Counting your contribution to a git repository

Disclaimer: The views expressed here are my own; they do not reflect the views of my current and past employers.

Sometimes you may wonder, how many commits or lines of code did I contributed to a git repository? Here are some easy one liners to help you count that.

Number of commits

Let’s start with the easy one: counting the number of commits made by one user.

The easiest way is to run

git shortlog -s

This gives you a list of commit counts by user:

2  Grant Lindberg
9  Jonathan Hao
2  Matias Kinnunen
65  Shing Lyu
4  Shou Ya
1  wildsky
1  wildskyf

(The example comes from shinglyu/QuantumVim.)

If you only care about one user you can use

git rev-list HEAD --author="Shing Lyu" --count 

, which prints 65.

Let’s explain how this works:

• git rev-list HEAD will list the commit objects in HEAD
• --author="Shing Lyu" will filter out only the commits made by the author Shing Lyu
• --count counts the number of commits. You can pipe it to | wc -l instead.

Count the line of insertion and deletions by a user

Insertion and deletions are a little bit tricker. This is what I came up with:

git log --author=Shing --pretty=tformat: --numstat | grep -v '^-' | awk '{ add+=$1; remove+=$2 } END { print add, remove }' 

This might seem a little bit daunting, but we’ll break it up into steps:

• git log --author="Shing Lyu" list the commits by Shing Lyu, in the following format:

  commit 6966b2c969cbf62029792221bf124ed75ee2c640
  Author: Shing Lyu <shing.lyu@gmail.com>
  Date:   Sat Nov 18 17:01:25 2017 +0100
  
      Added Ctrl+z to close all system tabs
  
  commit f4710cc3a2efdc63c7caf3ec04d504912ad20a93
  Author: Shing Lyu <shing.lyu@gmail.com>
  Date:   Sat Nov 18 15:58:20 2017 +0100
  
      Bump version and diable jpm packaging
  

• --numstat will give us the line added and removed per file per commit:

  commit 6966b2c969cbf62029792221bf124ed75ee2c640
  Author: Shing Lyu <shing.lyu@gmail.com>
  Date:   Sat Nov 18 17:01:25 2017 +0100
  
      Added Ctrl+z to close all system tabs
  
      1       0       README.md
      10      0       manifest.json
      6       1       package.sh
      35      0       vim-background.js
      4       1       vim.js
  
  commit f4710cc3a2efdc63c7caf3ec04d504912ad20a93
  Author: Shing Lyu <shing.lyu@gmail.com>
  Date:   Sat Nov 18 15:58:20 2017 +0100
  
      Bump version and diable jpm packaging
  
      1       1       manifest.json
      3       3       package.sh
  

• We don’t really need the commit, Author, Date and commit message fields, so we use an empty formatting string to get rid of them: --pretty=tformat:

  1       0       README.md
  10      0       manifest.json
  6       1       package.sh
  35      0       vim-background.js
  4       1       vim.js
  1       1       manifest.json
  3       3       package.sh
  

• If you add some non-text files, e.g. png image files, the insertion/deletion count might be represented as - - foo.png. Therefore we filter them out with grep -v '^-'. If you are not familiar with grep, -v means reverse match (i.e. find those lines that does NOT match the patter). The pattern ^- means lines staring with a -. (This part is optional if you pipe to awk, awk seems to ignore non-numeric character while doing the math.)

• Finally we pipe it to awk for summing. Even if you are not familiar with awk, this part is pretty self-explanatory:

  awk '{ add+=$1; remove+=$2 } END { print add, remove }'
  

  We add column one ($1) to the variable add, and column two ($2) to the variable remove, then we print them out. This gives us an output like so:

  936 260 
  

Other alternatives

There are many other off-the-shelf scrips that will help you calculate contribution statistics. Like git-quick-stats, git-fame and git-fame-rb. But if you only want a quick-and-easy solution please give it a try.