anchor.diff:        FunctionType type = env.getMemberType(name, cls);
         Expect.isNotNull(type,
             "Member $name not found${cls != null ? ' in class $cls' : ''}.");
  -      DartType returnType = type.returnType;
  +      DartType returnType = type.returnType.withoutNullability;
         Expect.equals(
             expectedType,
  -          '${returnType}',
  +          typeToString(returnType),
             "Unexpected return type for $name"
  -              "${cls != null ? ' in class $cls' : ''}.");
  +          "${cls != null ? ' in class $cls' : ''}.");
         return returnType;
       }
   
  
positive.code: import 'package:compiler/src/elements/entities.dart';
  import 'package:compiler/src/elements/types.dart';
  import 'package:expect/expect.dart';
  import '../helpers/type_test_helper.dart';
  
  main() {
  
negative.code:           "Member $name not found${cls != null ? ' in class $cls' : ''}.");
        Expect.equals(
            expectedType,
            typeToString(type),
            "Unexpected type for $name"
            "${cls != null ? ' in class $cls' : ''}.");
        return type;
      }
  
  