[FIX] account_edi_ubl_cii: fix PriceAmount rounding

In [1], we added a rounding of the amounts in the `<PriceAmount>` tags
to avoid floating point rounding errors. However, it seems the
`float_round` function does not guarantee to avoid these errors.

Take the example of `price_subtotal` = 250.80 and `quantity` = 3.
We will compute the PriceAmount as 250.80 / 3 which yields
83.60000000000001. Even when using `float_round(amount, 10)`, it still
results in the same amount with the rounding error.

For that reason we use the built-in `round` method of Python instead.

[1] 58d57bbbaaab32ba0183890a9182e6de09b32ac5

closes odoo/odoo#156555

X-original-commit: 0b21d562fe4d315c01421b3f242e274830c34e79
Signed-off-by: Laurent Smet (las) <las@odoo.com>
Signed-off-by: Dylan Kiss (dyki) <dyki@odoo.com>

addons/account_edi_ubl_cii/models/account_edi_xml_ubl_20.py

@@ -4,7 +4,6 @@ from lxml import etree
 
 from odoo import models, _
 from odoo.tools import html2plaintext, cleanup_xml_node
-from odoo.tools.float_utils import float_round
 
 
 class AccountEdiXmlUBL20(models.AbstractModel):
@@ -338,7 +337,7 @@ class AccountEdiXmlUBL20(models.AbstractModel):
             'currency_dp': self._get_currency_decimal_places(line.currency_id),
 
             # The price of an item, exclusive of VAT, after subtracting item price discount.
-            'price_amount': float_round(gross_price_unit, 10),
+            'price_amount': round(gross_price_unit, 10),
             'product_price_dp': self.env['decimal.precision'].precision_get('Product Price'),
 
             # The number of item units to which the price applies.

addons/l10n_account_edi_ubl_cii_tests/tests/test_xml_ubl_be.py

@@ -527,15 +527,24 @@ class TestUBLBE(TestUBLCommon, TestAccountMoveSendCommon):
             self.partner_1,
             self.partner_2,
             move_type='out_invoice',
-            invoice_line_ids=[{
-                'product_id': self.product_a.id,
-                'quantity': 3,
-                'price_unit': 102.15,
-                'tax_ids': [Command.set([self.tax_12.id])]
-            }],
+            invoice_line_ids=[
+                {
+                    'product_id': self.product_a.id,
+                    'quantity': 3,
+                    'price_unit': 102.15,
+                    'tax_ids': [Command.set([self.tax_12.id])],
+                },
+                {
+                    'product_id': self.product_a.id,
+                    'quantity': 3,
+                    'price_unit': 83.60,
+                    'tax_ids': [Command.set([self.tax_21.id])],
+                },
+            ],
         )
-        price_amount = etree.fromstring(invoice.ubl_cii_xml_id.raw).find('.//{*}InvoiceLine/{*}Price/{*}PriceAmount')
-        self.assertEqual(price_amount.text, '102.15')
+        price_amounts = etree.fromstring(invoice.ubl_cii_xml_id.raw).findall('.//{*}InvoiceLine/{*}Price/{*}PriceAmount')
+        self.assertEqual(price_amounts[0].text, '102.15')
+        self.assertEqual(price_amounts[1].text, '83.6')
 
     def test_export_tax_exempt(self):
         invoice = self._generate_move(