Hello guys,

i am unable to cover a opportunityLineItem formula field "product_family__c " (Formula=TEXT(PricebookEntry.Product2.Family))
in my test class. I queried the field in my controller like this : 

public List <oppProduct> getOli (){
        if(productList ==null){
            productList = new List <oppProduct>();
            for(OpportunityLineitem oli : 
                [select Id, Quantity, Produkt__c, UnitPrice , ON_product_family__c, Product2.Name, ON_Produktbeschreibung_detailliert__c From OpportunityLineitem 
                        WHERE Opportunity.Id = :opportunityId
                        AND ON_product_family__c = 'Extra Boost']){
                productList.add(new oppProduct(oli));   
        
            }   
        }
        return productList; 
    }

In my test class i created the necessary test data, but the value is always Null in the bold system.assertEquals statement

@isTest static void testGetOli () {
        
        List<CreateMultiExtraBoost.oppProduct> productListTest = new List <CreateMultiExtraBoost.oppProduct>();         
        Id pricebookId = Test.getStandardPricebookId();

        Product2 pro = new Product2();
        pro.name = 'test';
        pro.Produktbeschreibung_detailliert__c = 'test';
        pro.Family = 'Extra Boost'; 
        pro.IsActive = true;
        insert pro;
// 
        system.assertEquals('Extra Boost', pro.Family ); 

        
        Product2 pro1 = new Product2();
        pro1.name = 'test';
        pro1.Produktbeschreibung_detailliert__c = 'test';
        pro1.Family = 'Sonstiges'; 
        pro1.IsActive = true;
        insert pro1;
        system.assertEquals('Sonstiges', pro1.Family );

        
        PricebookEntry pEntry = new PricebookEntry (); 
        pEntry.Product2Id = pro.id;
        pEntry.UseStandardPrice = false;
        pEntry.UnitPrice = 600; 
        pEntry.Pricebook2Id = pricebookId;
        pEntry.IsActive = true;
        insert pEntry; 
        system.assertEquals(pro.id, pEntry.Product2Id);

              
        List<Product2> p = [Select Family FROM Product2 WHERE isActive=true];
        List<PricebookEntry> pe = [Select Product2.Family FROM PricebookEntry];

        system.assertEquals('01sD0000000hbEh', pEntry.Pricebook2Id );
        system.assertEquals('Extra Boost', pEntry.Product2.Family);

          
        PricebookEntry pEntry1 = new PricebookEntry (); 
        pEntry1.Product2Id = pro1.id;
        pEntry1.UseStandardPrice = false;
        pEntry1.UnitPrice = 300; 
        pEntry1.Pricebook2Id = pricebookId;
        pEntry1.IsActive = true;
        insert pEntry1;   

        
        Opportunity opp = new Opportunity ();
        opp.name = 'test';
        opp.StageName = '40 - Demo Termin vereinbart';
        opp.Override_Region__c = 'München';
        opp.CloseDate = System.today();
        insert opp;
        
        OpportunityLineItem oli = new OpportunityLineItem ();
        oli.TotalPrice = 500;
        oli.Quantity = 4;
        oli.OpportunityId = opp.Id;
        oli.Product2Id = pro.id;
        oli.ON_Produktbeschreibung_detailliert__c = 'test';                            
        oli.PricebookEntryId = pEntry.id;
        insert oli;
           
        system.assertEquals(4,oli.Quantity );
        system.assertEquals(pro.id,oli.Product2Id );
        system.assertEquals(pEntry.id,oli.PricebookEntryId );
        system.assertEquals(opp.Id,oli.OpportunityId );
        system.assertEquals('Extra Boost', oli.ON_product_family__c);
        
        OpportunityLineItem oli1 = new OpportunityLineItem ();
        oli1.TotalPrice = 500;
        oli1.Quantity = 4;
        oli1.OpportunityId = opp.Id;
        oli1.ON_Produktbeschreibung_detailliert__c = 'test';
        oli1.Product2Id = pro1.id;
        oli1.PricebookEntryId = pEntry1.id;
        insert oli1; 
        
        update opp;
        
        
                     
        CreateMultiExtraBoost cme = new CreateMultiExtraBoost();
        
        if (productListTest == Null){
            for(OpportunityLineitem olip : 
                    [select Id, Quantity, Produkt__c, UnitPrice , ON_product_family__c, Product2.Name, ON_Produktbeschreibung_detailliert__c From OpportunityLineitem 
                            WHERE Opportunity.Id = :opp.Id
                            AND ON_product_family__c = 'Extra Boost']){
                            productListTest.add(new CreateMultiExtraBoost.oppProduct(olip)); 
                            }    
               
        }                       
        
                cme.getOli();
                                  
    }

I inserted the records and queried them, but unfortunately it doesen't work. 
Thanks for your time and your help! 

cheers, 

Sandra