+
+ // The value might be a string due to the wrong plugin being used for role
+ // field data, and subsequently the incorrect config schema object and
+ // value. In the empty case stop early. Otherwise we cast it to an array
+ // later.
+ if (is_string($this->value) && $this->value === '') {
+ return [];
+ }
+
+ foreach ((array) $this->value as $role_id) {