public void CopyToAsync_Invalid()
 {
     var sc = new StringContent ("");
     try {
         sc.CopyToAsync (null);
         Assert.Fail ("#1");
     } catch (ArgumentNullException) {
     }
 }
        public void CopyToAsync()
        {
            var sc = new StringContent ("gt");

            var dest = new MemoryStream ();
            var task = sc.CopyToAsync (dest);
            task.Wait ();
            Assert.AreEqual (2, dest.Length, "#1");
        }