pkg/analyzer_cli/test/data/flutter_analysis_options/packagelist

{
  "configVersion": 2,
  "packages": [
    {
      "name": "flutter",
      "rootUri": "somepkgs/flutter/",
      "packageUri": "lib/"
    },
    {
      "name": "meta",
      "rootUri": "somepkgs/meta/",
      "packageUri": "lib/"
    }
  ]
}