[Buildbot-devel] More Property confusion

[Alexander Sack]

Hi Folks:

So I want to write a custom BuildStep that as an argument to its ctor
has a filename.  This filename can be either a simple string or
hopefully a WithProperties instance to be interpolated by the time
start() runs.

e.g.

class FooFile(BuildStep):
    def __init__(self, filename = filename, **kwargs):
        BuildStep.__init__(self, **kwargs)
        self.filename = filename
        self.addFactoryArguments(filename = filename)

    def start(self):
        """ Do something with self.filename """

But self.filename is a WithProperties() instance.  When start() funs,
self.filename is still a WithProperties instance, not the string (so
my open() fails).

How do use WithProperties() within a custom buildstep?  I was groking
for a concrete example but so far haven't found any.

Do I really have to check the type, a la:

if isinstance(value, WithProperties):
      self.build.getProperties().render(value)

Cheers,

-aps