turtle/doc/example/patterns_static_objects.cpp

// http://turtle.sourceforge.net
//
// Copyright Mathieu Champlon 2015
//
// Distributed under 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)

//[ static_objects_problem
#define BOOST_AUTO_TEST_MAIN
#include <turtle/mock.hpp>
#include <boost/test/auto_unit_test.hpp>
#include <ostream>

namespace {
struct my_class
{
    my_class(int i) : i_(i) {}

    int i_;
};

std::ostream& operator<<(std::ostream& os, const my_class* c)
{
    return os << "my_class " << c->i_; // the 'c' pointer must be valid when logging
}

MOCK_FUNCTION(f, 1, void(my_class*)) // being static 'f' outlive the test case
} // namespace

BOOST_AUTO_TEST_CASE(static_objects_problem)
{
    my_class c(42);
    MOCK_EXPECT(f).once().with(
      &c); // the set expectation will also outlive the test case and leak into other test cases using 'f'
} // the 'c' instance goes out of scope and the '&c' pointer becomes dangling
//]

//[ static_objects_partial_solution
struct fixture
{
    ~fixture()
    {
        mock::reset(); // the use of a fixture ensures the reset will prevent the expectations from leaking into other
                       // test cases
    }
};

BOOST_FIXTURE_TEST_CASE(static_object_partial_solution, fixture)
{
    my_class c(42);
    MOCK_EXPECT(f).once().with(&c);
    f(&c);
    mock::verify(); // verify the expectations before local objects are destroyed and before the fixture resets them
}
//]

//[ static_objects_solution
BOOST_FIXTURE_TEST_CASE(
  static_objects_solution,
  mock::cleanup) // actually the library includes a ready to use fixture just like the one described
{
    my_class c(42);
    MOCK_EXPECT(f).once().with(&c);
    f(&c);
    mock::verify();
}
//]