pkg/front_end/testcases/dart2js/issue56803.dart.textual_outline_modelled.expect

const String? maybe = bool.fromEnvironment("not there") ? "string" : null;

extension type const Ext._(String _) implements String {
  const Ext()
      : assert(maybe != null, "Must not be null"),
        _ = "OK";
}

void main() {}