anchor.diff:  void f() {}
   
   void g() {
  -  f(a: ^);
  +  f(j: ^);
   }
   ''', null);
     }
  
positive.code:   Future<void> test_argumentList_requiredPositional_last() async {
      await assertContextType('''
  void f(int i, String str, bool b) {}
  void g(int j) {
    f(1, '2', t^);
  }
  ''', 'bool');
    }
  
negative.code:   Future<void> test_argumentList_requiredPositional_middle2() async {
      await assertContextType('''
  void f(int i, String str, bool b) {}
  void g() {
    f(1, ^, );
  }
  ''', 'String');
  