Boost C++ Libraries

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libs/signals/test/ordering_test.cpp

// Boost.Signals library

// Copyright Douglas Gregor 2002-2004. Use, modification and
// distribution is subject to the Boost Software License, Version
// 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)

// For more information, see http://www.boost.org

#include <boost/test/minimal.hpp>
#include <boost/signal.hpp>
#include <iostream>
#include <vector>
#include <algorithm>
#include <cstdlib>
#include <ctime>

std::vector<int> valuesOutput;
bool ungrouped1 = false;
bool ungrouped2 = false;
bool ungrouped3 = false;

struct emit_int {
  emit_int(int v) : value(v) {}

  void operator()() const
  {
    BOOST_TEST(value == 42 || (!ungrouped1 && !ungrouped2 && !ungrouped3));
    valuesOutput.push_back(value);
    std::cout << value << ' ';
  }

private:
  int value;
};

struct write_ungrouped1 {
  void operator()() const
  {
    BOOST_TEST(!ungrouped1);
    ungrouped1 = true;
    std::cout << "(Ungrouped #1)" << ' ';
  }
};

struct write_ungrouped2 {
  void operator()() const
  {
    BOOST_TEST(!ungrouped2);
    ungrouped2 = true;
    std::cout << "(Ungrouped #2)" << ' ';
  }
};

struct write_ungrouped3 {
  void operator()() const
  {
    BOOST_TEST(!ungrouped3);
    ungrouped3 = true;
    std::cout << "(Ungrouped #3)" << ' ';
  }
};

int test_main(int, char* [])
{
  using namespace std;
  srand(time(0));

  std::vector<int> sortedValues;

  boost::signal0<void> sig;
  sig.connect(write_ungrouped1());
  for (int i = 0; i < 100; ++i) {
#ifdef BOOST_NO_STDC_NAMESPACE
    int v = rand() % 100;
#else
    int v = std::rand() % 100;
#endif
    sortedValues.push_back(v);
    sig.connect(v, emit_int(v));

    if (i == 50) {
      sig.connect(write_ungrouped2());
    }
  }
  sig.connect(write_ungrouped3());

  std::sort(sortedValues.begin(), sortedValues.end());

  // 17 at beginning, 42 at end
  sortedValues.insert(sortedValues.begin(), 17);
  sig.connect(emit_int(17), boost::BOOST_SIGNALS_NAMESPACE::at_front);
  sortedValues.push_back(42);
  sig.connect(emit_int(42));

  sig();
  std::cout << std::endl;

  BOOST_TEST(valuesOutput == sortedValues);
  BOOST_TEST(ungrouped1);
  BOOST_TEST(ungrouped2);
  BOOST_TEST(ungrouped3);
  return 0;
}