turtle/doc/example/reference.cpp

// http://turtle.sourceforge.net
//
// Copyright Mathieu Champlon 2014
//
// 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)

#include <boost/test/auto_unit_test.hpp>
#include <turtle/mock.hpp>

namespace class_example_1
{
//[ class_example_1
MOCK_CLASS( mock_class )
{};

BOOST_AUTO_TEST_CASE( demonstrates_instantiating_a_mock_class )
{
    mock_class c;
}
//]
}

namespace class_example_2
{
//[ class_example_2
template< typename T >
MOCK_CLASS( mock_class )
{};

BOOST_AUTO_TEST_CASE( demonstrates_instantiating_a_template_mock_class )
{
    mock_class< int > c;
}
//]
}

namespace class_example_3
{
//[ class_example_3
struct base_class
{};

MOCK_BASE_CLASS( mock_class, base_class )
{};

BOOST_AUTO_TEST_CASE( demonstrates_instantiating_a_derived_mock_class )
{
    mock_class c;
}
//]
}

namespace class_example_4
{
//[ class_example_4
template< typename T >
struct base_class
{};

template< typename T >
MOCK_BASE_CLASS( mock_class, base_class< T > )
{};

BOOST_AUTO_TEST_CASE( demonstrates_instantiating_a_template_derived_mock_class )
{
    mock_class< int > c;
}
//]
}

namespace class_example_5
{
//[ class_example_5
struct name : mock::object // equivalent to using MOCK_CLASS
{};
//]
}

namespace class_example_6
{
//[ class_example_6
template< typename T >
struct name : mock::object // equivalent to using MOCK_CLASS
{};
//]
}

namespace class_example_7
{
//[ class_example_7
class base
{};

struct name : base, mock::object // equivalent to using MOCK_BASE_CLASS
{
    typedef base base_type;      // this is required for the shortest form of MOCK_METHOD to work when not using MOCK_BASE_CLASS
};
//]
}

namespace class_example_8
{
//[ class_example_8
template< typename T >
struct base
{};

template< typename T >
struct name : base< T >, mock::object
{
    typedef base< T > base_type;
};
//]
}

namespace member_function_example_1
{
//[ member_function_example_1
struct base_class
{
    virtual ~base_class() = default;
    virtual void method( int ) = 0;
};

MOCK_BASE_CLASS( mock_class, base_class )
{
    MOCK_METHOD( method, 1 )              // only possible when referring unambiguously to a base class method
};
//]
}

namespace member_function_example_2
{
//[ member_function_example_2
struct base_class
{
    virtual ~base_class() = default;
    virtual void method( int, const std::string& ) = 0;
    virtual void method( float ) = 0;
};

MOCK_BASE_CLASS( mock_class, base_class )
{
    MOCK_METHOD( method, 2, void( int, const std::string& ), identifier_1 ) // both the signature and identifier must be specified because of ambiguity due to overloading
    MOCK_METHOD( method, 1, void( float ), identifier_2 )                   // the identifier must differ from the previous one in order to fully disambiguate methods
};
//]
}

namespace member_function_example_3
{
//[ member_function_example_3
struct base_class
{
    virtual ~base_class() = default;
    virtual void method( float ) = 0;
    virtual void method( float ) const = 0;
};

MOCK_BASE_CLASS( mock_class, base_class )
{
    MOCK_METHOD( method, 1, void( float ) ) // this generates both const and non-const versions
};
//]
}

namespace member_function_example_4
{
//[ member_function_example_4
struct base_class
{
    virtual ~base_class() = default;
    virtual void method( float ) = 0;
    virtual void method( float ) const = 0;
};

MOCK_BASE_CLASS( mock_class, base_class )
{
    MOCK_CONST_METHOD( method, 1, void( float ), identifier_1 )     // this generates only the const version
    MOCK_NON_CONST_METHOD( method, 1, void( float ), identifier_2 ) // this generates only the non-const version, with a different identifier
};
//]
}

namespace member_function_example_5
{
//[ member_function_example_5
struct base_class
{
    virtual ~base_class() = default;
    virtual void method( float ) = 0;
};

struct mock_class : base_class
{
    typedef base_class base_type; // this is required for MOCK_METHOD to work when not using MOCK_BASE_CLASS

