Re: [BUG] b4: assertion error with `b4 send`

On Thu, Jun 04, 2026 at 10:23:39PM +0200, Andreas Hindborg wrote:
> Hi,
> 
> I got this assertion error when sending patches today:
> 
> ---
> Sent 11 messages
> Tagging sent/20250305-unique-ref-29fcd675f9e9-v17
> Recording series message-id in cover letter tracking
> Created new revision v18
> Updating cover letter with templated changelog entries.
> Invoking git-filter-repo to update the cover letter.
> New history written in 0.06 seconds...

[...]

>   File "/nix/store/xl7fx5x8g52g03npg1dpjzvaiijpv98z-python3.13-git-filter-repo-2.47.0/lib/python3.13/site-packages/git_filter_repo.py", line 4767, in _record_metadata
>     self._compute_metadata(metadata_dir, orig_refs)
>     ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^
>   File "/nix/store/xl7fx5x8g52g03npg1dpjzvaiijpv98z-python3.13-git-filter-repo-2.47.0/lib/python3.13/site-packages/git_filter_repo.py", line 4712, in _compute_metadata
>     assert(usoa == intermediate) # old wasn't pruned => usoa == intermediate

Looks like this tripped something in git-filter-repo, so not something we
control anyway.

> It looks like everything is OK and b4 set up for the next spin, cover
> letter looks right.

Yes, looks like it was during some kind of cleanup.

> I observed this on nixos first with b4 0.14.3 via nixpkgs 25.05, then
> upgraded to 0.15.2 via nixpkgs unstable.

We actually got rid of git-filter-repo in the latest master, so I'm just going
to blame this on gremlins and blame the alignment of the celestial spheres. :)

-K