babel/packages/babel-parser/test/fixtures/experimental/pipeline-operator/invalid-proposal/options.json

{
  "plugins": [
    [
      "pipelineOperator",
      {
        "proposal": "invalid"
      }
    ],
    "estree"
  ],
  "throws": "\"pipelineOperator\" requires \"proposal\" option whose value must be one of: \"minimal\", \"fsharp\", \"hack\", \"smart\"."
}