Counting your contribution to a git repository

Disclaimer: This content reflects my personal opinions, not those of any organizations I am or have been affiliated with. Code samples are provided for illustration purposes only, use with caution and test thoroughly before deployment.

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.