Re: Can't checkout branch

From: Chris Torek <chris.torek@gmail.com>
Date: Jul 14, 2020, 18:17 UTC
Message-ID: <CAPx1GvcOpmpuPseAQDYk9pg+hfdF9KJSSSiB0fEHQrnUuPS4CA@mail.gmail.com>
In-Reply-To: <CACwCsY7P5NiQL5ajHMOWo2EPiQZKUj_m_AVbtGy=z=twChimjw@mail.gmail.com>

On Tue, Jul 14, 2020 at 10:04 AM Larry Martell <larry.martell@gmail.com> wrote: [snippage]

Show 18 quoted lines

> $ git fetch --all
> Fetching origin
>  * [new branch]      deploy     -> origin/deploy
>
> $ git checkout deploy
> $ git branch
> * master
>
> $ git checkout origin/deploy
> Note: checking out 'origin/deploy'.
>
> You are in 'detached HEAD' state.
>
> I tried deleting the local repo and recloning, but I got the same
> results. I see the branch on github. I can checkout other branches,
> just not this one.
>
> What could be going on?

This happens in Git versions prior to 2.23 (what Git version are you using?) when there is a *file or directory* named `deploy`.

What is happening is that since there is no *branch* named deploy (yet), you can't check it out (yet). So `git checkout deploy` initially fails. The checkout command then goes on to try two alternatives:

 1. Treat this as `git checkout -- deploy`, i.e.,
    extract the file or subtree named `deploy` from
    the index (discarding changes to that file or
    subtree).

 2. Treat this as `git checkout -b deploy origin/deploy`
    or `git checkout -t origin/deploy`, i.e., create the
    branch `deploy` from `origin/deploy`.

If *both* of these alternatives work, pre-2.23 Git *assumes* you meant alternative number 1. In 2.23 or later, `git checkout` tells you that this is ambiguous and makes you pick which one you want.

To work around this in all versions of Git, you can just be more explicit. For instance:

    git checkout deploy --

forces Git to treat it as a branch name.

Chris