Scenario should not depend on list order

issue5017
review21451002

tests/scenario_account_stock_anglo_saxon.rst

@@ -191,10 +191,12 @@ Receive 9 products::
     >>> ShipmentIn = Model.get('stock.shipment.in')
     >>> Move = Model.get('stock.move')
     >>> shipment = ShipmentIn(supplier=supplier)
-    >>> move = Move(purchase.moves[0].id)
+    >>> move, = [m for m in purchase.moves if m.product == product]
+    >>> move = Move(move.id)
     >>> shipment.incoming_moves.append(move)
     >>> move.quantity = 4.0
-    >>> move = Move(purchase.moves[1].id)
+    >>> move, = [m for m in purchase.moves if m.product == product_average]
+    >>> move = Move(move.id)
     >>> shipment.incoming_moves.append(move)
     >>> move.quantity = 5.0
     >>> shipment.click('receive')
@@ -223,9 +225,10 @@ Open supplier invoice::
     >>> Invoice = Model.get('account.invoice')
     >>> purchase.reload()
     >>> invoice, = purchase.invoices
-    >>> invoice_line = invoice.lines[0]
+    >>> invoice_line, = [l for l in invoice.lines if l.product == product]
     >>> invoice_line.unit_price = Decimal('6')
-    >>> invoice_line = invoice.lines[1]
+    >>> invoice_line, = [l for l in invoice.lines
+    ...     if l.product == product_average]
     >>> invoice_line.unit_price = Decimal('4')
     >>> invoice.invoice_date = today
     >>> invoice.click('post')