Calculate time between git commits

Question

I would like to calculate the time between commits in git, this (I hope) will give me a rough measure of my productivity. Is this possible?

Answer 1

If you can send the output of git log to a file, then you're halfway there already. I'm not sure what language you're most comfortable with, but I know it's easy to do in a bash script.

Answer 2

This will print the date of the newer commit followed by the date of the older commit:

git log HEAD~[newer_commit] -n 1 --format=%ad; \
git log HEAD~[older_commit] -n 1 --format=%ad

You'll end up with date strings. Use whatever language you like to calculate the difference.

Answer 3

Here is a more complete example of using bash and date for doing this.

First, as noted in Git: want to iterate through all commits on branch, and list files in each commit :

git rev-list will list all revisions reachable from a given commit in reverse chronological order, so you can pass it a branch name to get the list for that branch head backwards

So, basically, the idea is that I use rev-list to iterate from HEAD backwards through the repo history, and at each revision, get the timestamp of current, and the timestamp of previous commit; get them as UNIX timestamps because then we can do integer arithmetic (difference) directly in bash; and finally use date to display the dates. So this bash script would be:

for ix in `git rev-list master`; do 
  thists=`git log $ix -n 1 --format=%ct`; 
  prevts=`git log $ix~1 -n 1 --format=%ct 2>/dev/null`; 
  if [ ! -z "$prevts" ] ; then 
    delta=$(( $thists - $prevts )); 
    echo `date -d @$thists +'%Y-%m-%d %H:%M:%S'` "-->"  \
         `date -d @$prevts +'%Y-%m-%d %H:%M:%S'` " ;= " \
         `date -d @$delta +'%H:%M:%S'`; 
  fi; 
done

Note that when you're at the first commit, there is no previous/parent commit, and so git log will fail with: fatal: ambiguous argument '45e95c7...~1': unknown revision or path not in the working tree.; to avoid printing this message, I redirect the stderr to /dev/null in the prevts command, and then do the time delta calculation only if prevts is not empty. The output from this script is something like this:

2017-08-27 09:44:04 --> 2017-08-26 17:12:22  ;=  17:31:42
2017-08-26 17:12:22 --> 2017-08-26 16:48:24  ;=  01:23:58
2017-08-26 16:48:24 --> 2017-08-26 16:28:05  ;=  01:20:19
...

However, these deltas are one hour off - so for more correct display of the time delta, I used Python's datetime.timedelta -- so in the above script, you may want to replace the `date -d @$delta +'%H:%M:%S'`; line with:

         `python -c "import datetime as dt; d = dt.timedelta(seconds=$delta); print(d)"`

... in which case this log is generated:

2017-08-27 09:44:04 --> 2017-08-26 17:12:22  ;=  16:31:42
2017-08-26 17:12:22 --> 2017-08-26 16:48:24  ;=  0:23:58
2017-08-26 16:48:24 --> 2017-08-26 16:28:05  ;=  0:20:19
...