anchor.diff:    a[1] = 42;
   }
   ''');
  -    MethodElement readElement = findElement('[]');
  -    MethodElement writeElement = findElement('[]=');
  +    MethodElement readElement = findElement.method('[]');
  +    MethodElement writeElement = findElement.method('[]=');
       assertThat(readElement).isInvokedAt('[0]', true, length: 1);
       assertThat(writeElement).isInvokedAt('[1]', true, length: 1);
     }
  
positive.code:   a.foo();
  }
  ''');
      Element element = findElement('foo');
      assertThat(element).isInvokedAt('foo();', true);
    }
  
  
negative.code:     ggg(); // nq
    }
  }''');
      PropertyAccessorElement element = findElement.getter('ggg');
      assertThat(element)
        ..isReferencedAt('ggg(); // q', true)
        ..isReferencedAt('ggg(); // nq', false);
  