On Fri, Jun 13, 2025 at 1:58 PM [off-list ref] wrote:

[...]

This bug was introduced in e9c1b0e3 (revision: improve
commit_rewrite_person(), 2022-07-19) when the much simpler version of
commit_rewrite_person() that worked on one "person header" at a time
was rewritten to use the current apply_mailmap_to_header() function.
The original implementation processed author and committer separately,
but the rewrite introduced this loop-based approach that failed to
properly handle the transition between identity lines.

Thanks for adding this context and improving the `sed` invocation in
the tests! Happy to stand behind this change too :-)