Re: [PATCH] checkout: add --autostash option for branch switching

From: Phillip Wood <phillip.wood123@gmail.com>
Date: Mar 13, 2026, 14:29 UTC
Message-ID: <953b5842-a4ae-40f6-8cae-c4f81239c903@gmail.com>
In-Reply-To: <xmqqeclpi00y.fsf@gitster.g>

On 12/03/2026 14:40, Junio C Hamano wrote:

Show 14 quoted lines

> 
> Perhaps doing it this way would make it more worth doing?
> 
>   - At the beginning of branch switching, ask a new helper function
>     that takes the branch we are switching to as an argument this
>     question:
> 
>     Do any paths that are different between the current branch and
>     the branch we are switching to have local (i.e., either in the
>     index or in the working tree) change [Yes/No]?
> 
>   - When the answer is "yes", save the local changes to a new stash
>     entry, and clear the local changes from the index and from the
>     working tree.  If not, do not bother with stash at all.

Can we avoid the extra check and stash if the user passed "--autostash" and unpack_trees() fails because it would overwrite local changes in merge_working_tree()?

> If we can sell it as an improved implementation of "-m", we probably
> can lose some code that the current "-m" implementation uses to do
> its merge; we'd be instead using the "unstash" code paths.

That would be nice but I think "git checkout --recurse-submodules -m <branch>" currently updates submodules whereas "git stash" does not know how to recurse submodules.

It would be nice to teach "git stash" to recurse submodules but I don't think it is completly straight forward as we'd need to store the object id of the submodule's stash commit in the parent stash.

Thanks

Phillip