[FIX] base: properly execute Selection field ondelete actions

With this commit, 2 changes are made to the way that the
fields.Selection.ondelete cleanup action works:

1) We manually delete ir.model.fields.selection **before** the deletion
of ir.model.fields purposefully to **avoid** SQL CASCADE deletes, as we
do not know which selections are deleted in cascade and thus we cannot
perform the corresponding ondelete cleanup action (which is implemented
within the ORM).

2) In some actions, namely 'set default' and 'set null', we write a
"safe" value to the records containing the Selection being deleted,
before this commit this would go through the ORM (records.write()) but
this is problematic if there's a write override for the record's model
that raises an error for the field being written to. With this commit,
we first try to go through the ORM but if there's a failure (because of
the raise in a write override) then we will bypass the ORM and set it
with SQL.

opw-2451126

closes odoo/odoo#67253

Signed-off-by: Adrian Torres (adt) <adt@odoo.com>

1 files changed, 30 insertions, 8 deletions

diff --git a/odoo/addons/base/models/ir_model.py b/odoo/addons/base/models/ir_model.py
index a2dbffe57b1..acb8476e4c7 100644
--- a/odoo/addons/base/models/ir_model.py
+++ b/odoo/addons/base/models/ir_model.py
@@ -1368,6 +1368,29 @@ class IrModelSelection(models.Model):
 
     def _process_ondelete(self):
         """ Process the 'ondelete' of the given selection values. """
+        def safe_write(records, fname, value):
+            if not records:
+                return
+            try:
+                with self.env.cr.savepoint():
+                    records.write({fname: value})
+            except Exception as e:
+                # going through the ORM failed, probably because of an exception
+                # in an override or possibly a constraint.
+                _logger.warning(
+                    "Could not fulfill ondelete action for field %s.%s, "
+                    "attempting ORM bypass...", records._name, fname,
+                )
+                query = sql.SQL("UPDATE {} SET {}=%s WHERE id IN %s").format(
+                    sql.Identifier(records._table),
+                    sql.Identifier(fname),
+                )
+                # if this fails then we're shit out of luck and there's nothing
+                # we can do except fix on a case-by-case basis
+                value = field.convert_to_column(value, records)
+                self.env.cr.execute(query, [value, records._ids])
+                records.invalidate_cache([fname])
+
         for selection in self:
             Model = self.env[selection.field_id.model]
             # The field may exist in database but not in registry. In this case
@@ -1390,10 +1413,10 @@ class IrModelSelection(models.Model):
             elif callable(ondelete):
                 ondelete(selection._get_records())
             elif ondelete == 'set null':
-                selection._get_records().write({field.name: False})
+                safe_write(selection._get_records(), field.name, False)
             elif ondelete == 'set default':
                 value = field.convert_to_write(field.default(Model), Model)
-                selection._get_records().write({field.name: value})
+                safe_write(selection._get_records(), field.name, value)
             elif ondelete == 'cascade':
                 selection._get_records().unlink()
             else:
@@ -2150,13 +2173,12 @@ class IrModelData(models.Model):
         constraints = self.env['ir.model.constraint'].search([('module', 'in', modules.ids)])
         constraints._module_data_uninstall()
 
-        # Remove fields, selections and relations. Note that the selections of
-        # removed fields do not require any "data fix", as their corresponding
-        # column no longer exists. We can therefore completely ignore them. That
-        # is why selections are removed after fields: most selections are
-        # deleted on cascade by their corresponding field.
-        delete(self.env['ir.model.fields'].browse(unique(field_ids)))
+        # If we delete a selection field, and some of its values have ondelete='cascade',
+        # we expect the records with that value to be deleted. If we delete the field first,
+        # the column is dropped and the selection is gone, and thus the records above will not
+        # be deleted.
         delete(self.env['ir.model.fields.selection'].browse(unique(selection_ids)).exists())
+        delete(self.env['ir.model.fields'].browse(unique(field_ids)))
         relations = self.env['ir.model.relation'].search([('module', 'in', modules.ids)])
         relations._module_data_uninstall()