source:
  schema:
    $wildchild:
      constraint: false
      ~$wilderchild: {}

  access:
    - location: /
      read: true
      write: true

expected: {"rules":{".write":"false",".read":"true","$wildchild":{".write":"false",".read":"true","$wilderchild":{".write":"false",".validate":"false",".read":"true"}}}}