actions-runner/src/Runner.Worker/IStepExtensions.cs

using Newtonsoft.Json;

namespace GitHub.Runner.Worker
{
  public static class IStepExtensions
  {
    public static string GetRefName(this IStep step, string defaultRefName = null)
    {
      if (step is JobExtensionRunner extensionRunner && extensionRunner.RepositoryRef != null)
      {
        return JsonConvert.SerializeObject(extensionRunner.RepositoryRef);
      }

      if (step is IActionRunner actionRunner && actionRunner.Action?.Reference != null)
      {
        return JsonConvert.SerializeObject(actionRunner.Action.Reference);
      }

      return defaultRefName;
    }
  }
}