PersistenceSpecification CheckList with Private property

Question

I'm trying to test a private list via the CheckList method in PersistenceSpecification. But I'm not quite getting there. Could anyone help please?

Entity:

public class Item: Entity<int>
{
    //values in list are used in later (internal) calculations
    private readonly IList<PurchaseInfo> _purchaseInfo = new List<PurchaseInfo>();
    public virtual string SupplierCode {get; set;}
}

Map:

   public class ItemMap: ClassMap<Item>
   {
       public ItemMap()
       {
           Table("ITEM");

           Id(u => u.Id).Column("ITEMNR").GeneratedBy.Assigned(); 
           Map(u => I.SupplierCode).Column("SUPPLIERNR");
           HasMany<PurchaseInfo>(Reveal.Member<Item>("_purchaseInfo"))
               .KeyColumns.Add("ITEMNR")
               .KeyColumns.Add("SUPPLIERNR").PropertyRef("SupplierCode");
       }
   }

Test (this is how I'm trying to do it currently)

    [Test]
    public void CanMapItem()
    {
        new PersistenceSpecification<Item>(Session)
            .CheckProperty(a => a.Id, 1234)
            .CheckProperty(a => a.SupplierCode, "S01")
            .CheckList<Item, PurchaseInfo>(Reveal.Member<Item>("_purchaseInfo"), new List<PurchaseInfo>
                                                                    {
                                                                        new PurchaseInfo()
                                                                            {
                                                                                ItemNr = 1234,
                                                                                SupplierCode = "S01"
                                                                            },
                                                                        new PurchaseInfo()
                                                                            {
                                                                                ItemNr = 1234,
                                                                                SupplierCode = "S02"
                                                                            }
                                                                    })
            .VerifyTheMappings();
    }

The compiler complains that CheckList expects as first argument

System.Linq.Expressions.Expression<System.Func<Item, System.Collections.Generic.IEnumerable<PurchaseInfo>>

while Reveal.Member returns

System.Linq.Expressions.Expression<System.Func<Item, object>>

Answer 1

Reveal.Member has 2 overloads, one common and one special. use the special one:

.CheckList<Item, PurchaseInfo>(Reveal.Member<Item, IEnumerable<PurchaseInfo>>("_purchaseInfo"),