old_contents: # -*- encoding: utf-8 -*-
  ##############################################################################
  #
  #    This program is free software: you can redistribute it and/or modify
  #    it under the terms of the GNU Affero General Public License as published
  #    by the Free Software Foundation, either version 3 of the License, or
  #    (at your option) any later version.
  #
  #    This program is distributed in the hope that it will be useful,
  #    but WITHOUT ANY WARRANTY; without even the implied warranty of
  #    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  #    GNU General Public License for more details.
  #
  #    You should have received a copy of the GNU Affero General Public License
  #    along with this program.  If not, see http://www.gnu.org/licenses/.
  #
  ##############################################################################
  
  from openerp import models, fields, api
  
  
  class ProductSupplierinfo(models.Model):
      _inherit = 'product.supplierinfo'
  
      type = fields.Selection([('customer', 'Customer'),
                               ('supplier', 'Supplier')], string='Type',
                              default='supplier')
      name = fields.Many2one(domain=[])
  
      @api.multi
      @api.onchange('type')
      def onchange_type(self):
          if self.type == 'supplier':
              return {'domain': {'name': [('supplier', '=', True)]}}
          elif self.type == 'customer':
              return {'domain': {'name': [('customer', '=', True)]}}
          return {'domain': {'name': []}}
  
new_contents: # -*- encoding: utf-8 -*-
  ##############################################################################
  #
  #    This program is free software: you can redistribute it and/or modify
  #    it under the terms of the GNU Affero General Public License as published
  #    by the Free Software Foundation, either version 3 of the License, or
  #    (at your option) any later version.
  #
  #    This program is distributed in the hope that it will be useful,
  #    but WITHOUT ANY WARRANTY; without even the implied warranty of
  #    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  #    GNU General Public License for more details.
  #
  #    You should have received a copy of the GNU Affero General Public License
  #    along with this program.  If not, see http://www.gnu.org/licenses/.
  #
  ##############################################################################
  
  from openerp import models, fields, api
  
  
  class ProductSupplierinfo(models.Model):
      _inherit = 'product.supplierinfo'
  
      type = fields.Selection([('customer', 'Customer'),
                               ('supplier', 'Supplier')], string='Type',
                              default='supplier')
  
      @api.multi
      @api.onchange('type')
      def onchange_type(self):
          if self.type == 'supplier':
              return {'domain': {'name': [('supplier', '=', True)]}}
          elif self.type == 'customer':
              return {'domain': {'name': [('customer', '=', True)]}}
          return {'domain': {'name': []}}
  
subject: Update product_supplierinfo.py