I'm trying to use the CreateRelease class.

During my first test my code failed due to an auth error.

The problem is that the github library returned a secondary error masking the root cause of the problem.

repos_service: 993 - Failed assertion: boolean expression must not be null

Tracing through the code I believe the problem is caused in the github.requestJson method.

This method calls github.request with a 'null' statusCode.

In the request method I see the following code:

 _updateRateLimit(response.headers);
    if (statusCode != null && statusCode != response.statusCode) {
      if (fail != null) {
        fail(response);
      }
      handleStatusCode(response);
    } else {
      return response;
    }

My reading of this method is that if the statusCode is null then error is ignore.
The requestJson method then tries to decode the response as a CreateRelease object which of course its not.

I think the problem here is that the call to handleStatusCode is only called if a statusCode is passed in.

I would think that the handleStatusCode method should be called even if a statusCode is not passed in.

So I think the code should read:

 _updateRateLimit(response.headers);

      // handle expected status codes.
     if (statusCode != null && statusCode == response.statusCode) {
        return response;
    }
    /// should we consider any 2XX code to be an OK?
    if (response.statusCode != 200)
    {
        if (fail != null) {
           fail(response);
        handleStatusCode(response);
    } else {
      return response;
    }