Question

I am working on a program written by several folks with largely varying skill level. There are files in there that have never changed (and probably never will, as we’re afraid to touch them) and others that are changing constantly.

I wonder, are there any tools out there that would look at the entire repo history (git) and produce analysis on how frequently a given file changes? Or package? Or project?

It would be of value to recognize that (for example) we spent 25% of our time working on a set of packages, which would be indicative or code’s fragility, as compared with code that “just works”.

Answer 1

I wrote something that we use to visualize this information successfully.

https://github.com/bcarlso/defect-density-heatmap

Take a look at the project and you can see what the output looks like in the readme.

You can do what you need by first getting a list of files that have changed in each commit from Git.

~ $ git log --pretty="format:" --name-only | grep -v ^$ > file-changes.txt

~ $ for i in `cat file-changes.txt | cut -d"." -f1,2 | uniq`; do num=`cat file-changes.txt | grep $i | wc -l`; if (( $num > 1 )); then echo $num,0,$i; fi; done | heatmap > results.html 

This will give you a tag cloud with files that churn more will show up larger.