[FIX] account: fix reconcile rule percentage calculation

In https://github.com/odoo/odoo/pull/52529/commits/078a3a0f760ff24d02070a343f28d2249a8b5ba7#diff-c217a13a40a3cc27dc516b899793abecfac8cab9a42fed407d4776bcbc9de9a8R812
the way the percentage is calculated is changed.
This implies that a reconciliation rule allowing a 90% matching amount will not allow to reconcile
a 90$ bank statement with a 100$ invoice (as it will calculate the % as 88.89%, not meeting the required 90 %)

After cited commit:
invoice 200, bank statement 180:
(|-180| - |20|) / |-180| * 100 = 88.89%
invoice 200, bank statement 220:
(|-220| - |-20|) / |-220| * 100 = 90.91%
credit note 200, bank statement -180:
(|180| - |-20|) / |180| * 100 = 88.89%
credit note 200, bank statement -220:
(|220| - |20|) / |220| * 100 = 90.91%

Now:
invoice 200, bank statement 180:
100 - |20| / |(-180 - 20)| * 100 = 90%
invoice 200, bank statement 220:
100 - |-20| / |(-220 - -20)| * 100 = 90%
credit note 200, bank statement -180:
100 - |-20| / |(180 - -20)| * 100 = 90%
credit note 200, bank statement -220:
100 - |20| / |(220 - 20)| * 100 = 90%

closes odoo/odoo#70948

Task: 2427089
Signed-off-by: William André (wan) <wan@odoo.com>

2 files changed, 35 insertions, 6 deletions

diff --git a/addons/account/models/account_reconcile_model.py b/addons/account/models/account_reconcile_model.py
index 4b866bcbbb6..5a7a99f1ed8 100644
--- a/addons/account/models/account_reconcile_model.py
+++ b/addons/account/models/account_reconcile_model.py
@@ -884,8 +884,7 @@ class AccountReconcileModel(models.Model):
         # Statement line amount is equal to the total residual.
         if line_currency.is_zero(line_residual_after_reconciliation):
             return True
-
-        reconciled_percentage = (abs(line_residual) - abs(line_residual_after_reconciliation)) / abs(line_residual) * 100
+        reconciled_percentage = 100 - abs(line_residual_after_reconciliation) / abs(line_residual - line_residual_after_reconciliation) * 100
         return reconciled_percentage >= self.match_total_amount_param
 
     def _filter_candidates(self, candidates, aml_ids_to_exclude, reconciled_amls_ids):
diff --git a/addons/account/tests/test_reconciliation_matching_rules.py b/addons/account/tests/test_reconciliation_matching_rules.py
index c00fe13cbbd..ed01c56526b 100644
--- a/addons/account/tests/test_reconciliation_matching_rules.py
+++ b/addons/account/tests/test_reconciliation_matching_rules.py
@@ -350,7 +350,7 @@ class TestReconciliationMatchingRules(AccountTestInvoicingCommon):
     def test_matching_fields_match_total_amount(self):
         # Check match_total_amount: line amount >= total residual amount.
         self.rule_1.match_total_amount_param = 90.0
-        self.bank_line_1.amount += 5
+        self.bank_line_1.amount += 10
         self._check_statement_matching(self.rule_1, {
             self.bank_line_1.id: {'aml_ids': [self.invoice_line_1.id], 'model': self.rule_1, 'status': 'write_off', 'partner': self.bank_line_1.partner_id},
             self.bank_line_2.id: {'aml_ids': [
@@ -361,11 +361,11 @@ class TestReconciliationMatchingRules(AccountTestInvoicingCommon):
             self.cash_line_1.id: {'aml_ids': [self.invoice_line_4.id], 'model': self.rule_1, 'partner': self.cash_line_1.partner_id},
         })
         self.rule_1.match_total_amount_param = 100.0
-        self.bank_line_1.amount -= 5
+        self.bank_line_1.amount -= 10
 
         # Check match_total_amount: line amount <= total residual amount.
         self.rule_1.match_total_amount_param = 90.0
-        self.bank_line_1.amount -= 5
+        self.bank_line_1.amount -= 10
         self._check_statement_matching(self.rule_1, {
             self.bank_line_1.id: {'aml_ids': [self.invoice_line_1.id], 'model': self.rule_1, 'status': 'write_off', 'partner': self.bank_line_1.partner_id},
             self.bank_line_2.id: {'aml_ids': [
@@ -376,7 +376,37 @@ class TestReconciliationMatchingRules(AccountTestInvoicingCommon):
             self.cash_line_1.id: {'aml_ids': [self.invoice_line_4.id], 'model': self.rule_1, 'partner': self.cash_line_1.partner_id},
         })
         self.rule_1.match_total_amount_param = 100.0
-        self.bank_line_1.amount += 5
+        self.bank_line_1.amount += 10
+
+        # Check match_total_amount: line amount >= total residual amount, match_total_amount_param just not matched.
+        self.rule_1.match_total_amount_param = 90.0
+        self.bank_line_1.amount += 10.01
+        self._check_statement_matching(self.rule_1, {
+            self.bank_line_1.id: {'aml_ids': []},
+            self.bank_line_2.id: {'aml_ids': [
+                self.invoice_line_1.id,
+                self.invoice_line_2.id,
+                self.invoice_line_3.id,
+            ], 'model': self.rule_1, 'partner': self.bank_line_2.partner_id},
+            self.cash_line_1.id: {'aml_ids': [self.invoice_line_4.id], 'model': self.rule_1, 'partner': self.cash_line_1.partner_id},
+        })
+        self.rule_1.match_total_amount_param = 100.0
+        self.bank_line_1.amount -= 10.01
+
+        # Check match_total_amount: line amount <= total residual amount, match_total_amount_param just not matched.
+        self.rule_1.match_total_amount_param = 90.0
+        self.bank_line_1.amount -= 10.01
+        self._check_statement_matching(self.rule_1, {
+            self.bank_line_1.id: {'aml_ids': []},
+            self.bank_line_2.id: {'aml_ids': [
+                self.invoice_line_1.id,
+                self.invoice_line_2.id,
+                self.invoice_line_3.id,
+            ], 'model': self.rule_1, 'partner': self.bank_line_2.partner_id},
+            self.cash_line_1.id: {'aml_ids': [self.invoice_line_4.id], 'model': self.rule_1, 'partner': self.cash_line_1.partner_id},
+        })
+        self.rule_1.match_total_amount_param = 100.0
+        self.bank_line_1.amount += 10.01
 
     def test_matching_fields_match_partner_category_ids(self):
         test_category = self.env['res.partner.category'].create({'name': 'Consulting Services'})