{
  "version": 8,
  "name": "Test",
  "sources": {
    "usedsource": {
      "tiles": [],
      "type": "vector"
    },
    "unusedsource": {
      "tiles": [],
      "type": "vector"
    }
  },
  "layers": [{
    "id": "usedlayer",
    "type": "symbol",
    "source": "usedsource"
  }, {
    "id":  "unusedlayeropacity",
    "type": "symbol",
    "source": "unusedsource",
    "paint" : {
        "icon-opacity" : 0,
        "text-opacity" : 0
    }
  }, {
    "id":  "unusedlayervisibility",
    "type": "symbol",
    "source": "unusedsource",
    "layout" : {
        "visibility" : "none"
    }
  }, {
    "id":  "classylayer",
    "type": "symbol",
    "source": "unusedsource",
    "paint" : {
        "icon-opacity" : 0,
        "text-opacity" : 0
    },
    "paint.visible" : {
        "icon-opacity" : 1,
        "text-opacity" : 1
    }
  }]
}