bugspots

What is bugspots?

Bugspots is a Python implementation of the bug prediction algorithm used at Google. It also embed a command-line interface which can be used to list the "hot spots" of a Git repository.

What is a hot spot?

A hot spot is merely a file that is bug-prone.

How does it work?

The algorithm is very simple and to the point: it gives each file a score based on its number of bug-fixing commits and their age, and then return a descending-ordered list of the files based on their score, filtering commits that are no longer at HEAD.

What is a bug-fixing commit?

Any commit whose purpose is to fix an issue. They are identified by message, using the same pattern as GitHub, which is:

(?i)(fix(e[sd])?|close[sd]?) #[1-9][0-9]*

What is the formula used?

$\textrm{score}{\left(i\right)}=\sum_{i=0}^n\frac{1}{1+e^{\left(-12t_i+12\right)}}$

where t_i is the timestamp of the ith commit, normalized between 0 and 1 (0 being the date of the first commit in the repository and 1 being the date of the last commit in the repository), and n is the number of bug-fixing commits.

Installation

$ pip install bugspots

Command-line usage

$ bugspots.py -h

Python example

import bugspots
b = bugspots.Bugspots()
for hotspot in b.get_hotspots():
    print " %6.3f %s" % (hotspot.score, hotspot.filename)

sprt/pybugspots