While trying out HippoMocks (Cygwin, GCC 4.5.3, CppUnit) to mock an interface, one of the methods is causing compilation to fail. Further triage shows that only mocking methods with std::vector as arguments would fail.
e.g.
m_Mocks.ExpectCall(m_EmpSvcMock.get(), IEmployeeServiceProxy::GetEmployees); // compile error!
m_Mocks.ExpectCall(m_EmpSvcMock.get(), IEmployeeServiceProxy::AddEmployee); // compile OK!
where
class IEmployeeServiceProxy
{
public:
virtual ~IEmployeeServiceProxy() { }
virtual void AddEmployee(const Employee&) = 0;
virtual void GetEmployees(std::vector<Employee>&) = 0;
};
struct Employee
{
boost::uuids::uuid Id;
std::string Name;
};
Compiler error:
/usr/lib/gcc/i686-pc-cygwin/4.5.3/include/c++/bits/stream_iterator.h: In member function ‘std::ostream_iterator<_Tp, _CharT, _Traits>& std::ostream_iterator<_Tp, _CharT, _Traits>::operator=(const _Tp&) [with _Tp = EmployeeServiceLib::Employee, _CharT = char, _Traits = std::char_traits<char>, std::ostream_iterator<_Tp, _CharT, _Traits> = std::ostream_iterator<EmployeeServiceLib::Employee, char, std::char_traits<char> >]’:
In file included from /usr/lib/gcc/i686-pc-cygwin/4.5.3/include/c++/iterator:67:0,
from /usr/include/boost/uuid/string_generator.hpp:14,
from /usr/include/boost/uuid/uuid_generators.hpp:15,
from tests/../../RcfTestShared/IEmployeeService.hpp:7,
from tests/../IEmployeeServiceProxy.h:11,
from tests/ClientTest.h:13,
from tests/ClientTest.cpp:8:
/usr/lib/gcc/i686-pc-cygwin/4.5.3/include/c++/bits/stl_algobase.h:349:8: instantiated from ‘static _OI std::__copy_move<false, false, std::random_access_iterator_tag>::__copy_m(_II, _II, _OI) [with _II = const EmployeeServiceLib::Employee*, _OI = std::ostream_iterator<EmployeeServiceLib::Employee, char, std::char_traits<char> >]’
/usr/lib/gcc/i686-pc-cygwin/4.5.3/include/c++/bits/stl_algobase.h:404:70: instantiated from ‘_OI std::__copy_move_a(_II, _II, _OI) [with bool _IsMove = false, _II = const EmployeeServiceLib::Employee*, _OI = std::ostream_iterator<EmployeeServiceLib::Employee, char, std::char_traits<char> >]’
/usr/lib/gcc/i686-pc-cygwin/4.5.3/include/c++/bits/stl_algobase.h:442:39: instantiated from ‘_OI std::__copy_move_a2(_II, _II, _OI) [with bool _IsMove = false, _II = __gnu_cxx::__normal_iterator<const EmployeeServiceLib::Employee*, std::vector<EmployeeServiceLib::Employee> >, _OI = std::ostream_iterator<EmployeeServiceLib::Employee, char, std::char_traits<char> >]’
/usr/lib/gcc/i686-pc-cygwin/4.5.3/include/c++/bits/stl_algobase.h:474:18: instantiated from ‘_OI std::copy(_II, _II, _OI) [with _II = __gnu_cxx::__normal_iterator<const EmployeeServiceLib::Employee*, std::vector<EmployeeServiceLib::Employee> >, _OI = std::ostream_iterator<EmployeeServiceLib::Employee, char, std::char_traits<char> >]’
../../RCF/RCF-1.3.1/include/RCF/Tools.hpp:116:9: instantiated from ‘std::ostream& std::operator<<(std::ostream&, const std::vector<_RealType>&) [with T = EmployeeServiceLib::Employee, std::ostream = std::basic_ostream<char>]’
../../hippomocks/HippoMocks/hippomocks.h:94:5: instantiated from ‘static void printArg<T>::print(std::ostream&, T, bool) [with T = std::vector<EmployeeServiceLib::Employee>&, std::ostream = std::basic_ostream<char>]’
../../hippomocks/HippoMocks/hippomocks.h:170:5: instantiated from ‘void ref_tuple<A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P>::printTo(std::ostream&) const [with A = std::vector<EmployeeServiceLib::Employee>&, B = NullType, C = NullType, D = NullType, E = NullType, F = NullType, G = NullType, H = NullType, I = NullType, J = NullType, K = NullType, L = NullType, M = NullType, N = NullType, O = NullType, P = NullType, std::ostream = std::basic_ostream<char>]’
tests/ClientTest.cpp:47:1: instantiated from here
/usr/lib/gcc/i686-pc-cygwin/4.5.3/include/c++/bits/stream_iterator.h:196:2: error: cannot bind ‘std::ostream_iterator<EmployeeServiceLib::Employee, char, std::char_traits<char> >::ostream_type’ lvalue to ‘std::basic_ostream<char>&&’
/usr/lib/gcc/i686-pc-cygwin/4.5.3/include/c++/ostream:579:5: error: initializing argument 1 of ‘std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&&, const _Tp&) [with _CharT = char, _Traits = std::char_traits<char>, _Tp = EmployeeServiceLib::Employee]’
Possibly it's complaining that you don't have operator<< defined for Employee, but I'm not certain. I think you've missed the last line of your error messages? In any case I would read the documentation and see what requirements they have for the class being tested.
Requiring you to define operator== and operator<< and maybe others is pretty standard for a unit testing framework. If you think about it a unit testing framework is going to need to compare objects of the types you are testing and maybe going to try and output those objects when things go wrong.