New linter: Don't `write` on a computed field

[pedrobaeza]

Or bad things will happen

Example:

https://github.com/OCA/stock-logistics-warehouse/blob/9f0124ade73a167c7f512f7f4aef57e6a4ffceb0/sale_stock_available_info_popup/models/sale_order.py#L39

Immediate solution: do update instead.

[moylop260]

Hi Pedro

Thank you for creating this issue

I have been this lint in my mind a long time ago

[FedericoGregori]

Sorry I don't understand the "Or bad things will happen". Can I ask an example? This is a huge thing to teach to every dev I think.

[pedrobaeza]

Onchange methods are executed in "edit-mode", so you need to save to get the definitive values saved on the DB, but if you do a write on it, that changes are immediately saved to the DB, so if you discard the changes on UI, you will have inconsistent data. That's why you have to do update instead, that only modifies the temporary dataset.

The same applies with create and with unlink.

[voronind]

It is hard to distinguish write on record or non-record object.

[moylop260]

It is hard to distinguish write on record or non-record object.

Yes, it is hard.

Instead, We could check all the fields with compute parameter and check if that method has a write

I mean,

name = fields.Char(compute="_compute_name")

Then get the method "_compute_name" and check if is using ".write("

[voronind]

I mean

def _compute_name(self):
    ...
    with open('file.txt', 'wb') as file:
        file.write(b'some')

[moylop260]

In this case the write is a method of a built-in object file

Ast detects this so we could discard all detected ones

[moylop260]

@antonag32 Could you check it, please?

[antonag32]

@moylop260 Yes, will start working on it

[voronind]

In this case the write is a method of a built-in object file

Ast detects this so we could discard all detected ones

OK. And in this case?

def _compute_name(self):
    ...
    unknown_type_object = self._get_object()
    unknown_type_object.write(b'some')

[moylop260]

It should came from a browse variable or only self

[moylop260]

I was testing the checker and the following line was detected in Odoo core

Do you know if there is a valid case to use write or could be it a valid error?

• https://github.com/odoo/odoo/blob/d8d47f9ff8554f4b39487fd2f13c153c7d6f958d/addons/product_margin/models/product_product.py#L179

[moylop260]

New findings updated from odoo repos

odoo/odoo@16.0

addons/fleet/models/fleet_vehicle.py:141:12: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)
addons/product_margin/models/product_product.py:179:12: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)
addons/resource/models/resource.py:228:12: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)
addons/resource/models/resource.py:239:12: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)

odoo/enterprise@16.0

account_batch_payment/models/account_payment.py:22:12: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)
helpdesk/models/helpdesk_ticket.py:368:12: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)
hr_payroll/models/hr_payslip_run.py:48:16: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)
hr_payroll/models/hr_payslip.py:755:8: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)
hr_payroll/models/hr_payslip.py:766:12: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)
l10n_be_hr_payroll/models/l10n_be_274_XX.py:174:12: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)
l10n_be_hr_payroll/models/l10n_be_281_10.py:166:12: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)
l10n_be_hr_payroll/models/l10n_be_281_45.py:89:12: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)
l10n_be_hr_payroll/models/l10n_be_individual_account.py:54:12: E8135: Compute method calling `write`. Use `update` instead. (no-write-in-compute)

[pedrobaeza]

I would say all of them are errors.

[moylop260]

FYI @xmo-odoo

[tde-banana-odoo]

Lot of them are related to HR apps, I warned mighty @tivisse.

[tivisse]

Incoming fixes: https://github.com/odoo/odoo/pull/104419 https://github.com/odoo/enterprise/pull/33366

Thanks for the report ! :100:

Have a nice day,

Yannick.