    MOCK_METHOD( method, 1 )
};
//]
}

namespace member_function_example_6
{
//[ member_function_example_6
MOCK_CLASS( mock_class )
{
    MOCK_NON_CONST_METHOD( operator=, 1, mock_class&( const mock_class& ), assignment ) // operators require a custom identifier
};
//]
}

namespace member_function_example_7
{
//[ member_function_example_7
template< typename T >
MOCK_CLASS( mock_class )
{
    MOCK_METHOD_TPL( method, 1, void( const T& ) ) // the _TPL variants must be used if the signature includes a template parameter of the class
};
//]
}

namespace member_function_example_8
{
//[ member_function_example_8
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 0, BOOST_IDENTITY_TYPE((std::map< int, int >())) ) // the signature must be wrapped in BOOST_IDENTITY_TYPE if the return type contains a comma
};
//]
}

#ifdef BOOST_MSVC
namespace member_function_example_9
{
//[ member_function_example_9
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( __stdcall method, 0, void(), method ) // all parameters must be provided when specifying a different calling convention
};
//]
}
#endif

namespace static_member_function_example_1
{
//[ static_member_function_example_1
MOCK_CLASS( mock_class )
{
    MOCK_STATIC_METHOD( method, 1, float( int ) )
};
//]
}

namespace static_member_function_example_2
{
//[ static_member_function_example_2
template< typename T >
MOCK_CLASS( mock_class )
{
    MOCK_STATIC_METHOD_TPL( method, 1, void( T ) )
};
//]
}

#ifdef BOOST_MSVC
namespace static_member_function_example_3
{
//[ static_member_function_example_3
MOCK_CLASS( mock_class )
{
    MOCK_STATIC_METHOD( __stdcall method, 0, void(), method ) // all parameters must be provided when specifying a different calling convention
};
//]
}
#endif

namespace constructor_example_1
{
//[ constructor_example_1
MOCK_CLASS( mock_class )
{
    MOCK_CONSTRUCTOR( mock_class, 2, ( int, const std::string& ), identifier )
};
//]
}

namespace constructor_example_2
{
//[ constructor_example_2
template< typename T >
MOCK_CLASS( mock_class )
{
    MOCK_CONSTRUCTOR( mock_class, 2, ( int, const std::string& ), identifier )
    MOCK_CONSTRUCTOR_TPL( mock_class, 2, ( T, const std::string& ), identifier_2 )
};
//]
}

#ifdef BOOST_MSVC
namespace constructor_example_3
{
//[ constructor_example_3
MOCK_CLASS( mock_class )
{
    MOCK_CONSTRUCTOR( __stdcall mock_class, 0, (), constructor )
};
//]
}
#endif

namespace destructor_example_1
{
//[ destructor_example_1
MOCK_CLASS( mock_class )
{
    MOCK_DESTRUCTOR( ~mock_class, destructor )
};
//]
}

#ifdef BOOST_MSVC
namespace destructor_example_2
{
//[ destructor_example_2
MOCK_CLASS( mock_class )
{
    MOCK_DESTRUCTOR( __stdcall ~mock_class, destructor )
};
//]
}
#endif

namespace conversion_operator_example_1
{
//[ conversion_operator_example_1
MOCK_CLASS( mock_class )
{
    MOCK_CONVERSION_OPERATOR( operator, int, conversion_to_int )
    MOCK_CONST_CONVERSION_OPERATOR( operator, const std::string&, conversion_to_string )
};
//]
}

namespace conversion_operator_example_2
{
//[ conversion_operator_example_2
template< typename T >
MOCK_CLASS( mock_class )
{
    MOCK_CONVERSION_OPERATOR_TPL( operator, T, conversion_to_T )                                       // the _TPL variants must be used if the signature includes a template parameter of the class
    MOCK_CONST_CONVERSION_OPERATOR( operator, const std::string&, const_conversion_to_string )
    MOCK_NON_CONST_CONVERSION_OPERATOR( operator, const std::string&, non_const_conversion_to_string )
};
//]
}

