November 2, 2025
Bisect and the City
At the end you use Git bisect
Dev drama: 'magic' Git tool finds the bad change, but commenters blame process
TLDR: A developer used Git’s bisect feature—basically binary search—to pinpoint the commit that broke tests and quickly fix it. The comments erupt: some applaud the trick, others say good testing and cleaner history should prevent this, while a few admit they’ve been debugging by hand.
A developer tells a tale: tests suddenly went red in a massive “one repo for everything” setup, and nobody could find the culprit. Enter git bisect — a feature that uses binary search (think: halving the suspects until you find the villain) to pinpoint the exact bad change. The punchline? It nailed the offending commit and the world turned green again. Cue the crowd.
Some readers were unimpressed. huflungdung essentially rolled their eyes: binary search isn’t exotic, it’s basic. Meanwhile, lloydatkinson dropped a spicy truth bomb: this is “really a workaround for having a poor process,” arguing better unit tests and CI/CD (continuous integration and delivery—robots that run checks on every change) should have caught it. rf15 took it further, saying optimizing the easy part (when a bug is reproducible) “seems misapplied.” On the other side, dpflan shouted “git-bisect is legit,” while kfarr confessed they’ve been doing commit hunting manually for years, sparking memes of cavemen discovering wheels.
Bonus drama: a history nerd-off erupted over how teams record changes—squash-and-merge (condense history) versus keeping every commit. Fans of bisect say it’s like CSI for code; skeptics say it’s duct tape for messy workflows. And yes, someone dropped the LeetCode ‘First Bad Version’ meme, because prophecy fulfilled.
Key Points
- •Git bisect applies binary search to identify the commit that introduced a failing test.
- •A monorepo test failure was traced to a configuration change referencing a different account for a remote token.
- •Selecting known good and bad commits allows bisect to automate narrowing down the offending change.
- •A demo with Python and pytest shows a bad commit changing numeric addition to string concatenation.
- •git bisect run uses a script returning exit codes to automatically classify commits as good or bad.