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 


'product_uom_qty': 1.0,
        })
        
        self.assertEqual(self.env['stock.quant']._get_available_quantity(self.product1, self.stock_location, lot_id=lot1), 1.0)
        move1._action_confirm()
        move1._action_assign()
        self.assertEqual(move1.state, 'assigned')
        move2._action_confirm()
        move2._action_assign()
        self.assertEqual(move2.state, 'confirmed')
        
        move2._force_assign()
        self.assertEqual(move2.state, 'assigned')
        
        move2.write({'move_line_ids': [(0, 0, {
            'product_id': self.product1.id,
            'product_uom_id': self.uom_unit.id,
            'qty_done': 1,
            'product_uom_qty': 0,
            'lot_id': lot1.id,
            'package_id': False,
            'result_package_id': False,
            'location_id': move2.location_id.id,
            'location_dest_id': move2.location_dest_id.id,
        })]})
        move2._action_done()
        
        self.assertEqual(move1.state, 'confirmed')
        self.assertEqual(self.env['stock.quant']._get_available_quantity(self.product1, self.stock_location, lot_id=lot1), 0.0)
    def test_use_unreserved_move_line_3(self):