[Buildbot-devel] using **kwargs with MasterShellCommand

[Tom Prince]

The problem you are encountering is due to the fact that a build step
instance needs to act both as a instance and as a factory.

You need to add an addFactoryArguments call to the constructor as
detailed here:
http://buildbot.net/buildbot/docs/current/manual/customization.html#writing-buildstep-constructors

This state of affairs isn't ideal, and has been fixed in trunk.

  Tom