config: don't assume ~/.sopel as dotdir

[dgw]

Infer config directory from given config filename. I found this branch kicking around while looking for something else… how I forgot about it for six months, I have no idea.

Resolves #1243 (@alanhuang122 please confirm 😅)

[alanhuang122]

I think I was reporting for someone in the channel. I don't really remember the justification anymore. If I'm not misreading the code, this would work by specifying -c <file> (as opposed to being interactive), which doesn't sound 100% correct, but I wasn't the one having the issue :v

[dgw]

Yeah, you were. I'm glad I keep my IRC logs, because it means #1243 (comment) now has the whole conversation that led to you opening the issue in the first place.

I don't know if this is actually enough, based on that added context, but there's certainly time to add a new argument in Sopel 7 (--home or something) if not. Sopel's probably always going to try for ~/.sopel if run without arguments that change the config dir, though. Something has to be the default…

[Exirel]

In #1429 I used a sopel.config.DEFAULT_HOMEDIR variable for the default home directory. I think it can be used here too.

[dgw]

@Exirel Want to drop a line note or two with suggested changes to show what you mean? Obviously I haven't touched this one in a while. 😅

[Exirel]

Over here: https://github.com/sopel-irc/sopel/pull/1429/files#diff-7fa6048ad26c4e738f57cc6ed66b156aR37

From my point of view, one of the issue faced by Sopel's code is that default variable and business rules (or behavior rules/features) are all over the places. So I thought it could be a good idea to put this default variable (here, the default location to Sopel's homedir) where it belongs, ie. in sopel.config.DEFAULT_HOMEDIR.

We recently discussed on IRC about reorganizing the code without any change in feature, and I think this is one example of how I would change things: making sure each feature has one and only place to define their rules.

[Exirel]

It also means that this:

dotdir = os.path.dirname(config) if config is not None else os.path.expanduser('~/.sopel')

Would become this:

dotdir = os.path.dirname(config) if config is not None else DEFAULT_HOMEDIR

[dgw]

That dotdir change is exactly what I thought it would be, thanks. :)

[dgw]

Rebased and tweaked to use DEFAULT_HOMEDIR in the spots where it seemed appropriate.

@Exirel does this look better now?

[Exirel]

LGTM