tests/standalone/package/scenarios/packages_option_only/sub/.dart_tool/package_config.json

{
  "copyright": [
    "Copyright (c) 2020, the Dart project authors. Please see the AUTHORS ",
    "file for details. All rights reserved. Use of this source code is ",
    "governed by a BSD-style license that can be found in the LICENSE file."
  ],
  "configVersion": 2,
  "packages": [
    {
      "name": "foo",
      "rootUri": "../foo",
      "languageVersion": "2.10"
    }
  ]
}