[FIX] point_of_sale: fixed tax price

- Create a tax:
  Fixed price: 0.355
  Included in price
- Assign the tax to product P
- Create a POS order with P and a price 0, pay by bank
- Create a POS order with P and a price 10, pay by bank
- Close the POS session.

The following entry is created:
                      D           C
Tax Received       0.01        0.00
Product Sales      0.00        9.65
Product Sales      0.36        0.00
Receivable        10.00        0.00

Several issues:
- the entry is posted and unbalanced: covered in #48484
- rounding of 0.355 was either 0.36 or 0.35: to fix one day... [1]
- the tax received of 0.36 for the POS order of 0 is booked on the debit
  rather than on credit, leading to a difference 0.01.

This happens because the taxes amounts for the POS order of 10 are
positive, while they should be negative for a sale as done in [2].

We set the amounts as negative as done for incoming invoices, and adapt
the tax line creation accordingly.

[1] The use case is weird: a fixed price of 0.355 while we only have 2
digits in the currency?
[2] https://github.com/odoo/odoo/blob/e415cffa2ffb3fe4b5f0e32bd96b3433387a95e3/addons/account/models/account_move.py#L461

opw-2168096

closes odoo/odoo#49104

X-original-commit: 5df8ed72d03de635f3c38ce59c1b3e9c9ce51ed2
Signed-off-by: Nicolas Martinelli (nim) <nim@odoo.com>

0 files changed, 0 insertions, 0 deletions