Added swap tests for std types, as discussed at "Re: [boost] [swap] Workaround for ADL failures of MSVC 7.1 and Borland okay?", http://lists.boost.org/Archives/boost/2008/08/140589.php

[SVN r47943]

swap/test/std_string.cpp

@@ -0,0 +1,31 @@
+// Copyright (c) 2008 Joseph Gauterin, Niels Dekker
+//
+// 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)
+
+// Tests swapping std::string objects by means of boost::swap.
+// std::string has its own std::swap overload.
+
+#include <boost/utility/swap.hpp>
+#define BOOST_INCLUDE_MAIN
+#include <boost/test/test_tools.hpp>
+
+#include <string>
+
+int test_main(int, char*[])
+{
+  const std::string initial_value1 = "one";
+  const std::string initial_value2 = "two";
+
+  std::string object1 = initial_value1;
+  std::string object2 = initial_value2;
+
+  boost::swap(object1,object2);
+
+  BOOST_CHECK_EQUAL(object1,initial_value2);
+  BOOST_CHECK_EQUAL(object2,initial_value1);
+
+  return 0;
+}
+