alexpopov/git-prev-next

Git Prev/Next - Interactive Commit Stack Walker

Overview

git prev and git next are custom scripts (in ~/.local/bin/) that let you walk backward and forward through a commit stack, pausing at each commit in an editable state. Under the hood they manage an interactive rebase automatically.

This is simpler and safer than manually running git rebase -i when you need to amend multiple commits in sequence.

How It Works

• git prev — moves HEAD to the parent commit (goes backward in history). If not already in an interactive rebase, starts one automatically.
• git next — moves HEAD to the next commit (goes forward in history). Only works when already in an interactive rebase (started by git prev).
• Both accept an optional count argument: git prev 3 moves back 3 commits.
• At each stop, HEAD is in "edit" mode — you can amend the commit, stage changes, or inspect it.
• When done, use git rebase --continue to finish replaying remaining commits.

Requirements

• Working tree must be clean before using git prev.
• Does not support merge commits.
• Does not support non-interactive rebases (.git/rebase-apply).

Common Workflows

Amend a series of commit messages

For example, adding Differential Revision: lines to 5 commits:

# Start at the top of your stack
git log --oneline -5

# Walk to the bottom commit you want to edit (use count to skip multiple)
git prev 4        # go back 4 commits at once

# At each commit, amend the message using the temp file approach
git log -1 --format=%B > /tmp/commitmsg.txt
echo "" >> /tmp/commitmsg.txt
echo "Differential Revision: https://phabricator.intern.facebook.com/DXXXXXXX" >> /tmp/commitmsg.txt
git commit --amend -F /tmp/commitmsg.txt
rm /tmp/commitmsg.txt

# Move forward to next commit
git next

# Amend that one too (same temp file pattern)
git log -1 --format=%B > /tmp/commitmsg.txt
# ... edit /tmp/commitmsg.txt ...
git commit --amend -F /tmp/commitmsg.txt
rm /tmp/commitmsg.txt

# Repeat git next + amend for each commit, then finish
git rebase --continue

Make code changes to an older commit

git prev 2                          # walk back 2 commits
# make your edits...
git add <files>
git commit --amend --no-edit        # fold changes into this commit
git next                            # move forward (may need conflict resolution)
git rebase --continue               # finish

Important Notes

• Run git status often to remind yourself you're in a rebase. It's easy to forget, especially across tool calls or context switches. git status will show interactive rebase in progress when you're mid-walk.
• git prev uses git reset --hard HEAD^ internally — ensure your work tree is clean before using it.
• git next calls git rebase --continue internally — conflicts may arise if your amendments change code that later commits touch.
• When you're done editing, you must git rebase --continue to replay any remaining commits. If you forget, you'll be left in a detached HEAD state with a .git/rebase-merge directory.
• The remaining commits to replay are listed in .git/rebase-merge/git-rebase-todo. This file shows what's queued but do NOT edit it directly — use git prev, git next, and git rebase --continue to control the flow.
• git prev from a non-rebase state starts a new interactive rebase on HEAD^. git next from a non-rebase state prints "At top" and exits.