#ifdef BOOST_MSVC
namespace conversion_operator_example_3
{
//[ conversion_operator_example_3
MOCK_CLASS( mock_class )
{
    MOCK_CONVERSION_OPERATOR( __stdcall operator, int, conversion_to_int )
};
//]
}
#endif

namespace function_example_1
{
//[ function_example_1
MOCK_FUNCTION( f, 1, void( int ) )

BOOST_AUTO_TEST_CASE( demonstrates_instantiating_a_mock_function )
{
    MOCK_EXPECT(f).once().with(3);
    f( 3 );
}
//]
}

#ifdef BOOST_MSVC
namespace function_example_2
{
//[ function_example_2
MOCK_FUNCTION( __stdcall f, 0, void(), f ) // all parameters must be provided when specifying a different calling convention
//]
}
#endif

namespace functor_example_1
{
//[ functor_example_1
BOOST_AUTO_TEST_CASE( demonstrates_instantiating_a_mock_functor )
{
   MOCK_FUNCTOR( f, void( int ) );
   MOCK_EXPECT(f).once().with(3);
   f( 3 );
}
//]
}

namespace functor_example_2
{
//[ functor_example_2
template< typename T >
struct mock_class
{
    MOCK_FUNCTOR( f, void( T ) );
};

BOOST_AUTO_TEST_CASE( demonstrates_instantiating_a_mock_functor_inside_a_class )
{
    mock_class< int > c;
    MOCK_EXPECT(c.f).once().with(3);
    c.f( 3 );
}
//]
}

namespace expectation_example_1
{
//[ expectation_example_1
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 1, int( int ), method )
    MOCK_METHOD( method, 2, void( const std::string&, float ), method2 )
};

BOOST_AUTO_TEST_CASE( demonstrates_configuring_mock_objects )
{
    mock_class c;
    mock::sequence s;
    MOCK_EXPECT( c.method ).once().with( 0 ).in( s ).returns( 42 );
    MOCK_EXPECT( c.method2 ).never().with( "ok", mock::any );
    MOCK_EXPECT( c.method2 ).at_least( 2 ).in( s ).throws( std::runtime_error( "error !" ) );
    BOOST_CHECK(c.method(0) == 42);
    BOOST_CHECK_THROW(c.method("notok", 1.f), std::runtime_error);
    BOOST_CHECK_THROW(c.method("notok", 2.f), std::runtime_error);
}
//]
}

namespace invocation_example_1
{
//[ invocation_example_1
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 2, void( int, const std::string& ) )
    MOCK_METHOD( method2, 1, void( int ) )
};

BOOST_AUTO_TEST_CASE( demonstrates_setting_up_invocations_on_a_mock_method )
{
    mock_class c;
    MOCK_EXPECT( c.method ).once(); // can only be called once
    MOCK_EXPECT( c.method2 );        // can be called an unlimited number of times
    c.method(42, "Hello world!");
    c.method2(42);
    c.method2(42);
    c.method2(42);
}
//]
}

namespace invocation_example_2
{
//[ invocation_example_2
BOOST_AUTO_TEST_CASE( demonstrates_setting_up_an_invocation_on_a_mock_functor )
{
    MOCK_FUNCTOR( f, void( int, const std::string& ) );
    MOCK_EXPECT( f ).once();
    f(42, "Hello world!");
}
//]
}

namespace invocation_example_3
{
//[ invocation_example_3
MOCK_FUNCTION( f, 1, void( int ) )

BOOST_AUTO_TEST_CASE( demonstrates_setting_up_an_invocation_on_a_mock_function )
{
    MOCK_EXPECT( f ).once();
    f(42);
}
//]
}

namespace invocation_example_4
{
//[ invocation_example_4
MOCK_CLASS( mock_class )
{
    MOCK_STATIC_METHOD( method1, 1, void( int ) )
    MOCK_STATIC_METHOD( method2, 1, void( int ) )
};

BOOST_AUTO_TEST_CASE( demonstrates_setting_up_an_invocation_on_a_mock_static_method )
{
    mock_class c;
    MOCK_EXPECT( c.method1 ).once();
    MOCK_EXPECT( mock_class::method2 ).once(); // does the same
    c.method1(42);
    c.method2(42);
}
//]
}

namespace constraints_example_1
{
//[ constraints_example_1
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method1, 2, void( int, const std::string& ) )
    MOCK_METHOD( method2, 2, void( int, const std::string& ) )
};

