Re: [RFC PATCH 0/4] interpret-trailers: introduce "move" action

[Christian Couder <christian.couder@gmail.com>]

On Thu, Oct 5, 2017 at 3:22 PM, Paolo Bonzini <pbonzini@redhat.com> wrote:
> The purpose of this action is for scripts to be able to keep the
> user's Signed-off-by at the end.  For example say I have a script
> that adds a Reviewed-by tag:
>
>     #! /bin/sh
>     them=$(git log -i -1 --pretty='format:%an <%ae>' --author="$*")
>     trailer="Reviewed-by: $them"
>     git log -1 --pretty=format:%B | \
>       git interpret-trailers --where end --if-exists doNothing --trailer "$trailer" | \
>       git commit --amend -F-
>
> Now, this script will leave my Signed-off-by line in a non-canonical
> place, like
>
>    Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
>    Reviewed-by: Junio C Hamano <gitster@pobox.com>
>
> This new option enables the following improvement:
>
>     #! /bin/sh
>     me=$(git var GIT_COMMITTER_IDENT | sed 's,>.*,>,')
>     them=$(git log -i -1 --pretty='format:%an <%ae>' --author="$*")
>     trailer="Reviewed-by: $them"
>     sob="Signed-off-by: $me"
>     git log -1 --pretty=format:%B | \
>       git interpret-trailers --where end --if-exists doNothing --trailer "$trailer" \
>                              --where end --if-exists move --if-missing doNothing --trailer "$sob" | \
>       git commit --amend -F-
>
> which lets me keep the SoB line at the end, as it should be.
> Posting as RFC because it's possible that I'm missing a simpler
> way to achieve this...

Did you try using `--where end --if-exists replace --trailer "$sob"`?