Unit tests in C++

Question

I'm doing a project in C++ in my University and we need to unit test our classes. The tests are pretty straight-forward - we don't have any "problematic" classes that deal with databases, GUI, web stuff, etc. It's just a command line program.

What is a good unit-testing framework to use that is as simple as possible? Please provide a short example of a test in that framework.

EDIT: I see there are some answers, so I want to add another question: Where do I put the test methods? Are they declared in a different file? Where would that file be? How do I run all tests?

Answer 1

Boost. Hands down.

#define BOOST_TEST_MODULE my_tests // use once per test program
#include <boost/test/unit_test.hpp>

BOOST_AUTO_TEST_CASE( case_x )
{
  ....
  BOOST_CHECK( ... boolean expression ... );
  BOOST_etc...etc...
}

Answer 2

There're many, quite similar. My prefered one is Boost.Test library. It can be complicated if you need but also extremely simple for simple cases. e.g. the simplest possible case looks like:

#include <boost/test/minimal.hpp>

int add( int i, int j ) { return i+j; }

    int test_main( int, char *[] )             // note the name!
    {
        // six ways to detect and report the same error:
        BOOST_CHECK( add( 2,2 ) == 4 );        // #1 continues on error
        BOOST_REQUIRE( add( 2,2 ) == 4 );      // #2 throws on error
        if( add( 2,2 ) != 4 )
          BOOST_ERROR( "Ouch..." );            // #3 continues on error
        if( add( 2,2 ) != 4 )
          BOOST_FAIL( "Ouch..." );             // #4 throws on error
        if( add( 2,2 ) != 4 ) throw "Oops..."; // #5 throws on error

        return add( 2, 2 ) == 4 ? 0 : 1;       // #6 returns error code
    }

This example uses the Minimal Testing Facility.