[16.0] account_invoice_fiscal_position_update wrong computation if B2C / B2B mapping.

[legalsylvain]

Module

account_invoice_fiscal_position_update

Describe the bug

when fiscal position is mapping VAT Inc -> VAT Exc (or no vat), the computations of the prices are wrong.

As a result, select product then set fiscal position generates a differente invoice as select fiscal position then, select product.

To Reproduce

Affected versions:

• 16.0
• 17.0 (on runboat, with the current migration PR, here [17.0][MIG] account_invoice_fiscal_position_update: Migration to 17.0 #1630)

Steps to reproduce the behavior:

1. Configure a fiscal position with VAT excl -> VAT excl mapping and Vat INCL -> Vat Excl mapping.

(this is the case, by default with INTRA-EU B2B fiscal position installed by odoo l10n_fr localization).

2. Create 2 product, one with vat Incl and the other with vat Excl

3. Create an Invoice, add the two products. (The untaxed amount is 834.33)

4. Set the fiscal position. The Untaxed amount of the invoice changed. (Now 1001.00)

Expected behavior

If we set first the fiscal position and then select product the result is the following, and is the good one. (834.33)

[juancarlosonate-tecnativa]

I can't find those taxes on products in Intra-EU B2B to reproduce the error. Did you configure them? Could you provide more details so i can check? thanks!

[legalsylvain]

Hi @juancarlosonate-tecnativa. First thanks a lot for your answer !

Indeed, I had renamed the VAT to explain the bug, to be more explicit.

• TTC means "INCLUDED in Price", in french
• In l10n_fr, when "TTC" is NOT mentioned, it means "NOT INCLUDED in Price.

On a fresh instance, If I install l10n_fr then go on the fiscal position Intra-EU B2B, here are the original names :

• l10n_fr.tva_acq_normale : TVA 20% (Sales) (Goods)
• l10n_fr.tva_acq_normale_TTC : TVA 20% TTC (Sales) (Goods)

don't hesitate to let me know if anything remains unclear!

[juancarlosonate-tecnativa]

I can confirm the issue, this does happen. The problem seems to be with the price_unit, but i need to investigate further. Have you managed to find out anything else from a technical perspective? Thanks!

[legalsylvain]

Hi. In V12, I had a similar problem with the following mappings : Excl -> Incl and Incl -> Incl. ("X -> Incl")
The problem was general in Odoo, and I solved it with that module :
https://github.com/grap/grap-odoo-incubator/tree/12.0/account_fiscal_position_tax_included

Now, here it is the Incl >> Excl that is failing. it is a more common case. (all B2C shops, that makes sometimes intracom sales are impacted).

Maybe the module account_invoice_fiscal_position_update should call this core function ?

https://github.com/odoo/odoo/blob/16.0/addons/account/models/account_tax.py#L1317

Thanks for your investigation !