Swift: Add upgrade and downgrade scripts

Author: jketema

swift/downgrades/33e5e5e03bd3f98322f4c67aefa81015be832b88/downgrades.ql

@@ -0,0 +1,59 @@
+class Element extends @element {
+  string toString() { none() }
+}
+
+class Expr extends @expr {
+  string toString() { none() }
+}
+
+class Decl extends @decl {
+  string toString() { none() }
+}
+
+class DeclOrNone extends @decl_or_none {
+  string toString() { none() }
+}
+
+class ModuleOrNone extends @module_decl_or_none {
+  string toString() { none() }
+}
+
+class Type extends @type {
+  string toString() { none() }
+}
+
+class TypeOrNone extends @type_or_none {
+  string toString() { none() }
+}
+
+query predicate new_decls(Decl decl, ModuleOrNone moduleOrNone) {
+  decls(decl, moduleOrNone) and not using_decls(decl)
+}
+
+query predicate new_decl_members(Decl decl, int index, DeclOrNone declOrNone) {
+  decl_members(decl, index, declOrNone) and not using_decls(decl)
+}
+
+query predicate new_expr_types(Expr id, TypeOrNone typeOrNone) {
+  expr_types(id, typeOrNone) and not unsafe_exprs(id)
+}
+
+query predicate new_types(Type id, string name, TypeOrNone typeOrNone) {
+  types(id, name, typeOrNone) and not inline_array_types(id, _, _)
+}
+
+query predicate new_unspecified_elements(Element id, string property, string error) {
+  unspecified_elements(id, property, error)
+  or
+  using_decls(id) and
+  property = "" and
+  error = "UsingDecl removed during database downgrade. Please update your CodeQL."
+  or
+  unsafe_exprs(id) and
+  property = "" and
+  error = "UnsafeExpr removed during database downgrade. Please update your CodeQL."
+  or
+  inline_array_types(id, _, _) and
+  property = "" and
+  error = "InlineArrayType removed during database downgrade. Please update your CodeQL."
+}