Enable deletion of Conditions.

[plomtask] / plomtask / conditions.py

diff --git a/plomtask/conditions.py b/plomtask/conditions.py
index a45260092fdc6c75a94846eb0893b775eb9316dd..337970924ab25305d64abef13afe24148b0209b1 100644 (file)
--- a/plomtask/conditions.py
+++ b/plomtask/conditions.py
@@ -4,6 +4,7 @@ from typing import Any
 from sqlite3 import Row
 from plomtask.db import DatabaseConnection, BaseModel
 from plomtask.misc import VersionedAttribute
+from plomtask.exceptions import HandledException
 
 
 class Condition(BaseModel[int]):
@@ -35,6 +36,16 @@ class Condition(BaseModel[int]):
         self.title.save(db_conn)
         self.description.save(db_conn)
 
+    def remove(self, db_conn: DatabaseConnection) -> None:
+        """Remove from DB, with dependencies."""
+        assert isinstance(self.id_, int)
+        for item in ('process', 'todo'):
+            for attr in ('conditions', 'enables', 'disables'):
+                table_name = f'{item}_{attr}'
+                for _ in db_conn.row_where(table_name, 'condition', self.id_):
+                    raise HandledException('cannot remove Condition in use')
+        super().remove(db_conn)
+
 
 class ConditionsRelations:
     """Methods for handling relations to Conditions, for Todo and Process."""