git-bayesect 1.0

Git bisection with Bayesian statistics

git bayesect

Bayesian git bisection!

Use this to detect changes in likelihoods of events, for instance, to isolate a commit where a slightly flaky test became very flaky.

You don't need to know the likelihoods (although you can provide priors), just that something has changed at some point in some direction

Installation

pip install git_bayesect

Usage

Start a Bayesian bisection:

git bayesect start --old $COMMIT

Record an observation on the current commit:

git bayesect fail

Or on a specific commit:

git bayesect pass --commit $COMMIT

Check the overall status of the bisection:

git bayesect status

Reset:

git bayesect reset

More usage

Set the prior for a given commit:

git bayesect prior --commit $COMMIT --weight 10

Set prior for all commits based on filenames:

git bayesect priors_from_filenames --filenames-callback "return 10 if any('suspicious' in f for f in filenames) else 1"

Set the beta priors:

git bayesect beta_priors --alpha-new 0.9 --beta-new 0.1 --alpha-old 0.05 --beta-old 0.95

Get a log of commands to let you reconstruct the state:

git bayesect log

Undo the last observation:

git bayesect undo

Run the bisection automatically using a command to make observations:

git bayesect run $CMD

Checkout the best commmit to test:

git bayesect checkout

How it works

TODO: talk about math