BOOST_AUTO_TEST_CASE( demonstrates_adding_builtin_constraints )
{
   mock_class c;
   MOCK_EXPECT( c.method1 ).with( mock::equal( 3 ), mock::equal( "some string" ) );
   MOCK_EXPECT( c.method2 ).with( 3, "some string" );                               // equivalent to the previous one using short-cuts
   c.method1(3, "some string");
   c.method2(3, "some string");
}
//]
}

namespace constraints_example_2
{
//[ constraints_example_2
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 1, void( int ) )
};

bool custom_constraint( int actual )
{
   return actual == 42;
}

BOOST_AUTO_TEST_CASE( demonstrates_adding_a_custom_constraint_with_a_free_function )
{
   mock_class c;
   MOCK_EXPECT( c.method ).with( &custom_constraint );
   c.method(42);
}
//]
}

namespace constraints_example_3
{
//[ constraints_example_3
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 1, void( int ) )
};

bool custom_constraint( int expected, int actual )
{
   return expected == actual;
}

BOOST_AUTO_TEST_CASE( demonstrates_adding_a_custom_constraint_with_a_standard_library_functor )
{
   mock_class c;
   MOCK_EXPECT( c.method ).with( std::bind1st( std::ptr_fun( &custom_constraint ), 42 ) ); // std::ptr_fun creates an std::unary_function
   c.method(42);
}
//]
}

namespace constraints_example_4
{
//[ constraints_example_4
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 1, void( int ) )
};

bool custom_constraint( int expected, int actual )
{
   return expected == actual;
}

BOOST_AUTO_TEST_CASE( demonstrates_adding_a_custom_constraint_with_std_bind )
{
   mock_class c;
   using namespace std::placeholders;
   MOCK_EXPECT( c.method ).with( std::bind( &custom_constraint, 42, _1 ) );
   c.method(42);
}
//]
}

#ifndef BOOST_MSVC // this produces an ICE with all versions of MSVC

#include <boost/lambda/lambda.hpp>

namespace constraints_example_5
{
//[ constraints_example_5
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 1, void( int ) )
};

BOOST_AUTO_TEST_CASE( demonstrates_adding_a_custom_constraint_with_boost_lambda )
{
   mock_class c;
   MOCK_EXPECT( c.method ).with( boost::lambda::_1 == 42 );
   c.method(42);
}
//]
}

#endif // BOOST_MSVC

#include <boost/phoenix/phoenix.hpp>

namespace constraints_example_6
{
//[ constraints_example_6
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method1, 1, void( int ) )
    MOCK_METHOD( method2, 1, void( int ) )
};

BOOST_AUTO_TEST_CASE( demonstrates_adding_a_custom_constraint_with_boost_phoenix )
{
   mock_class c;
   MOCK_EXPECT( c.method1 ).with( boost::phoenix::arg_names::arg1 == 42 );
   MOCK_EXPECT( c.method2 ).with( boost::phoenix::arg_names::_1 == 42 );
   c.method1(42);
   c.method2(42);
}
//]
}

namespace constraints_example_7
{
//[ constraints_example_7
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 1, void( int ) )
};

BOOST_AUTO_TEST_CASE( demonstrates_adding_a_constraint_with_cxx11_lambda )
{
    mock_class c;
    MOCK_EXPECT( c.method ).with( []( int actual ) { return 42 == actual; } );
    c.method(42);
}
//]
}

namespace constraints_example_8
{
//[ constraints_example_8
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 2, void( int, const std::string& ) )
};

BOOST_AUTO_TEST_CASE( demonstrates_combining_constraints )
{
   mock_class c;
   MOCK_EXPECT( c.method ).with( mock::less( 4 ) && mock::greater( 2 ), ! mock::equal( "" ) );
   c.method(3, "Hello World!");
}
//]
}

namespace constraints_example_9
{
//[ constraints_example_9
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 2, void( const std::string&, std::size_t ) )
};

bool custom_constraint( const std::string& actual_1, std::size_t actual_2 )
{
    return actual_1.size() <= actual_2;
}

