[FIX] point_of_sale: Avoid errors if quantity is 0.

bzr revid: uco@tinyerp.com-20101006064225-y31cvvd5hxq63opz

addons/point_of_sale/pos.py

@@ -1043,6 +1043,7 @@ class pos_order_line(osv.osv):
                     tax_amount = 0.0
                     taxes = [t for t in line.product_id.taxes_id]
                     if line.qty == 0.0:
+                        res[line.id][f] = 0.0
                         continue
                     computed_taxes = account_tax_obj.compute_all(cr, uid, taxes, line.price_unit, line.qty)['taxes']
                     for tax in computed_taxes:

addons/point_of_sale/wizard/pos_return.py

@@ -209,7 +209,8 @@ class pos_return(osv.osv_memory):
                             'date': date_cur,
                             'date_planned': date_cur
                         })
-                        line_obj.copy(cr, uid, line.id, {'qty': -qty, 'order_id': new_order})
+                        if qty != 0.0:
+                            line_obj.copy(cr, uid, line.id, {'qty': -qty, 'order_id': new_order})
                 statementl_obj.create(cr, uid, {
                                                 'name': 'Refund %s'%order_id.name,
                                                 'statement_id': order_id.statement_ids[0].statement_id.id,