anchor.diff:          Member,
           Procedure,
           Program,
  +        StaticInvocation,
           SuperMethodInvocation,
           SuperPropertyGet,
           SuperPropertySet,
  
positive.code:   problem(TreeNode node, String details, {TreeNode context}) {
      node ??= (context ?? this.context);
      int offset = node?.fileOffset ?? -1;
      LocatedMessage message = templateInternalVerificationError
          .withArguments(details)
          .withLocation(fileUri == null ? null : Uri.parse(fileUri), offset);
      CompilerContext.current.report(message, Severity.error);
      errors.add(message);
    }
  
negative.code: 
  import '../type_inference/type_schema.dart' show TypeSchemaVisitor, UnknownType;
  
  import 'redirecting_factory_body.dart'
      show RedirectingFactoryBody, getRedirectingFactoryBody;
  
  List<LocatedMessage> verifyProgram(Program program, {bool isOutline: false}) {
    FastaVerifyingVisitor verifier = new FastaVerifyingVisitor(isOutline);
  