[FEATURE] fromJson factory on generated '...Result` types.

[RoarGronmo]

Normally there are created fromJson factories in the generated code, which is very conventient to use when iterating through columns with map:

This factory (which is generated):

factory OrdLn.fromJson(Map<String, dynamic> json,
      {ValueSerializer? serializer}) {
    serializer ??= driftRuntimeOptions.defaultSerializer;
    return OrdLn(
      readTime: serializer.fromJson<int>(json['readTime']),
      frmNo: serializer.fromJson<int>(json['frmNo']),
      ordNo: serializer.fromJson<int>(json['ordNo']),
      lnNo: serializer.fromJson<int>(json['lnNo']),
      r1: serializer.fromJson<int?>(json['r1']),
      r3: serializer.fromJson<int?>(json['r3']),
      r4: serializer.fromJson<int?>(json['r4']),
      r5: serializer.fromJson<int?>(json['r5']),
      r10: serializer.fromJson<String?>(json['r10']),
      r11: serializer.fromJson<String?>(json['r11']),
      empNo: serializer.fromJson<int?>(json['empNo']),
      prodPrG2: serializer.fromJson<int?>(json['prodPrG2']),
      prodTp3: serializer.fromJson<int?>(json['prodTp3']),
      un: serializer.fromJson<int?>(json['un']),
      cfDelDt: serializer.fromJson<int?>(json['cfDelDt']),
      ordTp: serializer.fromJson<int?>(json['ordTp']),
      finDt: serializer.fromJson<int?>(json['finDt']),
      delDt: serializer.fromJson<int?>(json['delDt']),
      durDt: serializer.fromJson<int?>(json['durDt']),
      invoMth: serializer.fromJson<int?>(json['invoMth']),
      refNo: serializer.fromJson<int?>(json['refNo']),
      editPref: serializer.fromJson<int?>(json['editPref']),
      prodNo: serializer.fromJson<String?>(json['prodNo']),
      descr: serializer.fromJson<String?>(json['descr']),
      finBy: serializer.fromJson<String?>(json['finBy']),
      invoNo: serializer.fromJson<String?>(json['invoNo']),
      noReg: serializer.fromJson<double?>(json['noReg']),
      admTm: serializer.fromJson<double?>(json['admTm']),
      price: serializer.fromJson<double?>(json['price']),
      noInvAb: serializer.fromJson<double?>(json['noInvAb']),
      am: serializer.fromJson<double?>(json['am']),
      noFin: serializer.fromJson<double?>(json['noFin']),
      dc1P: serializer.fromJson<double?>(json['dc1P']),
      free1: serializer.fromJson<double?>(json['free1']),
      free3: serializer.fromJson<double?>(json['free3']),
      ordLnHash: serializer.fromJson<String?>(json['ordLnHash']),
    );
  }
  @override
  Map<String, dynamic> toJson({ValueSerializer? serializer}) {
    serializer ??= driftRuntimeOptions.defaultSerializer;
    return <String, dynamic>{
      'readTime': serializer.toJson<int>(readTime),
      'frmNo': serializer.toJson<int>(frmNo),
      'ordNo': serializer.toJson<int>(ordNo),
      'lnNo': serializer.toJson<int>(lnNo),
      'r1': serializer.toJson<int?>(r1),
      'r3': serializer.toJson<int?>(r3),
      'r4': serializer.toJson<int?>(r4),
      'r5': serializer.toJson<int?>(r5),
      'r10': serializer.toJson<String?>(r10),
      'r11': serializer.toJson<String?>(r11),
      'empNo': serializer.toJson<int?>(empNo),
      'prodPrG2': serializer.toJson<int?>(prodPrG2),
      'prodTp3': serializer.toJson<int?>(prodTp3),
      'un': serializer.toJson<int?>(un),
      'cfDelDt': serializer.toJson<int?>(cfDelDt),
      'ordTp': serializer.toJson<int?>(ordTp),
      'finDt': serializer.toJson<int?>(finDt),
      'delDt': serializer.toJson<int?>(delDt),
      'durDt': serializer.toJson<int?>(durDt),
      'invoMth': serializer.toJson<int?>(invoMth),
      'refNo': serializer.toJson<int?>(refNo),
      'editPref': serializer.toJson<int?>(editPref),
      'prodNo': serializer.toJson<String?>(prodNo),
      'descr': serializer.toJson<String?>(descr),
      'finBy': serializer.toJson<String?>(finBy),
      'invoNo': serializer.toJson<String?>(invoNo),
      'noReg': serializer.toJson<double?>(noReg),
      'admTm': serializer.toJson<double?>(admTm),
      'price': serializer.toJson<double?>(price),
      'noInvAb': serializer.toJson<double?>(noInvAb),
      'am': serializer.toJson<double?>(am),
      'noFin': serializer.toJson<double?>(noFin),
      'dc1P': serializer.toJson<double?>(dc1P),
      'free1': serializer.toJson<double?>(free1),
      'free3': serializer.toJson<double?>(free3),
      'ordLnHash': serializer.toJson<String?>(ordLnHash),
    };
  }

makes it possible to use code like:

var orderLines = snapshot.data as List<OrdLn>?;
var allKeys = orderLines?.first.toJson().keys.toList();

There OrdLn is one of the generated base classes.

But if I add some additional fields in my query, like theese LEFT JOINS:

  'getOrderOrdLns': 'SELECT olt.*, tt_prodPrG2.txt as prodPrG2_txt '
      'FROM ord_lns_table as olt '
      'LEFT JOIN firms_table as ft ON ft.firm_no = olt.frm_no '
      'LEFT JOIN txts_table AS tt_prodPrG2 ON ((tt_prodPrG2.txt_tp = 21) AND (tt_prodPrG2.lang = ft.ctry) AND (tt_prodPrG2.txt_no = olt.prod_pr_g2)) '
      'WHERE ((olt.frm_no = :frmNo) AND (olt.ord_no = :ordNo)) ',

The result will not be OrdLn but GetOrderOrdLnsResult which does not have factory GetOrderOrdLnsResult.fromJson...

sadly this factory is timeconsuming to create manually... and breaks the dynamic with "automagic" creation as it is now.

It would have been VERY convenient if this factory for the ...Result was created too.