Swift: database downgrade script

Author: AlexDenisov

swift/downgrades/b83ff9c60c2bb4be2f3d1d4810268c557eb38f19/downgrade.ql

@@ -0,0 +1,23 @@
+class Element extends @element {
+  string toString() { none() }
+}
+
+query predicate new_unspecified_elements(Element e, string property, string error) {
+  unspecified_elements(e, property, error)
+  or
+  error =
+    "DiscardStmt and MaterializePackExpr removed during database downgrade. Please update your CodeQL code." and
+  property = "" and
+  (
+    materialize_pack_exprs(e, _) or
+    discard_stmts(e, _)
+  )
+}
+
+query predicate new_unspecified_element_children(Element e, int index, Element child) {
+  unspecified_element_children(e, index, child)
+  or
+  materialize_pack_exprs(e, child) and index = 0
+  or
+  discard_stmts(e, child) and index = 0
+}