Subject: Re: [PATCH 5/6] completion: list existing working trees for 'git worktree' subcommands

From: SZEDER Gábor <[email-masked]>
Date: Fri, 18 Oct 2019 17:00:06 +0200

On Thu, Oct 17, 2019 at 02:08:12PM -0400, Eric Sunshine wrote:
> On Thu, Oct 17, 2019 at 1:35 PM SZEDER Gábor <[email-masked]> wrote:
> > Complete the paths of existing working trees for 'git worktree's
> > 'move', 'remove', 'lock', and 'unlock' subcommands.
> > [...]
> > Arguably 'git worktree unlock <TAB>' should only complete locked
> > working trees, but 'git worktree list --porcelain' doesn't indicate
> > which working trees are locked.  So for now it will complete the paths
> > of all existing working trees, including non-locked ones as well.
> 
> It is a long-standing To-Do[1] for "git worktree list [--porcelain]"
> to indicate whether a worktree is locked, prunable, etc. Looking at
> the implementation of builtin/worktree.c:show_worktree_porcelain(), it
> should be easy enough to add.

I didn't look at the implementation, but only at the docs, which says:

  --porcelain
      With list, output in an easy-to-parse format for scripts. This
      format will remain stable across Git versions and regardless of
      user configuration. See below for details.

I'm not sure whether introducing a new boolean attribute (i.e. a line
containing only "locked") would still be considered acceptable, or
would count as changing the format.  I can imagine that a too strict
parser would barf upon encountering the unrecognized "locked"
attribute; but yeah, no sensible parser should be that strict IMO.

Furthermore, I'm not sure what to do with the reason for locking.  In
general I would think that it makes sense to display the reason in an
easy-to-parse format as well.  However, doing so will inherently make
the format less easy to parse, because the reason could span multiple
lines, so without some sort of encoding/escaping it would violate the
"a line per attribute" format.

I would say that this is beyong the scope of this patch series :)

> > diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
> > @@ -2981,10 +2981,21 @@ _git_whatchanged ()
> > +__git_complete_worktree_paths ()
> > +{
> > +       local IFS=$'\n'
> > +       __gitcomp_nl "$(git worktree list --porcelain |
> > +               sed -n -e '2,$ s/^worktree //p')"
> > +}
> 
> I know that the commit message talks about it, but it might deserve an
> in-code comment

OK.