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Merge with trunk.

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[SVN r44810]
This commit is contained in:
Daniel James
2008-04-27 08:13:25 +00:00
parent aaf9095ed7
commit a38622abe8
2 changed files with 261 additions and 30 deletions
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104
include/boost/optional/optional.hpp
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@ -1,4 +1,4 @@
// Copyright (C) 2003, Fernando Luis Cacciola Carballal.
// Copyright (C) 2003, 2008 Fernando Luis Cacciola Carballal.
//
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@ -9,6 +9,9 @@
// You are welcome to contact the author at:
// fernando_cacciola@hotmail.com
//
// Revisions:
// 25 Apr 2008 (improved swap) Fernando Cacciola, Niels Dekker, Thorsten Ottosen
//
#ifndef BOOST_OPTIONAL_OPTIONAL_FLC_19NOV2002_HPP
#define BOOST_OPTIONAL_OPTIONAL_FLC_19NOV2002_HPP
@ -19,6 +22,7 @@
#include "boost/assert.hpp"
#include "boost/type.hpp"
#include "boost/type_traits/alignment_of.hpp"
#include "boost/type_traits/has_nothrow_constructor.hpp"
#include "boost/type_traits/type_with_alignment.hpp"
#include "boost/type_traits/remove_reference.hpp"
#include "boost/type_traits/is_reference.hpp"
@ -28,6 +32,7 @@
#include "boost/detail/reference_content.hpp"
#include "boost/none.hpp"
#include "boost/utility/compare_pointees.hpp"
#include "boost/utility/in_place_factory.hpp"
#include "boost/optional/optional_fwd.hpp"
@ -571,6 +576,14 @@ class optional : public optional_detail::optional_base<T>
return *this ;
}
void swap( optional & arg )
{
// allow for Koenig lookup
using std::swap ;
swap(*this, arg);
}
// Returns a reference to the value if this is initialized, otherwise,
// the behaviour is UNDEFINED
// No-throw
@ -878,44 +891,77 @@ namespace optional_detail {
#define BOOST_OPTIONAL_STD_SWAP_INTRODUCED_AT_NS_SCOPE
#endif
// optional's swap:
// If both are initialized, calls swap(T&, T&). If this swap throws, both will remain initialized but their values are now unspecified.
// If only one is initialized, calls U.reset(*I), THEN I.reset().
// If U.reset(*I) throws, both are left UNCHANGED (U is kept uinitialized and I is never reset)
// If both are uninitialized, do nothing (no-throw)
template<class T>
inline
void optional_swap ( optional<T>& x, optional<T>& y )
{
if ( !x && !!y )
template<bool use_default_constructor> struct swap_selector;
template<>
struct swap_selector<true>
{
x.reset(*y);
y.reset();
}
else if ( !!x && !y )
{
y.reset(*x);
x.reset();
}
else if ( !!x && !!y )
{
// GCC > 3.2 and all other compilers have the using declaration at function scope (FLC)
template<class T>
static void optional_swap ( optional<T>& x, optional<T>& y )
{
bool hasX = x;
bool hasY = y;
if ( !hasX && !hasY )
return;
if( !hasX )
x = boost::in_place();
else if ( !hasY )
y = boost::in_place();
// GCC > 3.2 and all other compilers have the using declaration at function scope (FLC)
#ifndef BOOST_OPTIONAL_STD_SWAP_INTRODUCED_AT_NS_SCOPE
// allow for Koenig lookup
using std::swap ;
// allow for Koenig lookup
using std::swap ;
#endif
swap(*x,*y);
}
}
swap(*x,*y);
if( !hasX )
y = boost::none ;
else if( !hasY )
x = boost::none ;
}
};
template<>
struct swap_selector<false>
{
template<class T>
static void optional_swap ( optional<T>& x, optional<T>& y )
{
if ( !x && !!y )
{
x = *y;
y = boost::none ;
}
else if ( !!x && !y )
{
y = *x ;
x = boost::none ;
}
else if ( !!x && !!y )
{
// GCC > 3.2 and all other compilers have the using declaration at function scope (FLC)
#ifndef BOOST_OPTIONAL_STD_SWAP_INTRODUCED_AT_NS_SCOPE
// allow for Koenig lookup
using std::swap ;
#endif
swap(*x,*y);
}
}
};
} // namespace optional_detail
template<class T>
struct optional_swap_should_use_default_constructor : has_nothrow_default_constructor<T> {} ;
template<class T> inline void swap ( optional<T>& x, optional<T>& y )
{
optional_detail::optional_swap(x,y);
optional_detail::swap_selector<optional_swap_should_use_default_constructor<T>::value>::optional_swap(x, y);
}
} // namespace boost
#endif

