public async Task GoodGetGenericsAsync()
        {
            var enumerator = AsyncEnumerators.GoodGetGenericsAsync <object>();

            while (await enumerator.MoveNextAsync())
            {
            }
        }
        public async Task GoodGetReferencesAsyncWithoutAwait()
        {
            var enumerator = AsyncEnumerators.GoodGetReferencesAsyncWithoutAwait();

            while (await enumerator.MoveNextAsync())
            {
            }
        }
 public Task BadGetGenericsAsync()
 {
     return(Assert.ThrowsExceptionAsync <NullReferenceException>(async() => {
         var enumerator = AsyncEnumerators.BadGetGenericsAsync <object>();
         while (await enumerator.MoveNextAsync())
         {
         }
     }));
 }
 public Task BadGetReferencesAsyncWithoutAwait()
 {
     return(Assert.ThrowsExceptionAsync <NullReferenceException>(async() => {
         var enumerator = AsyncEnumerators.BadGetReferencesAsyncWithoutAwait();
         while (await enumerator.MoveNextAsync())
         {
         }
     }));
 }