Re: renormalize histroy with smudge/clean-filter

From: brian m. carlson <sandals@crustytoothpaste.net>
Date: Feb 5, 2025, 22:55 UTC
Message-ID: <Z6PsXGnxM3UBR3nM@tapette.crustytoothpaste.net>
In-Reply-To: <20250205214726.GA30202@raven.inka.de>

On 2025-02-05 at 21:47:26, Josef Wolf wrote:

Show 11 quoted lines

> Hello all,
> 
> I have set up clean/smudge filters to normalzize files from an application to
> reduce the pain when those files are tracked by git.
> 
> The clean/smudge filter work well on new commit and the result of
> smudge+smudge+clean is the same as the result of a simple clean, so the filter
> should be fine IMHO.
> 
> But whenever I do any operations which introduce not yet normalized commits, I
> keep getting errors.

Yes, this is known to occur. It notably happens with Git LFS, which uses smudge and clean filters, and suffers from this same problem. Renormalizing is indeed the right solution.

Show 16 quoted lines

> So to get rod of those errors, I'd like to also renormalize the history:
> 
>   $ git rebase --root --strategy renormalize
>   error: Your local changes to the following files would be overwritten by
>   merge:
>         foo/bar/baz
>   Please commit your changes or stash them before you merge.
>   Aborting
>   $ git add foo/bar/baz
>   $ git commit -m renormalize foo/bar/baz
>   $ git rebase --continue
>   git: 'merge-renormalize' is not a git command. See 'git --help'.
>   error: could not apply abcdef... Foo Bar Baz
>   [ ... ]
> 
> Huh? I never entered a command "merge-renormalize"

When you use command like `--strategy foo` with a custom strategy, Git calls a binary called `git merge-foo` to implement that strategy. So while you didn't explicitly invoke that, when you used the nonstandard strategy `renormalize` (which, by the way, does not exist), Git invoked it when you rebased, since rebases by default use merges under the hood.

> BTW: It does not make any difference whether I add "-c merge.renormalze=true"

That option also does not exist. Can you tell us where you found such a recommendation? If we've been misleading people in our documentation, I'd like to fix.

> What would be the proper way to renormalize history?

The command that needs to be done is `git add --renormalize .` I think you probably want to do is something like this: `git rebase --root -x 'git add --renormalize . && git commit --amend --no-edit'`.

You might also be able to use `git filter-repo` to do this in a nicer way, but I'm not aware of how to do that. I've CCed the maintainer, however, in case he or anyone else can provide an answer.

-- 
brian m. carlson (they/them or he/him)
Toronto, Ontario, CA