187
test/optional_test.cpp
View File

@ -1,4 +1,4 @@
// Copyright (C) 2003, Fernando Luis Cacciola Carballal.
// Copyright (C) 2003, 2008 Fernando Luis Cacciola Carballal.
//
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@ -9,6 +9,9 @@
// You are welcome to contact the author at:
// fernando_cacciola@hotmail.com
//
// Revisions:
// 25 Apr 2008 (added more swap tests)
//
#include<iostream>
#include<stdexcept>
#include<string>
@ -16,6 +19,8 @@
#define BOOST_ENABLE_ASSERT_HANDLER
#include "boost/bind/apply.hpp" // Included just to test proper interaction with boost::apply<> as reported by Daniel Wallin
#include "boost/mpl/bool.hpp"
#include "boost/mpl/bool_fwd.hpp" // For mpl::true_ and mpl::false_
#include "boost/optional/optional.hpp"
@ -927,6 +932,185 @@ void test_conversions2()
BOOST_CHECK(*get(&opt1) == static_cast<double>(f));
}
namespace optional_swap_test
{
class default_ctor_exception : public std::exception {} ;
class copy_ctor_exception : public std::exception {} ;
class assignment_exception : public std::exception {} ;
//
// Base class for swap test classes. Its assignment should not be called, when swapping
// optional<T> objects. (The default std::swap would do so.)
//
class base_class_with_forbidden_assignment
{
public:
base_class_with_forbidden_assignment & operator=(const base_class_with_forbidden_assignment &)
{
BOOST_CHECK(!"The assignment should not be used while swapping!");
throw assignment_exception();
}
virtual ~base_class_with_forbidden_assignment() {}
};
//
// Class without default constructor
//
class class_without_default_ctor : public base_class_with_forbidden_assignment
{
public:
char data;
explicit class_without_default_ctor(char arg) : data(arg) {}
};
//
// Class whose default constructor should not be used by optional::swap!
//
class class_whose_default_ctor_should_not_be_used : public base_class_with_forbidden_assignment
{
public:
char data;
explicit class_whose_default_ctor_should_not_be_used(char arg) : data(arg) {}
class_whose_default_ctor_should_not_be_used()
{
BOOST_CHECK(!"This default constructor should not be used while swapping!");
throw default_ctor_exception();
}
};
//
// Class whose default constructor should be used by optional::swap.
// Its copy constructor should be avoided!
//
class class_whose_default_ctor_should_be_used : public base_class_with_forbidden_assignment
{
public:
char data;
explicit class_whose_default_ctor_should_be_used(char arg) : data(arg) { }
class_whose_default_ctor_should_be_used() : data('\0') { }
class_whose_default_ctor_should_be_used(const class_whose_default_ctor_should_be_used &)
{
BOOST_CHECK(!"This copy constructor should not be used while swapping!");
throw copy_ctor_exception();
}
};
void swap(class_whose_default_ctor_should_not_be_used & lhs, class_whose_default_ctor_should_not_be_used & rhs)
{
std::swap(lhs.data, rhs.data);
}
void swap(class_whose_default_ctor_should_be_used & lhs, class_whose_default_ctor_should_be_used & rhs)
{
std::swap(lhs.data, rhs.data);
}
void swap(class_without_default_ctor & lhs, class_without_default_ctor & rhs)
{
std::swap(lhs.data, rhs.data);
}
} // End of namespace optional_swap_test.
namespace boost {
//
// Compile time tweaking on whether or not swap should use the default constructor:
//
template <> struct optional_swap_should_use_default_constructor<
::optional_swap_test::class_whose_default_ctor_should_be_used> : mpl::true_ {} ;
template <> struct optional_swap_should_use_default_constructor<
::optional_swap_test::class_whose_default_ctor_should_not_be_used> : mpl::false_ {} ;
}
//
// Tests whether the swap function works properly for optional<T>.
// Assumes that T has one data member, of type char.
// Returns true iff the test is passed.
//
template <class T>
bool test_swap_function( T const* )
{
const boost::unit_test::counter_t counter_before_test = boost::minimal_test::errors_counter();
try
{
optional<T> obj1;
optional<T> obj2('a');
// Test if obj1 and obj2 are properly initialized.
BOOST_CHECK(!obj1);
BOOST_CHECK(!!obj2 && obj2->data == 'a');
// Call non-member swap
swap(obj1, obj2);
// Test if obj1 and obj2 are really swapped
BOOST_CHECK(!!obj1 && obj1->data == 'a');
BOOST_CHECK(!obj2);
}
catch(const std::exception &)
{
// The swap function should not throw, for our test cases.
return false ;
}
return boost::minimal_test::errors_counter() == counter_before_test ;
}
//
// Tests whether the optional<T>::swap member function works properly.
// Assumes that T has one data member, of type char.
// Returns true iff the test is passed.
//
template <class T>
bool test_swap_member_function( T const* )
{
const boost::unit_test::counter_t counter_before_test = boost::minimal_test::errors_counter();
try
{
optional<T> obj1;
optional<T> obj2('a');
// Test if obj1 and obj2 are properly initialized.
BOOST_CHECK(!obj1);
BOOST_CHECK(!!obj2 && obj2->data == 'a');
// Call member swap
obj1.swap(obj2);
// Test if obj1 and obj2 are really swapped
BOOST_CHECK(!!obj1 && obj1->data == 'a');
BOOST_CHECK(!obj2);
}
catch(const std::exception &)
{
// The optional<T>::swap member function should not throw, for our test cases.
return false ;
}
return boost::minimal_test::errors_counter() == counter_before_test ;
}
//
// Tests compile time tweaking of swap, by means of
// optional_swap_should_use_default_constructor.
//
void test_swap_tweaking()
{
BOOST_CHECK( test_swap_function( ARG(optional_swap_test::class_without_default_ctor) ) );
BOOST_CHECK( test_swap_function( ARG(optional_swap_test::class_whose_default_ctor_should_be_used) ) );
BOOST_CHECK( test_swap_function( ARG(optional_swap_test::class_whose_default_ctor_should_not_be_used) ) );
BOOST_CHECK( test_swap_member_function( ARG(optional_swap_test::class_without_default_ctor) ) );
BOOST_CHECK( test_swap_member_function( ARG(optional_swap_test::class_whose_default_ctor_should_be_used) ) );
BOOST_CHECK( test_swap_member_function( ARG(optional_swap_test::class_whose_default_ctor_should_not_be_used) ) );
}
int test_main( int, char* [] )
{
try
@ -936,6 +1120,7 @@ int test_main( int, char* [] )
test_no_implicit_conversions();
test_conversions1();
test_conversions2();
test_swap_tweaking();
}
catch ( ... )
{