@cqi @jkaluza @ralph could you please review?

:+1:

It might be a good idea to disallow certain keys in optional_dict. For example, if optional parameter contains any of these it would cause a confusing behavior: scmurl, branch, buildrequire_overrides, require_overrides.

Good idea. I should probably make this a separate PR though since this problem existed before this PR.

@lucarval, I submitted a PR that should address this:
https://pagure.io/rpkg/pull-request/391

:+1:

@lsedlar could you please review this as well?

:thumbsup:

A minor suggestion is to validate --buildrequires and --requires values during argparse parses option values. Setting a validation function to argument type parameter.

FYI adding kwargs not at the end is not backwards compatible and would break users that call the method without naming the kwargs. But hey, that does not happen here, so +1 for this more reasonable ordering.

Looks good to me. :thumbsup: