id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
12876,BOOST_CHECK_EQUAL fail for vector<int> with operator<< for  vector<T>,401819174@…,Gennadiy Rozental,"#include <boost/test/unit_test.hpp>
#include <iostream>
#include <ostream>
#include <vector>

using namespace std;

class PrintClass
{

};
bool operator== (const PrintClass &l, const PrintClass &r)
{
	std::cout << ""value compare"" << std::endl;
	return false;
}


template <typename T>
std::ostream & operator<< (std::ostream & os, std::vector<T> const &v)
{
	os << ""has "" << &v;
	return os;
}

template <typename T>
bool operator== (const std::vector<T> &l, const std::vector<T> &r)
{
	std::cout << ""const vector compare"" << std::endl;
	return false;
}


BOOST_AUTO_TEST_CASE(test_print_vector_int)
{
	const std::vector<int> a{1};
	const std::vector<int> b{2};

	std::cout << a << std::endl; // work
	BOOST_CHECK_EQUAL(a, b); // don't work.
	// error: static assertion failed: Type has to implement operator<< to be printable

	//std::cout << boost::has_left_shift<std::ostream, vector<int>>::value << endl;

	//  use user define class is ok
	std::vector<PrintClass> c{PrintClass()};
	std::vector<PrintClass> d{PrintClass()};
	std::cout << c << std::endl; // work
	BOOST_CHECK_EQUAL(c, d); //  work
}
",Bugs,closed,To Be Determined,test,Boost 1.61.0,Problem,invalid,,