::internal2)
.def("internal3", &ExampleMandA::internal3)
.def("internal4", &ExampleMandA::internal4)
.def("internal5", &ExampleMandA::internal5)
.def("__str__", &ExampleMandA::toString)
.def_readwrite("value", &ExampleMandA::value)
;
}