Find your possible co-authors for your next commit using ripgrep and babashka

When it comes to fairness, acknowledging the help or time your colleagues contribute is crucial. One simple way to ensure proper attribution is by adding co-authors to your commits.

To add co-authors, include one or more Co-authored-by trailers at the end of your commit message, like this:

Commit message

Co-authored-by: Joel Califa <602352+califa@users.noreply.github.com>
Co-authored-by: Matt Clark <44023+mclark@users.noreply.github.com>

With basic Unix tools

No fire, no flames, just the basic Unix tools you already have on your system:

$ alias git-co-authored-by="git log &> /dev/null && git log --shortstat | grep \"Author:\" | sed \"s/Author: //\" | sort -u | sed \"s/^/Co-authored-by: /\""

With ripgrep and babashka 🚀

Make sure to include these trailers after at least one blank line at the end of your commit message.

For added convenience, you can set up a helpful alias in your shell environment (e.g., .bash_aliases, .zsh_aliases, or similar). Here’s a quick example:

$ git log &> /dev/null && git log --shortstat | head -n 10000 | rg "Author:" | bb -i -o '(map #(clojure.string/replace % #"Author: " "Co-authored-by: ") (set *input*))'

Requirements

Here are the two tools you need to have installed, check out their official documentation:

babshka
ripgrep on Github

Explanation of the clojure code

Let’s break down the babashka command bb -i -o '(map #(clojure.string/replace % #"Author: " "Co-authored-by: ") (set *input*))':

1. bb - This is the babashka CLI command
2. -i - Flag that tells babashka to read from standard input
3. -o - Flag that tells babashka to write to standard output
4. The main expression consists of several nested operations:
   • (set *input*) - Converts the input lines into a set, removing duplicates
   • (map ...) - Applies a function to each element in the set
   • The function #(clojure.string/replace % #"Author: " "Co-authored-by: ") does the following:
     • Uses clojure.string/replace to perform string replacement
     • % is a placeholder for each input item
     • #"Author: " is a regex pattern matching “Author: “
     • "Co-authored-by: " replaces for the matched pattern

In plain English: This command reads lines from standard input, removes duplicates, and then removes the text “Author: “ from the beginning of each remaining line.

Example usage:

$ echo -e "Author: John\nAuthor: Jane\nAuthor: John" | bb -i -o '(map #(clojure.string/replace % #"Author: " "Co-authored-by: ") (set *input*)))'

Output:

Co-authored-by: John
Co-authored-by: Jane

Wrapping the script up

Running git log &> /dev/null first ensures you avoid system errors when executing the command.

To make sure you have the necessary tools, install them using Homebrew or Linuxbrew with the following command:

$ brew install borkdude/brew/babashka ripgrep

Happy Pair-Programming!