[FIX+IMP] _change_generic: Allow to transfer generic stuff between mo…

…dels + fix followers through SQL

Adding a new keyword argument allows us to pass a possible new model for
using this function in other contexts like transferring the generic
stuff from one model to another (e.g. from account.invoice to
account.move in the v12 > v13 migration).

When adding this feature, I have discovered as well a bug in current
code using the SQL method, where barely no followers where transferred,
as the query was not having into account the model, so as soon as the
partner is follower of any record of any model with such ID, then it's
not transferred.

openupgradelib/openupgrade_merge_records.py

@@ -568,16 +568,27 @@ def _adjust_merged_values_sql(env, model_name, record_ids, target_record_id,
 
 
 def _change_generic(env, model_name, record_ids, target_record_id,
-                    exclude_columns, method='orm'):
-    """ Update known generic style res_id/res_model references """
+                    exclude_columns, method='orm', new_model_name=None):
+    """Update known generic style res_id/res_model references.
+    :param env: ORM environment
+    :param model_name: Name of the model that have the generic references.
+    :param record_ids: List of ids of the records to be changed.
+    :param target_record_id: ID of the target record to host the source records
+    :param exclude_columns: list of columns to exclude from the update
+    :param method: 'orm' or 'sql'
+    :param new_model_name: If specified, name of the new model to use in the
+      references. This is useful for being used outside the merge records
+      feature, for example when replacing one model per another (i.e.:
+      account.invoice > account.move).
+    """
     for model_to_replace, res_id_column, model_column in [
-            ('calendar.event', 'res_id', 'res_model'),
-            ('ir.attachment', 'res_id', 'res_model'),
-            ('mail.activity', 'res_id', 'res_model'),
-            ('mail.followers', 'res_id', 'res_model'),
-            ('mail.message', 'res_id', 'model'),
-            ('rating.rating', 'res_id', 'res_model'),
-            ]:
+        ('calendar.event', 'res_id', 'res_model'),
+        ('ir.attachment', 'res_id', 'res_model'),
+        ('mail.activity', 'res_id', 'res_model'),
+        ('mail.followers', 'res_id', 'res_model'),
+        ('mail.message', 'res_id', 'model'),
+        ('rating.rating', 'res_id', 'res_model'),
+    ]:
         try:
             model = env[model_to_replace].with_context(active_test=False)
         except KeyError:
@@ -592,8 +603,11 @@ def _change_generic(env, model_name, record_ids, target_record_id,
                 (model_column, '=', model_name),
                 (res_id_column, 'in', record_ids)])
             if records:
+                vals = {res_id_column: target_record_id}
+                if new_model_name:
+                    vals[model_column] = new_model_name
                 if model_to_replace != 'mail.followers':
-                    records.write({res_id_column: target_record_id})
+                    records.write(vals)
                 else:
                     # We need to avoid duplicated results in this model
                     target_duplicated = model.search([
@@ -604,8 +618,7 @@ def _change_generic(env, model_name, record_ids, target_record_id,
                     dup_partners = target_duplicated.mapped('partner_id')
                     duplicated = records.filtered(lambda x: (
                         x.partner_id in dup_partners))
-                    (records - duplicated).write({
-                        res_id_column: target_record_id})
+                    (records - duplicated).write(vals)
                     duplicated.unlink()
                 logger.debug(
                     "Changed %s record(s) of model '%s'",
@@ -621,13 +634,19 @@ def _change_generic(env, model_name, record_ids, target_record_id,
             }
             query_args = {
                 'model_name': model_name,
+                'new_model_name': new_model_name or model_name,
                 'target_record_id': target_record_id,
                 'record_ids': record_ids,
             }
             query = sql.SQL(
-                """UPDATE {table} SET {res_id_column} = %(target_record_id)s
-                WHERE {model_column} = %(model_name)s
-                """
+                "UPDATE {table} SET {res_id_column} = %(target_record_id)s"
+            ).format(**format_args)
+            if new_model_name:
+                query += sql.SQL(
+                    ", {model_column} = %(new_model_name)s"
+                ).format(**format_args)
+            query += sql.SQL(
+                " WHERE {model_column} = %(model_name)s "
             ).format(**format_args)
             if model_to_replace != 'mail.followers':
                 query += sql.SQL(
@@ -642,6 +661,7 @@ def _change_generic(env, model_name, record_ids, target_record_id,
                         AND partner_id NOT IN (
                             SELECT partner_id FROM {table}
                             WHERE {res_id_column} = %(target_record_id)s
+                                AND {model_column} = %(new_model_name)s
                         )"""
                     ).format(**format_args)
                     logged_query(