config property

Implementation

@override
Map<String, Object?> get config {
  // A world is opened by its file's name — `worlds open --world=…` — so two
  // of one name would be one world written twice.
  var seen = <String, String>{};
  for (var package in packages) {
    for (var world in package.worlds) {
      if (seen[world.id] case var other?) {
        throw StateError(
          'Two worlds are called "${world.id}": ${world.path} in '
          '"${package.path}" and one in "$other". A world is opened by its '
          "file's name, so rename one of the files.",
        );
      }
      seen[world.id] = package.path;
    }
  }
  return {
    'packages': [for (var p in packages) p.toJson()],
  };
}