Automate commit co-authors when pairing
Pairing is a fantastic way to quickly bounce ideas around, get help with
something, or even as a tool for mentoring and growth. In recent times,
most Git-based tools have adopted the Co-Authored-By
trailer
to identify when there are multiple authors to a commit. This is great, but
often a pain to type out manually, especially if there are many commits or
multiple people involved.
Asking around at work, there were a few things people had — everything from vim macros, to custom shell functions — but nothing quite like what I wanted. So I wrote a script to do it for me.
It begins with git-pair
(to be used as git pair
).
This script enumerates all the commit authors in the current repo, offers
them to you with a fuzzy-finder,
and then appends those people as co-authors on every commit until you run a
companion script to end the session.
#!/usr/bin/env bash set -uf -o pipefail TEMPLATE_PATH="$HOME/.config/git/template" TRAILERS="" while true ; do pick="$(echo -e "$(git shortlog -e -s | cut -f2)" | fzy)" if [[ "$pick" != "" ]]; then TRAILERS+="Co-authored-by: $pick\n" echo "Added co-author: $pick" else break fi done if [[ "$TRAILERS" != "" ]] ; then echo -e "\n" > $TEMPLATE_PATH echo -e "$TRAILERS" >> $TEMPLATE_PATH echo "π§βπ»Pairing mode enabled. Run 'git unpair' to end session." fi
This uses Git's "commit template" feature to hack in the trailers for us automatically on each commit. This requires you to have a bit of Git configuration to point it at a template file:
[commit] template = ~/.config/git/template
Unfortunately, as of 2.32 at least, template files need to exist at all times, even if they are empty. Make sure to touch it before proceeding to keep Git happy.
As you may have noticed, we also will want git-unpair
to end a
pairing session. This script is much simpler, however, as "ending a
session" really just means "emptying the commit template."
#!/usr/bin/env bash set -euf -o pipefail echo > "$HOME/.config/git/template" echo "π Disabled pairing mode."
One quick other feature, however: what if you're pairing with someone who doesn't have commits in the current repo? Well, we can supplement the commit author list with a static list of "known colleagues" so that even in a blank git repo we have a list of people to choose from.
TEMPLATE_PATH="$HOME/.config/git/template" +if [[ -e "$HOME/.colleagues.txt" ]] ; then + COLLEAGUES="$(cat $HOME/.colleagues.txt)" +else + COLLEAGUES="" +fi TRAILERS="" while true ; do - pick="$(echo -e "$(git shortlog -e -s | cut -f2)" | fzy)" + pick="$(echo -e "$COLLEAGUES\n$(git shortlog -e -s | cut -f2)" | uniq | fzy)" if [[ "$pick" != "" ]]; then
Then you can automate or manually maintain ~/.colleagues.txt
,
which should be a plain text list of Name <email>
lines.
We pass everything through uniq
as well, to make sure any
people in both lists only get one entry.
With all of that in place, you can now pair! It should be as easy as:
git pair
- Fuzzy-select people (hit
^D
when done) - Make some commits
git unpair
Hopefully this makes your pairing sessions easier, with significantly less awkward typing of trailers after every commit. The full source of the script, and all my other scripts and configuration, are in my dotfiles repository.
Happy pairing π§βπ»β¨