Fix PostgreSQL error when deleting an empty collection in a protected…

… resource (fixes #528)

CHANGELOG.rst

@@ -24,6 +24,11 @@ This document describes changes between each past release.
 - Follow redirections in batch subrequests (fixes #511)
 - Add a ``readonly`` setting to run the service in read-only mode. (#525)
 
+**Bug fixes**
+
+- Fix PostgreSQL error when deleting an empty collection in a protected
+  resource (fixes #528)
+
 **Internal changes**
 
 - Switch to SQLAlchemy for smarter connections pools.

cliquet/permission/postgresql/__init__.py

@@ -308,6 +308,9 @@ def replace_object_permissions(self, object_id, permissions):
             conn.execute(insert_query, placeholders)
 
     def delete_object_permissions(self, *object_id_list):
+        if len(object_id_list) == 0:
+            return
+
         query = """
         DELETE FROM access_control_entries
          WHERE object_id IN %(object_id_list)s;"""

cliquet/tests/test_permission.py

@@ -405,6 +405,9 @@ def test_delete_object_permissions_remove_all_given_objects_acls(self):
         self.assertDictEqual(self.permission.object_permissions(
             '/url/a/id/3'), {"create": {"user4"}})
 
+    def test_delete_object_permissions_supports_empty_list(self):
+        self.permission.delete_object_permissions()  # Not failing
+
 
 class MemoryPermissionTest(BaseTestPermission, unittest.TestCase):
     backend = memory_backend