[18.0][IMP] account_reconcile_oca: onchange manual_partner_id

Manual partner change on liquidity line updates other lines and ensures the consistent partner across all displayed reconcile lines (like in enterprise).
Updating partner on other lines does not propagate.

Author: Qlasta

account_reconcile_oca/models/account_bank_statement_line.py

@@ -508,6 +508,7 @@ def _onchange_manual_reconcile_vals(self):
                 in_currency_date,
             )
         self.previous_manual_amount_in_currency = self.manual_amount_in_currency
+        edited_is_liquidity = False
         for line in data:
             if line["reference"] == self.manual_reference:
                 if self._check_line_changed(line):
@@ -516,7 +517,8 @@ def _onchange_manual_reconcile_vals(self):
                         line["kind"] if line["kind"] != "suspense" else "other"
                     )
                     line.update(line_vals)
-                    if line["kind"] == "liquidity":
+                    edited_is_liquidity = line.get("kind") == "liquidity"
+                    if edited_is_liquidity:
                         self._update_move_partner()
             if self.manual_line_id and self.manual_line_id.id == line.get(
                 "original_exchange_line_id"
@@ -544,6 +546,30 @@ def _onchange_manual_reconcile_vals(self):
         )
         self.can_reconcile = self.reconcile_data_info.get("can_reconcile", False)
 
+        # Ensure the UI shows consistent partner across all displayed lines:
+        # only when editing liquidity line
+        if not edited_is_liquidity:
+            return
+        partner_value = (
+            [self.manual_partner_id.id, self.manual_partner_id.display_name]
+            if self.manual_partner_id
+            else False
+        )
+        info = dict(self.reconcile_data_info or {})
+        reconcile_lines = list(info.get("data") or [])
+        if not reconcile_lines:
+            self.reconcile_data_info = info
+            return
+        updated_lines = []
+        for line in reconcile_lines:
+            new_line = dict(line)
+            # Update only the "other" displayed line(s)
+            if new_line.get("kind") != "liquidity":
+                new_line["partner_id"] = partner_value
+            updated_lines.append(new_line)
+        info["data"] = updated_lines
+        self.reconcile_data_info = info
+
     def _update_move_partner(self):
         if self.partner_id == self.manual_partner_id:
             return

account_reconcile_oca/tests/test_bank_account_reconcile.py

@@ -1473,3 +1473,63 @@ def test_invoice_foreign_currency_late_change_of_rate(self):
             self.assertEqual(3, len(f.reconcile_data_info["data"]))
             self.assertTrue(f.can_reconcile)
             self.assertEqual(f.reconcile_data_info["data"][-1]["amount"], 3.63)
+
+    def test_manual_partner_on_liquidity_propagates_to_other_line(self):
+        # GIVEN
+        partner = self.env["res.partner"].create({"name": "Widget Partner Propagate"})
+        bank_stmt = self.acc_bank_stmt_model.create(
+            {
+                "journal_id": self.bank_journal_euro.id,
+                "date": time.strftime("%Y-07-15"),
+                "name": "test",
+            }
+        )
+        bank_stmt_line = self.acc_bank_stmt_line_model.create(
+            {
+                "name": "testLine",
+                "journal_id": self.bank_journal_euro.id,
+                "statement_id": bank_stmt.id,
+                "amount": 100,
+                "date": time.strftime("%Y-07-15"),
+            }
+        )
+        with Form(
+            bank_stmt_line,
+            view="account_reconcile_oca_2.bank_statement_line_form_reconcile_view",
+        ) as f:
+            widget_lines = f.reconcile_data_info["data"]
+            liquidity_line = None
+            for line_data in widget_lines:
+                if line_data.get("kind") == "liquidity" and line_data.get("id"):
+                    liquidity_line = line_data
+                    break
+            self.assertTrue(liquidity_line)
+            non_liquidity_line = None
+            for line_data in widget_lines:
+                if line_data.get("kind") != "liquidity":
+                    non_liquidity_line = line_data
+                    break
+            self.assertTrue(non_liquidity_line)
+            partner_display_format = [partner.id, partner.display_name]
+            initial_partner = non_liquidity_line.get("partner_id")
+            self.assertNotEqual(
+                initial_partner,
+                partner_display_format,
+            )
+            # WHEN
+            f.manual_reference = f"account.move.line;{liquidity_line['id']}"
+            f.manual_partner_id = partner
+            # THEN
+            updated_widget_lines = f.reconcile_data_info["data"]
+            updated_non_liquidity_line = None
+            for line_data in updated_widget_lines:
+                if line_data.get("kind") != "liquidity":
+                    updated_non_liquidity_line = line_data
+                    break
+            self.assertTrue(
+                updated_non_liquidity_line,
+            )
+            self.assertEqual(
+                updated_non_liquidity_line.get("partner_id"),
+                partner_display_format,
+            )