Get tax codes for charge line/purchase order line/invoice line

    PurchTotals             purchTotals;
    TaxPurch                taxPurch;
    TmpTaxWorkTrans         tmpTaxWorkTrans;
    VendInvoiceInfoTable    vendInvoiceInfoTable;
    MarkupTrans             markupTrans;

    // Invoice
    purchTotals = PurchTotals::newParmTable(
                vendInvoiceInfoTable,
                PurchUpdate::All,
                AccountOrder::None,
                vendInvoiceInfoTable.ParmId,
                '',
                vendInvoiceInfoTable.Ordering);
    purchTotals.calc();
    taxPurch = purchTotals.tax();

    // PO
    taxPurch = PurchTotals::getTax(purchTable);


  
    taxPurch.showTaxesSourceSingleLine(markupTrans.TableId, markupTrans.RecId, true); // markupTrans could be also PurchLine, VendInvoiceInfoLine
    tmpTaxWorkTrans = taxPurch.tmpTaxWorkTrans();

    while select tmpTaxWorkTrans
            where   tmpTaxWorkTrans.SourceRecId     == markupTrans.RecId
                 && tmpTaxWorkTrans.SourceTableId   == markupTrans.TableId
    {
        info(strFmt("code: %1, amount %2", tmpTaxWorkTrans.TaxCode, tmpTaxWorkTrans.TaxAmount));
    }