Use buffers_to_string in tests

fix #782

test/beast/core/ostream.cpp

@@ -10,6 +10,7 @@
 // Test that header file is self-contained.
 #include <boost/beast/core/ostream.hpp>
 
+#include <boost/beast/core/buffers_to_string.hpp>
 #include <boost/beast/core/multi_buffer.hpp>
 #include <boost/beast/unit_test/suite.hpp>
 #include <ostream>
@@ -20,19 +21,6 @@ namespace beast {
 class ostream_test : public beast::unit_test::suite
 {
 public:
-    template<class ConstBufferSequence>
-    static
-    std::string
-    to_string(ConstBufferSequence const& bs)
-    {
-        std::string s;
-        s.reserve(buffer_size(bs));
-        for(auto b : beast::detail::buffers_range(bs))
-            s.append(reinterpret_cast<
-                char const*>(b.data()), b.size());
-        return s;
-    }
-
     void
     run() override
     {
@@ -41,7 +29,7 @@ public:
             auto os = ostream(b);
             os << "Hello, world!\n";
             os.flush();
-            BEAST_EXPECT(to_string(b.data()) == "Hello, world!\n");
+            BEAST_EXPECT(buffers_to_string(b.data()) == "Hello, world!\n");
             auto os2 = std::move(os);
         }
         {
@@ -56,7 +44,7 @@ public:
                 "0123456789abcdef" "0123456789abcdef" "0123456789abcdef" "0123456789abcdef";
             multi_buffer b;
             ostream(b) << s;
-            BEAST_EXPECT(to_string(b.data()) == s);
+            BEAST_EXPECT(buffers_to_string(b.data()) == s);
         }
     }
 };