public async Task Can_Get_AvailableOptions()
{
//Arrange
var input = await PrepareFullRelationAsync(true, true, true);
//Act
var options = await SystemRelationHelper.GetAvailableOptionsAsync(input.FromUsageId, input.ToUsageId);
//Assert
Assert.NotNull(options);
var interfaceDTO = Assert.Single(options.AvailableInterfaces);
Assert.Equal(input.InterfaceId.Value, interfaceDTO.Id);
Assert.Contains(options.AvailableContracts.Select(x => x.Id), x => x == input.ContractId);
Assert.Contains(options.AvailableFrequencyTypes.Select(x => x.Id), x => x == input.FrequencyTypeId);
}