#!/bin/sh
# SPDX-License-Identifier: MIT
set -eu
export TZ=UTC LC_ALL=C
export GIT_CONFIG_NOSYSTEM=1 GIT_CONFIG_GLOBAL=/dev/null
export GIT_AUTHOR_NAME='Example Author' GIT_AUTHOR_EMAIL='author@example.invalid'
export GIT_COMMITTER_NAME='Example Author' GIT_COMMITTER_EMAIL='author@example.invalid'
export GIT_AUTHOR_DATE='2026-10-27T12:00:00+00:00'
export GIT_COMMITTER_DATE='2026-10-27T12:00:00+00:00'
test "$(git version)" = 'git version 2.56.0'

mkdir revert-example
cd revert-example
git init --template= --bare -q --initial-branch=main origin.git
git init --template= -q --initial-branch=main writer
cd writer
printf 'original\n' > note.txt
git add note.txt
git commit -qm 'Base'
git remote add origin ../origin.git
git push -q -u origin main >/dev/null
printf 'shared change\n' >> note.txt
git commit -qam 'Shared change'
git push -q origin main
shared=$(git rev-parse HEAD)
printf '#!/bin/sh\nexit 0\n' > ../editor.sh
chmod +x ../editor.sh
GIT_EDITOR=../editor.sh git revert HEAD >/dev/null
git merge-base --is-ancestor "$shared" HEAD
test "$(cat note.txt)" = original
test "$(git rev-list --count HEAD)" = 3
printf 'Revert made a new commit; shared commit remains an ancestor\n'
git push -q origin main
test "$(git rev-parse HEAD)" = "$(git --git-dir=../origin.git rev-parse refs/heads/main)"
printf 'Local bare remote received the new revert commit\n'