Impacted versions:
11.0

I don't know if it is an issue, but I think is strange.

`product_qty` is in unit of `product` : https://github.com/odoo/odoo/blob/11.0/addons/stock/models/stock_move.py#L240
`reserved_availability` is in unit of `stock.move` : https://github.com/odoo/odoo/blob/11.0/addons/stock/models/stock_move.py#L295

`move.product_qty - move.reserved_availability` seems to have no sens, no ?

https://github.com/odoo/odoo/blob/11.0/addons/stock/models/stock_move.py#L915
https://github.com/odoo/odoo/blob/11.0/addons/stock/models/stock_move.py#L917
https://github.com/odoo/odoo/blob/11.0/addons/stock/models/stock_move.py#L924

thank for your answer

@jco-odoo 
@alnslang 


'location_dest_id': self.customer_location.id,
            'partner_id': partner.id,
            'picking_type_id': self.env.ref('stock.picking_type_out').id,
        })
        
        self.env['stock.move'].create({
            'name': 'test_immediate_validate_4',
            'location_id': self.stock_location.id,
            'location_dest_id': self.customer_location.id,
            'picking_id': picking.id,
            'product_id': self.product3.id,
            'product_uom': self.uom_unit.id,
            'product_uom_qty': 5.0,
        })
        picking.action_confirm()
        picking.action_assign()
        
        immediate_trans_wiz_dict = picking.button_validate()
        self.assertEqual(immediate_trans_wiz_dict.get('res_model'), 'stock.immediate.transfer')
        immediate_trans_wiz = self.env[immediate_trans_wiz_dict['res_model']].browse(immediate_trans_wiz_dict['res_id'])
        immediate_trans_wiz.process()
        self.assertEqual(picking.move_lines.quantity_done, 5.0)
        
        self.assertEqual(len(picking.move_lines.move_line_ids), 1)
        self.assertEqual(picking.move_lines.move_line_ids.lot_id, lot1)
        self.assertEqual(picking.move_lines.move_line_ids.qty_done, 5.0)
        
        self.assertEqual(self.env['stock.quant']._get_available_quantity(self.product1, self.stock_location), 0.0)
        self.assertEqual(len(self.env['stock.quant']._gather(self.product1, self.stock_location)), 0.0)
    def _create_picking_test_immediate_validate_5(self, picking_type_id, product_id):