Ticket #2243: swap_value_initialized.patch

boost/utility/value_init.hpp

@@ -7 +7 @@
 // 21 Ago 2002 (Created) Fernando Cacciola
 // 24 Dec 2007 (Refactored and worked around various compiler bugs) Fernando Cacciola, Niels Dekker
 // 23 May 2008 (Fixed operator= const issue, added initialized_value) Niels Dekker, Fernando Cacciola
+// 21 Ago 2008 (Added swap) Niels Dekker, Fernando Cacciola
 //
 #ifndef BOOST_UTILITY_VALUE_INIT_21AGO2002_HPP
 #define BOOST_UTILITY_VALUE_INIT_21AGO2002_HPP
@@ -22 +23 @@
 #include <boost/static_assert.hpp>
 #include <boost/type_traits/cv_traits.hpp>
 #include <boost/type_traits/alignment_of.hpp>
+#include <boost/swap.hpp>
 #include <cstring>
 #include <new>
 
@@ -93 +95 @@
       return wrapper_address()->data;
     }
 
+    void swap(value_initialized & arg)
+    {
+      ::boost::swap( this->data(), arg.data() );
+    }
+
     operator T&() const { return this->data(); }
 
 } ;
@@ -110 +117 @@
   return x.data() ;
 }
 
+template<class T>
+void swap ( value_initialized<T> & lhs, value_initialized<T> & rhs )
+{
+  lhs.swap(rhs) ;
+}
 
+
 class initialized_value_t
 {
   public :

libs/utility/value_init_test.cpp

@@ -9 +9 @@
 // 21 Ago 2002 (Created) Fernando Cacciola
 // 15 Jan 2008 (Added tests regarding compiler issues) Fernando Cacciola, Niels Dekker
 // 23 May 2008 (Added tests regarding initialized_value) Niels Dekker
+// 21 Ago 2008 (Added swap test) Niels Dekker
 
 #include <cstring>  // For memcmp.
 #include <iostream>
@@ -181 +182 @@
 };
 
 
+//
+// A struct that allows testing whether its customized swap function is called.
+//
+struct SwapFunctionCallTester
+{
+  bool is_custom_swap_called;
+  int data;
+
+  SwapFunctionCallTester()
+  : is_custom_swap_called(false), data(0) {}
+
+  SwapFunctionCallTester(const SwapFunctionCallTester & arg)
+  : is_custom_swap_called(false), data(arg.data) {}
+
+  void swap(SwapFunctionCallTester & arg)
+  {
+    std::swap(data, arg.data);
+    is_custom_swap_called = true;
+    arg.is_custom_swap_called = true;
+  }
+};
+
+void swap(SwapFunctionCallTester & lhs, SwapFunctionCallTester & rhs)
+{
+  lhs.swap(rhs);
+}
+
+
+
 template<class T>
 void check_initialized_value ( T const& y )
 {
@@ -323 +353 @@
   BOOST_CHECK ( ! get(copyFunctionCallTester3).is_copy_constructed);
   BOOST_CHECK ( get(copyFunctionCallTester3).is_assignment_called);
 
+  boost::value_initialized<SwapFunctionCallTester> swapFunctionCallTester1;
+  boost::value_initialized<SwapFunctionCallTester> swapFunctionCallTester2;
+  get(swapFunctionCallTester1).data = 1;
+  get(swapFunctionCallTester2).data = 2;
+  boost::swap(swapFunctionCallTester1, swapFunctionCallTester2);
+  BOOST_CHECK( get(swapFunctionCallTester1).data == 2 );
+  BOOST_CHECK( get(swapFunctionCallTester2).data == 1 );
+  BOOST_CHECK( get(swapFunctionCallTester1).is_custom_swap_called );
+  BOOST_CHECK( get(swapFunctionCallTester2).is_custom_swap_called );
+
   return 0;
 }
 
 
 unsigned int expected_failures = 0;
 
+