[IMP] sale: prevent copying down payments when duplicating a SO

addons/sale/models/sale.py

@@ -263,6 +263,14 @@ class SaleOrder(models.Model):
         result = super(SaleOrder, self).create(vals)
         return result
 
+    @api.multi
+    def copy_data(self, default=None):
+        if default is None:
+            default = {}
+        if 'order_line' not in default:
+            default['order_line'] = [(0, 0, line.copy_data()[0]) for line in self.order_line.filtered(lambda l: not l.is_downpayment)]
+        return super(SaleOrder, self).copy_data(default)
+
     @api.multi
     def _prepare_invoice(self):
         """
@@ -740,6 +748,9 @@ class SaleOrderLine(models.Model):
     company_id = fields.Many2one(related='order_id.company_id', string='Company', store=True, readonly=True)
     order_partner_id = fields.Many2one(related='order_id.partner_id', store=True, string='Customer')
     analytic_tag_ids = fields.Many2many('account.analytic.tag', string='Analytic Tags')
+    is_downpayment = fields.Boolean(
+        string="Is a down payment", help="Down payments are made when creating invoices from a sale order."
+        " They are not copied when duplicating a sale order.")
 
     state = fields.Selection([
         ('draft', 'Quotation'),

addons/sale/wizard/sale_make_invoice_advance.py

@@ -151,6 +151,7 @@ class SaleAdvancePaymentInv(models.TransientModel):
                     'product_uom': self.product_id.uom_id.id,
                     'product_id': self.product_id.id,
                     'tax_id': [(6, 0, self.product_id.taxes_id.ids)],
+                    'is_downpayment': True,
                 })
                 self._create_invoice(order, so_line, amount)
         if self._context.get('open_invoices', False):