public async Task UpdateAutoWithOptimisticConcurrencyTest() { var auto = await _target.GetByIdAsync(new GetAutoByIdRequest { Id = 1 }); var auto2 = auto; auto.Tagestarif = 100; auto2.Tagestarif = 200; await _target.UpdateAsync(auto); Assert.Throws <RpcException>(() => _target.Update(auto2)); }