BOOST_AUTO_TEST_CASE( demonstrates_one_constraint_for_all_arguments )
{
   mock_class c;
   MOCK_EXPECT( c.method ).with( &custom_constraint );
   c.method("1234", 4);
}
//]
}

namespace sequence_example_1
{
//[ sequence_example_1
MOCK_CLASS( mock_class_1 )
{
    MOCK_METHOD( method_1, 0, void() )
};

MOCK_CLASS( mock_class_2 )
{
    MOCK_METHOD( method_2, 0, void() )
};

MOCK_CLASS( mock_class_3 )
{
    MOCK_METHOD( method_3, 0, void() )
};

BOOST_AUTO_TEST_CASE( demonstrates_enforcing_several_expectation_orders )
{
   mock_class_1 c_1;
   mock_class_2 c_2;
   mock_class_3 c_3;
   mock::sequence s_1, s_2;
   MOCK_EXPECT( c_1.method_1 ).in( s_1 );
   MOCK_EXPECT( c_2.method_2 ).in( s_2 );      // c_1.method_1 and c_2.method_2 are in different sequences and can be called in any order
   MOCK_EXPECT( c_3.method_3 ).in( s_1, s_2 ); // c_3.method_3 must be called after both c_1.method_1 and c_2.method_2
   c_2.method_2();
   c_1.method_1();
   c_3.method_3();
}
//]
}

namespace action_example_1
{
//[ action_example_1
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 1, int( int ) )
};

int function( int i )
{
    return i;
}

BOOST_AUTO_TEST_CASE( demonstrates_configuring_actions )
{
   mock_class c;
   MOCK_EXPECT( c.method ).once().returns( 42 );
   MOCK_EXPECT( c.method ).once().moves( 42 );                               // returns by moving the value
   MOCK_EXPECT( c.method ).once().throws( std::runtime_error( "error !" ) );
   MOCK_EXPECT( c.method ).once().calls( &function );                        // forwards 'method' parameter to 'function'
   MOCK_EXPECT( c.method ).once().calls( std::bind( &function, 42 ) );     // drops 'method' parameter and binds 42 as parameter to 'function'
   MOCK_EXPECT( c.method ).once().calls( []( int i ) { return i; } );        // uses a C++11 lambda
   BOOST_CHECK(c.method(0) == 42);
   BOOST_CHECK(c.method(1) == 42);
   BOOST_CHECK_THROW(c.method(0), std::runtime_error);
   BOOST_CHECK(c.method(2) == 2);
   BOOST_CHECK(c.method(3) == 42);
   BOOST_CHECK(c.method(4) == 4);
}
//]
}

namespace action_example_2
{
//[ action_example_2
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 0, int&() )
};

BOOST_AUTO_TEST_CASE( demonstrates_configuring_actions_with_references )
{
   mock_class c;
   int i = 0;
   MOCK_EXPECT( c.method ).returns( std::ref( i ) ); // wrap i to store a reference
   c.method() = 42;                                    // really change i and not just the stored copy
   BOOST_CHECK_EQUAL( 42, i );                         // indeed
}
//]
}

namespace verification_example_1
{
//[ verification_example_1
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 0, void() )
};

BOOST_AUTO_TEST_CASE( demonstrates_verifying_a_mock_method )
{
   mock_class c;
   MOCK_VERIFY( c.method ); // logs an error and returns false if not all expectations are met
   mock::verify( c );       // verifies all expectations set for all methods of 'c'
   mock::verify();          // verifies all existing mock objects, functions and functors
}
//]
}

namespace verification_example_2
{
//[ verification_example_2
BOOST_AUTO_TEST_CASE( demonstrates_verifying_a_mock_functor )
{
   MOCK_FUNCTOR( f, void( int ) );
   MOCK_VERIFY( f );               // logs an error and returns false if not all expectations are met
   mock::verify( f );              // behaves the same as MOCK_VERIFY
   mock::verify();                 // verifies all existing mock objects, functions and functors
}
//]
}

namespace verification_example_3
{
//[ verification_example_3
MOCK_FUNCTION( f, 1, void( int ) )

