[IMP] util/records: skip replace if all ids are the same

If all ids are the same and we are replacing in the same model we
currently cause an error. This is not necessary and could lead to false
errors if the list of mapping ids is correctly the same.

For example sometimes we transform a model A into model B by updating
metadata. Then we insert into B's table, and finally perform a replace
of references from A's table to B's table. This would fail if the ids
are the same. This case will happen with a high probability if there is
only one A record with id=1 since the single B record would get id=1 as
well.

Example logs after the patch:
```
2025-04-14 07:28:32,883 42811 WARNING test_16 odoo.upgrade.util.records: Replace references in model `res.country`, ignoring same-id mapping `{1: 1, 2: 2}`
2025-04-14 07:28:32,883 42811 WARNING test_16 odoo.upgrade.util.records: Nothing to replace in model `res.country`, ignoring empty mapping
```

Author: aj-fuentes

src/base/tests/test_util.py

@@ -1449,6 +1449,11 @@ def test_replace_record_references_batch__uniqueness(self):
         [count] = self.env.cr.fetchone()
         self.assertEqual(count, 1)
 
+    @mute_logger("odoo.upgrade.util.records")
+    def test_replace_record_references_batch__idem_mapping(self):
+        # This logs a warning but shouldn't fail
+        util.replace_record_references_batch(self.env.cr, {1: 1, 2: 2}, "res.country")
+
     def _prepare_test_delete_unused(self):
         def create_cat():
             name = f"test_{uuid.uuid4().hex}"

src/util/records.py

@@ -1469,6 +1469,9 @@ def replace_record_references_batch(cr, id_mapping, model_src, model_dst=None, r
         if same_ids:
             _logger.warning("Replace references in model `%s`, ignoring same-id mapping `%s`", model_src, same_ids)
             id_mapping = {k: v for k, v in id_mapping.items() if k != v}
+            if not id_mapping:
+                _logger.warning("Nothing to replace in model `%s`, ignoring empty mapping", model_src)
+                return
 
     assert id_mapping
     assert all(isinstance(v, int) and isinstance(k, int) for k, v in id_mapping.items())