{
  "expression": ["join", ["literal", []], ","],
  "inputs": [[{}, {}]],
  "expected": {
    "compiled": {
      "result": "success",
      "isFeatureConstant": true,
      "isZoomConstant": true,
      "type": "string"
    },
    "outputs": [""],
    "serialized": ""
  }
}