AsyncNUnit.cs

    [TestFixture]
    public class Test1
    {
        [Test]
        public async Task TestSavesThings()
        {
            var result = await DoSomeAsync();
            Assert.True(result);
        }

        private static Task<bool> DoSomeAsync()
        {
            return Task.Factory.StartNew(
                                      () =>
                                      {
                                          Thread.Sleep(1000);
                                          return true;
                                      });
        }
    }