Re: [PATCH] completion: complete remote branches with switch --track

From: Jacob Keller <jacob.keller@gmail.com>
Date: Apr 23, 2020, 23:46 UTC
Message-ID: <CA+P7+xqgW0tfLcy8R4gy2X_8apvXOaibvd3XWWdKSk8yMi+4Bg@mail.gmail.com>
In-Reply-To: <20200423020344.GI140314@google.com>

On Wed, Apr 22, 2020 at 7:03 PM Jonathan Nieder <jrnieder@gmail.com> wrote:

>
> Let me check that I understand correctly:
>

I do not believe your understanding here is correct. This is about the case where you try to complete

git switch --track <TAB>

I expect this to complete to the list of all remote branches, and *not* to include local branches that already exist.

Today, on git version 2.25.2,

git switch --track <TAB> completes only to local branches.

git switch <TAB> appears to complete to basically any reference.

> If --detach is passed, the <start-point> parameter is an arbitrary
> commit.  So we want all refs (or even all commits), not just commits
> that are eligible for "git switch --guess" (the default mode) dwimery.
>

Yep, I agree here.

Show 5 quoted lines

> If --track is passed, the <start-point> parameter should be an
> arbitrary remote-tracking branch, not just a remote-tracking branch
> without corresponding local branch that would be eligible for --guess.
> A few lines up we handle this by setting track_opt to empty.
>

Sort of. Yes, we do disable "track_opt", but, because --detach is *not* set, we also set only_local_ref=y.

In this case, when only_local_ref=y, and when track_opt is not set, we trigger the call to __git_heads instead of __git_complete_refs.

I *think* the problem is that we actually got something inverted in a sense:

We probably do want git switch to complete only local branches and dwims, not arbitrary references.

Show 11 quoted lines

> If neither --detach nor --track is passed, then...
>
> ... I'm not sure I understand the neither --detach nor --track passed
> case.  Wouldn't this be --guess mode, where "$track_opt" is set, so the
> value of "$only_local_ref" isn't used?  Or is this about the case
> where (1) --detach is not passed, (2) --track is not passed, and (3)
> --no-guess or GIT_COMPLETION_CHECKOUT_NO_GUESS is passed?
>
> Yes, it must be about that case.  In that case, only_local_ref is
> right.
>

that seems to behave properly, i.e.

git switch --no-guess <TAB> will complete only local branches.

> In any case, this is getting difficult to understand, so I wonder if
> some refactoring is in order.
>

The trouble here is that we accidentally trigger that behavior if you do

git switch --track

because we set track_opt to none, *and* we set only_local_refs to y, resulting in just calling git_heads.

I think the trouble is that __git_complete_refs prints far more than we want, so it needs some new options to avoid printing certain settings.

I *think* the problem is that --dwim lists *both* local refs *and* unique branches from remotes, and because it lists local references, we end up displaying a bunch of unnecessary refs like tags and such.

Hmm.

Thanks, Jake