c# - moq callback makes linq throw exception -

i using moq , ef6.

i need query table , if there less 5 dates in table need add more.

so, in code:

    public void fillpartylist(observablecollection<party> argpartylist)     {         argpartylist.clear();          using (ipartytrackerdataaccess localdb = locator.resolve<ipartytrackerdataaccess>())         {             initializedates(localdb);              var locallist = (from templist in localdb.parties                              templist.partydate >= datetime.now.date                              select templist);              foreach (party currentparty in locallist)             {                 argpartylist.add(currentparty);             }         }      } 

inside "initializedates" query database see how many dates there , add enough make 5. there rules around creating dates [e.g. on fri or sat, etc] not trivial. then, when method comes full list database , add parameter.

my problem comes when try test this. here's test.

    public void testinitializedates()     {         //expected data         int callcount = 0;         int addparty = 0;         int savechanges = 0;         observablecollection<party> partylist = new observablecollection<party>();          //mock data         iqueryable<party> partydata = new list<party>().asqueryable();         iqueryable<systemsetting> settingsdata = new list<systemsetting>().asqueryable();          //setup mock         mock<partytrackerentities> mockcontext = setupdbcontext();          setupapplicationsettings(mockcontext, settingsdata);         setuppartydbset(mockcontext, partydata);          locator.register<iapplicationsettings, applicationsettings>();          //if keep following line exception when querying "database" parties.         mockcontext.setup(m => m.parties.add(it.isany<party>())).callback(() => addparty = callcount++);         mockcontext.setup(m => m.savechanges()).callback(() => savechanges = callcount++);          //run tests          partytrackermodel localmodel = new partytrackermodel();          localmodel.fillpartylist(partylist);          assert.areequal(1, callcount);         assert.areequal(0, savechanges);     }      private mock<dbset<party>> setuppartydbset(mock<partytrackerentities> argdbcontext, iqueryable<party> argpartydata)     {          //mock objects         mock<dbset<party>> mockpartyset = new mock<dbset<party>>();          mockpartyset.as<iqueryable<party>>().setup(m => m.provider).returns(argpartydata.provider);         mockpartyset.as<iqueryable<party>>().setup(m => m.expression).returns(argpartydata.expression);         mockpartyset.as<iqueryable<party>>().setup(m => m.elementtype).returns(argpartydata.elementtype);         mockpartyset.as<iqueryable<party>>().setup(m => m.getenumerator()).returns(argpartydata.getenumerator());          argdbcontext.setup(m => m.parties).returns(mockpartyset.object);          return mockpartyset;     } 

edit: got distracted , didn't finish question.

everything works fine until add setup increments counter, linq in initializedates() fails.

how increment counter , leave dbset<> mocking properly? how query "database" , still count calls add? if setup context.parties.add() count calls linq query blows up.

what doing wrong?

edit: adding initializedates(). note: none of has problem until add moq.callback.

    private static void initializedates(ipartytrackerdataaccess arglocaldb)     {         iapplicationsettings localappsettings = locator.resolve<iapplicationsettings>();          //using (partytrackerentities localdb = new partytrackerentities())         {             //todo: move code partytrackerdb class.             //technically communicate database ,              //make sure there @ least 5 parties in future.             var sqlpartylist = linqlist in arglocaldb.parties                                linqlist.partydate >= datetime.now.date                                select linqlist;             list<party> partylist;             try             {                 partylist = sqlpartylist.orderbydescending(argorder => argorder.partydate).take(5).tolist();             }             catch (sqlexception)             {                 //messagebox.show("cannot connect database. please ensure sqlserver running , accessable machine.");                 throw;             }              if (partylist.count < 5)             {                 datetime maxpartydate = partylist.count <= 0                                             ? datetime.now.date.adddays(-1)                                             : partylist.max(argmaxdate => argmaxdate.partydate);                  //<= 4 because  partylist.count zero-based 5 parties.                 (int shortdaycount = partylist.count; shortdaycount <= 4; shortdaycount++)                 {                     int dateoffset;                     decimal coupledonation;                     decimal singlemaledonation;                     decimal singlefemaledonation;                     decimal sponsoredmaledonation;                     if (maxpartydate.dayofweek == dayofweek.friday) //if last party in list on friday, need add saturday                     {                         //get donation amounts                         //get saturday donations                         coupledonation = localappsettings.satcoupledonation;                         singlemaledonation = localappsettings.satsinglemaledonation;                         singlefemaledonation = localappsettings.satsinglefemaledonation;                         sponsoredmaledonation = localappsettings.satsponsoredmaledonation;                          //add sat                         dateoffset = 1;                     }                     else //otherwise need add friday                     {                         //get donation amounts                         //get friday donations                         coupledonation = localappsettings.fricoupledonation;                         singlemaledonation = localappsettings.frisinglemaledonation;                         singlefemaledonation = localappsettings.frisinglefemaledonation;                         sponsoredmaledonation = localappsettings.frisponsoredmaledonation;                          if (maxpartydate.dayofweek == dayofweek.saturday)                         {                             dateoffset = 6;                         }                         else                         {                             dateoffset = 5 - (int)maxpartydate.dayofweek;                         }                     }                     party newparty = new party                     {                         partydate = maxpartydate.adddays(dateoffset),                         coupledonation = coupledonation,                         singlemaledonation = singlemaledonation,                         singlefemaledonation = singlefemaledonation,                         sponsoredmaledonation = sponsoredmaledonation                     };                      arglocaldb.parties.add(newparty);                      maxpartydate = newparty.partydate;                 }                  arglocaldb.savechanges();              }         }     }