[Configobj-develop] Why does my config file behave this way?

[Jason B. <jb...@ze...>]

Here's a simplified version of a config file I'm using for envbuilder:

    [[sbcl]]
    setup = 'cp $CWD/customize-target-features.lisp $dir', 'sh make.sh', 'sh
install.sh'

$CWD is an option that I implicitly define at the toplevel to be the
directory from which envb is run, and $dir has a default.  Each item in this
list is a terminal command that's supposed to be part of a build process.

I'm getting some weird behavior that I suspect has to do with me using
validation and interpolation.  As it stands right now, setup isn't defined
in the configspec.  And so when I do the above, none of the values get
interpolated.  IE, the first command that gets issued is literally "cp
$CWD/customize-target-features.lisp $dir".  However, if I changed it to be a
single string, it works fine.  I can make this work properly if I add a
setup option in the configspec and set it to force_list.  Thus, this is
working for me.  I just want to get a better understanding of what's going
on here.  Can anyone shed some light on it?