qmllint rejects enumeration types

When running qmllint on a file that contains an enumeration type as shown in the documentation, it outputs the following error:

qml/test.qml:5 : Unexpected token `reserved word'
qml/test.qml:6 : Expected token `:'

test.qml

import QtQuick 2.9
import QtQuick.Controls 2.2

ApplicationWindow {
    enum ThisIsAnEnum {
        Foo,
        Bar
    }
}

Steps to reproduce

• Run the python:3.6 Docker container bash, with access to test.qml
• Run

  apt-get update
  

• Run

  apt-get install -y qt5-default qtdeclarative5-dev-tools libsdl2-2.0
  

• Run

  qmllint <path-to-file>/test.qml

   

Documentation on the enumeration type: https://doc.qt.io/qt-5/qtqml-syntax-objectattributes.html#enumeration-attributes