Error on process return of sale
In Tryton 4.0, when we try process sale on return, it get:
ERROR:tryton.common.common:Traceback (most recent call last):
File "/site-packages/trytond/wsgi.py", line 47, in dispatch_request
return endpoint(request, **request.view_args)
File "/site-packages/trytond/protocols/dispatcher.py", line 59, in rpc
request, database_name, *request.params)
File "/site-packages/trytond/wsgi.py", line 39, in auth_required
return wrapped(*args, **kwargs)
File "/site-packages/trytond/protocols/dispatcher.py", line 40, in wrapper
return func(request, pool, *args, **kwargs)
File "/site-packages/trytond/protocols/dispatcher.py", line 201, in _dispatch
result = rpc.result(meth(*c_args, **c_kwargs))
File "/trytond/modules/sale_pos/sale.py", line 88, in process
super(Sale, cls).process(sales)
File "/site-packages/trytond/model/modelview.py", line 625, in wrapper
return func(cls, *args, **kwargs)
File "/site-packages/trytond/modules/sale/sale.py", line 917, in process
sale.create_shipment('return')
File "/trytond/modules/sale_pos/sale.py", line 194, in create_shipment
return super(Sale, self).create_shipment(shipment_type)
File "/site-packages/trytond/modules/sale_supply/sale.py", line 28, in create_shipment
shipments = super(Sale, self).create_shipment(shipment_type)
File "/site-packages/trytond/modules/sale/sale.py", line 829, in create_shipment
moves = sorted(moves, key=keyfunc)
File "/site-packages/trytond/modules/sale/sale.py", line 788, in _group_shipment_key
planned_date = max(m.planned_date for m in moves)
TypeError: unorderable types: NoneType() > NoneType()
unorderable types: NoneType() > NoneType()