Git Pair

Easily attribute commits when pair programming!

Installation

1. Clone / copy this repository locally. Replace <GIT_PAIR_PATH> in the subsequent commands with the repository's absolute path (run pwd in the repository).

2. Set Git up to use the hooks provided by this project using core.hooksPath (don't worry, they're set up to still run local repository hooks):

   git config --global core.hooksPath '<GIT_PAIR_PATH>/githooks'

3. Create aliases:

   git config --global alias.pair '!<GIT_PAIR_PATH>/bin/git-pair'
   git config --global alias.solo '!<GIT_PAIR_PATH>/bin/git-solo'

Usage

When you start pairing, run

git pair $ALIAS

where $ALIAS is a memorable alias for the person you're pairing with (I recommend using their GitHub username). You can provide as many aliases at once as you like in the case you're pairing with more than one person.

If this is the first time pairing with someone, you'll be prompted to enter their name and email address. Use the values they want the commits attributed to. If you're using GitHub, you can also use their GitHub-provided no-reply email address and still get proper attribution.

Then write code and commit as normal. Your commit messages will have trailers like these appended to them:

Co-authored-by: name <name@example.com>
Co-authored-by: another-name <another-name@example.com>"

Make sure you leave a blank line between your commit message and any trailers.

When you're done pairing, run

git solo

to clear your pairs.

Note: pairs are per-repository. If you're working across more than one repository, you'll need to set up (and clear) your pairs in each one.

How it works

git pair creates a file, $GIT_DIR/current-co-authors, which stores the details of your co-authors.

Git looks into core.hooksPath for hooks. The hooks included in this repository all look for, and run, any executable hooks local to the Git repository you're working in, so any existing local hooks should continue to function as normal. The prepare-commit-msg hook looks in $GIT_DIR/current-co-authors, and adds co-author trailers to the commit message as the last step (so it will run after any local hooks).

git-solo then removes $GIT_DIR/current-co-authors, clearing any configured co-authors from future commits.

The first time you run git-pair for someone, it prompts you for their name and email address, which it stores in $HOME/.gitpairs. If an alias already exists there, git-pair will just use that data instead of prompting.

Possible improvements

• Make pairs editable. Currently, you have to manually edit $HOME/.gitpairs.
• Make amending a commit authored by someone else add the current Git user as a co-author.
• Create an installation script to simplify set up.