anchor.diff:    void _preVisit(AssignedVariables<Node, Var> assignedVariables) {}
   
     @override
  -  Type _visit(Harness h) {
  +  Type _visit(Harness h, Type context) {
       return h._typeAnalyzer.analyzeThis(this);
     }
   }
  
positive.code:   void _preVisit(AssignedVariables<Node, Var> assignedVariables) {}
  
    @override
    Type _visit(Harness h) {
      return h._typeAnalyzer.analyzeThisPropertyGet(this, propertyName);
    }
  }
  
negative.code:   void _preVisit(AssignedVariables<Node, Var> assignedVariables) {}
  
    @override
    Type _visit(Harness h, Type context) {
      return h._typeAnalyzer.analyzeBoolLiteral(this, value);
    }
  }
  