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/* Copyright (C) 2013 The libsigc++ Development Team
*
* This file is part of libsigc++.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
// The purpose of this test case is threefold.
// - Test sigc::track_obj().
// - Show that a slot with a C++11 lambda expression can be automatically
// disconnected when an object derived from sigc::trackable is deleted,
// provided sigc::track_obj() is used.
// It's shown here as a preparation for deprecating and eventually
// deleting the libsigc++ lambda expressions.
// See https://bugzilla.gnome.org/show_bug.cgi?id=672555
// - Test the code example in the documentation in sigc++/adaptors/track_obj.h.
//
// To test the C++11 lambda expressions with gcc 4.6.3 (and probably some later
// versions of gcc; gcc 4.7.x also understands -std=c++11):
// make CXXFLAGS='-g -O2 -std=c++0x' test_track_obj
// ./test_track_obj
// echo $?
// If test_track_obj writes nothing and the return code is 0, the test has passed.
#include "testutilities.h"
#include <string>
#include <iostream>
#include <sstream>
#include <cstdlib>
#include <sigc++/adaptors/track_obj.h>
#include <sigc++/signal.h>
namespace
{
std::ostringstream result_stream;
struct book : public sigc::trackable
{
explicit book(const std::string& name) : name_(name) {}
operator std::string& () { return name_; }
operator const std::string& () const { return name_; }
std::string name_;
};
struct bar_group4 : public sigc::trackable
{
};
class Functor1 : public sigc::functor_base
{
public:
typedef std::string result_type;
Functor1(const bar_group4& bar)
: bar_(bar) {}
std::string operator()(int i)
{
return (i<0) ? "negative" : ((i>0) ? "positive" : "zero");
}
private:
const bar_group4& bar_;
};
class Functor2 : public sigc::functor_base
{
public:
typedef std::string result_type;
Functor2(const bar_group4& bar, const book& aBook)
: bar_(bar), aBook_(aBook) {}
std::string operator()(int i, const std::string& str) const
{
std::string result = (i<0) ? "negative, " : ((i>0) ? "positive, " : "zero, ");
result += str;
result += aBook_;
return result;
}
private:
const bar_group4& bar_;
const book& aBook_;
};
//C++11 lamba expressions:
inline std::ostringstream& operator << (std::ostringstream& s, const book& b)
{
s << b.name_;
return s;
}
void egon(std::string& str)
{
result_stream << "egon(string '" << str << "')";
str = "egon was here";
}
void foo_group4(bar_group4&)
{
result_stream << "foo_group4(bar_group4&)";
}
} // end anonymous namespace
int main(int argc, char* argv[])
{
auto util = TestUtilities::get_instance();
if (!util->check_command_args(argc, argv))
return util->get_result_and_delete_instance() ? EXIT_SUCCESS : EXIT_FAILURE;
sigc::slot<std::string, int> sl1;
{
bar_group4 bar4;
sl1 = sigc::track_obj(Functor1(bar4), bar4);
result_stream << sl1(-2);
util->check_result(result_stream, "negative");
} // auto-disconnect sl1
result_stream << sl1(-2);
util->check_result(result_stream, "");
// Allocate on the heap. valgrind can then find erroneous memory accesses.
// (There should be none, of course.)
auto psl2 = new sigc::slot<std::string, int, std::string>;
bar_group4* pbar4 = new bar_group4;
book* pbook4 = new book("A Book");
*psl2 = sigc::track_obj(Functor2(*pbar4, *pbook4), *pbar4, *pbook4);
result_stream << (*psl2)(0, "Book title: ");
util->check_result(result_stream, "zero, Book title: A Book");
delete pbook4; // auto-disconnect *psl2
pbook4 = nullptr;
result_stream << (*psl2)(0, "Book title: ");
util->check_result(result_stream, "");
delete psl2;
psl2 = nullptr;
delete pbar4;
pbar4 = nullptr;
//C++11 lambda expressions:
// auto-disconnect
// If you want to auto-disconnect a slot with a C++11 lambda expression
// that contains references to sigc::trackable-derived objects, you must use
// sigc::track_obj().
sigc::slot<void, std::ostringstream&> sl10;
{
book guest_book("karl");
// sl1 = [&guest_book](std::ostringstream& stream){ stream << guest_book << "\n"; }; // no auto-disconnect
sl10 = sigc::track_obj([&guest_book](std::ostringstream& stream){ stream << guest_book; }, guest_book);
sl10(result_stream);
util->check_result(result_stream, "karl");
} // auto-disconnect sl10
sl10(result_stream);
util->check_result(result_stream, "");
// auto-disconnect
sigc::slot<void> sl20;
{
book guest_book("karl");
// sl2 = [&guest_book] () { egon(guest_book); }; // no auto-disconnect
// sl2 = std::bind(&egon, std::ref(guest_book)); // does not compile (gcc 4.6.3)
sl20 = sigc::track_obj([&guest_book] () { egon(guest_book); }, guest_book);
sl20();
util->check_result(result_stream, "egon(string 'karl')");
result_stream << static_cast<const std::string&>(guest_book);
util->check_result(result_stream, "egon was here");
} // auto-disconnect sl20
sl20();
util->check_result(result_stream, "");
// Code example in the documentation sigc++/adaptors/macros/track_obj.h.m4
// -----------------------------------------------------------------------
{
//struct bar : public sigc::trackable {} some_bar;
sigc::signal<void> some_signal;
{
bar_group4 some_bar;
//some_signal.connect(sigc::group(&foo, std::ref(some_bar)));
// disconnected automatically if some_bar goes out of scope
//some_signal.connect([&some_bar](){ foo_group4(some_bar); }); // no auto-disconnect
//some_signal.connect(sigc::bind(&foo_group4, std::ref(some_bar))); // auto-disconnects, but we prefer C++11 lambda
some_signal.connect(sigc::track_obj([&some_bar](){ foo_group4(some_bar); }, some_bar));
some_signal.emit();
util->check_result(result_stream, "foo_group4(bar_group4&)");
} // auto-disconnect the lambda expression
some_signal.emit();
util->check_result(result_stream, "");
}
return util->get_result_and_delete_instance() ? EXIT_SUCCESS : EXIT_FAILURE;
}
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