title: Git bisect automation

date: 2020-11-12 2

layout: post

lang: en

ref: git-bisect-automation

eu_categories: git

It is good to have an standardized way to run builds and tests on the repository of a project, so that you can find when a bug was introduced by using git bisect run.

I've already been in the situation when a bug was introduced and I didn't know how it even was occurring, and running Git bisect over hundreds of commits to pinpoint the failing commit was very empowering:

$ GOOD_COMMIT_SHA=e1fd0a817d192c5a5df72dd7422e36558fa78e46
$ git bisect start HEAD $GOOD_COMMIT_SHA
$ git bisect run sn -c './build.sh && ./run-failing-case.sh'

Git will than do a binary search between the commits, and run the commands you provide it with to find the failing commit.

Instead of being afraid of doing a bisect, you should instead leverage it, and make Git help you dig through the history of the repository to find the bad code.