Possible to map an IEnumerable property?

[izzeda]

Great project!

Is it possible to map properties that are an IEnumerable, like a Person that has multiple Pets?

I have an excel file like this, with five columns: one person, with two pets:

FirstName  PetName1  PetAge1  PetName2  PetAge2
John       Napoleon  5        Pebbles   4

and C# Person and Pet classes like this:

public class Person
{
    public string FirstName { get; set; }
    public List<Pet> Pets { get; set; }
 
    public override bool Equals(object obj)
    {
        if (obj is not Person p) return false;
        return p.FirstName == FirstName &&
               p.Pets.Equals(Pets);
    }

    public override int GetHashCode()
    {
        return HashCode.Combine(FirstName, Pets);
    }
}

public class Pet
{
    public string PetName { get; set; }
    public int PetAge { get; set; }

    public override bool Equals(object obj)
    {
        if (obj is not Pet p) return false;
        return p.PetName == PetName &&
               p.PetAge.Equals(PetAge);
    }

    public override int GetHashCode()
    {
        return HashCode.Combine(PetName, PetAge);
    }
}

And a non working test class like this:

public class TestPerson
{
    [SetUp]
    public void Setup()
    {
        Environment.CurrentDirectory = TestContext.CurrentContext.TestDirectory;
    }

    [Test]
    public void FetchPersonWithPets()
    {
        var excel = new ExcelMapper(@"..\..\..\Pets.xlsx") { TrackObjects = true };

        excel.AddMapping<Person>("FirstName", p => p.FirstName);
      
        excel.AddMapping<Pet>("PetName1", p => p.PetName);
        excel.AddMapping<Pet>("PetName2", p => p.PetName);
        excel.AddMapping<Pet>("PetAge1", p => p.PetAge);
        excel.AddMapping<Pet>("PetAge2", p => p.PetAge);

        var persons = excel.Fetch<Person>()
            .ToList();

        var expected = new Person
        {
            FirstName = "John",
            Pets = new List<Pet>
            {
                new() {PetName = "Napoleon", PetAge = 5},
                new() {PetName = "Pebbles", PetAge = 4}
            }
        };
        CollectionAssert.AreEqual(new List<Person> {expected}, persons);
    }
}

Is something like this possible, and am I doing something wrong?
Or is it just not possible?

[mganss]

This is not possible with the current code. If you know the maximum number of pets, you can create that many properties for PetName1 to PetNameN and PetAge1 to PetAgeN, then create an extra adapter property that returns instances of Pet from those properties that are non-null. Another option would be to fetch dynamic objects and map from these to your static objects.

[izzeda]

Thank you for you response and clarification!
I'm going to try that out.