QL: correctly resolve super calls in char preds

Author: erik-krogh

ql/src/codeql_ql/ast/internal/Predicate.qll

@@ -81,7 +81,7 @@ private module Cached {
     // super calls
     exists(Super sup, ClassType type, Type supertype |
       mc.getBase() = sup and
-      sup.getEnclosingPredicate().(ClassPredicate).getParent().getType() = type and
+      sup.getEnclosingPredicate().getParent().(Class).getType() = type and
       supertype in [type.getASuperType(), type.getAnInstanceofType()] and
       p = supertype.getClassPredicate(mc.getMemberName(), mc.getNumberOfArguments())
     )

ql/test/callgraph/Baz.qll

@@ -0,0 +1,11 @@
+class Foo extends string {
+  Foo() { this = "Foo" }
+
+  string getImportedPath() { none() }
+}
+
+class Bar extends string, Foo {
+  Bar() { exists(Foo.super.getImportedPath()) }
+
+  override string getImportedPath() { none() }
+}

ql/test/callgraph/callgraph.expected

@@ -1,5 +1,6 @@
 getTarget
 | Bar.qll:5:38:5:47 | PredicateCall | Bar.qll:8:3:8:31 | ClasslessPredicate snapshot |
+| Baz.qll:8:18:8:44 | MemberCall | Baz.qll:4:3:4:37 | ClassPredicate getImportedPath |
 | Foo.qll:5:26:5:30 | PredicateCall | Foo.qll:3:1:3:26 | ClasslessPredicate foo |
 | Foo.qll:10:21:10:25 | PredicateCall | Foo.qll:8:3:8:28 | ClassPredicate bar |
 | Foo.qll:14:30:14:40 | MemberCall | Foo.qll:10:3:10:27 | ClassPredicate baz |