BOOST_AUTO_TEST_CASE( demonstrates_verifying_a_mock_function )
{
   MOCK_VERIFY( f ); // logs an error and returns false if not all expectations are met
   mock::verify();   // verifies all existing mock objects, functions and functors
}
//]
}

namespace verification_example_4
{
//[ verification_example_4
MOCK_CLASS( mock_class )
{
    MOCK_STATIC_METHOD( method, 0, void() )
};

BOOST_AUTO_TEST_CASE( demonstrates_verifying_a_static_mock_method )
{
   mock_class c;
   MOCK_VERIFY( c.method );           // logs an error and returns false if not all expectations are met
   MOCK_VERIFY( mock_class::method ); // does the same
   mock::verify();                    // verifies all existing mock objects, functions and functors
}
//]
}

namespace reset_example_1
{
//[ reset_example_1
MOCK_CLASS( mock_class )
{
    MOCK_METHOD( method, 0, void() )
};

BOOST_AUTO_TEST_CASE( demonstrates_resetting_a_mock_method )
{
   mock_class c;
   MOCK_RESET( c.method ); // resets all expectations set for 'c.method'
   mock::reset( c );       // resets all expectations set on 'c'
   mock::reset();          // resets all existing mock objects, functions and functors
}
//]
}

namespace reset_example_2
{
//[ reset_example_2
BOOST_AUTO_TEST_CASE( demonstrates_resetting_a_mock_functor )
{
   MOCK_FUNCTOR( f, void( int ) );
   MOCK_RESET( f );                // resets all expectations set for 'f'
   mock::reset( f );               // behaves the same as MOCK_RESET
   mock::reset();                  // resets all existing mock objects, functions and functors
}
//]
}

namespace reset_example_3
{
//[ reset_example_3
MOCK_FUNCTION( f, 1, void( int ) )

BOOST_AUTO_TEST_CASE( demonstrates_resetting_a_mock_function )
{
   MOCK_RESET( f ); // resets all expectations set for 'f'
   mock::reset();   // resets all existing mock objects, functions and functors
}
//]
}

namespace reset_example_4
{
//[ reset_example_4
MOCK_CLASS( mock_class )
{
    MOCK_STATIC_METHOD( method, 0, void() )
};

BOOST_AUTO_TEST_CASE( demonstrates_resetting_a_static_mock_method )
{
   mock_class c;
   MOCK_RESET( c.method );           // resets all expectations set for 'c::method'
   MOCK_RESET( mock_class::method ); // resets all expectations set for 'c::method'
   mock::reset();                    // resets all existing mock objects, functions and functors
}
//]
}

namespace helpers_example_1
{
//[ helpers_example_1
MOCK_CONSTRAINT( any, true )               // this is how mock::any could be defined
MOCK_CONSTRAINT( forty_two, actual == 42 ) // this defines a 'forty_two' constraint

BOOST_AUTO_TEST_CASE( mock_constraint_0_arity )
{
    MOCK_FUNCTOR( f, void( int ) );
    MOCK_EXPECT( f ).with( forty_two );
    MOCK_EXPECT( f ).with( any );
}
//]
}

namespace helpers_example_2
{
//[ helpers_example_2
MOCK_CONSTRAINT( equal, expected, actual == expected )                  // this is how mock::equal could be defined
MOCK_CONSTRAINT( near, expected, std::abs( actual - expected ) < 0.01 ) // this defines a 'near' constraint which can be used as 'near( 42 )'

BOOST_AUTO_TEST_CASE( mock_constraint_1_arity )
{
    MOCK_FUNCTOR( f, void( int ) );
    MOCK_EXPECT( f ).with( near( 42 ) );
    MOCK_EXPECT( f ).with( equal( 42 ) );
}
//]
}

namespace helpers_example_3
{
//[ helpers_example_3
MOCK_CONSTRAINT( near, expected, tolerance, std::abs( actual - expected ) < tolerance ) // this is how mock::near could be defined

BOOST_AUTO_TEST_CASE( mock_constraint_2_arity )
{
    MOCK_FUNCTOR( f, void( int ) );
    MOCK_EXPECT( f ).with( near( 42, 0.001 ) );
}
//]
}