'Generate a L{FilePath} with one package, named C{pkgname}, on it, and
return the L{FilePath} of the path entry.'

def pathEntryWithOnePackage(self, pkgname='test_package'):

    entry = FilePath(self.mktemp())
    pkg = entry.child('test_package')
    pkg.makedirs()
    pkg.child('__init__.py').setContent('')
    return entry
