Git Bisect-Find

Ah! Finally a real world use for egg drop (with eggs and floors both equal to num commits since init, but maybe fewer eggs for those less patient).

For the algorithmically inclined, this is basically exponential search: <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Exponential_search" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Exponential_search</a>

if you don&#x27;t know what commit is good, just go way way way back. Go back 10,000 commits instead of 1,000. The magic of bisection search is that opening your search window by 10x only adds 3 (well, 3.332) extra bisections.

I scripted something similar at an old workplace;<p>Basically you&#x27;d pass a command to the script and it would track down the last commit that did not fail the command.<p>It&#x27;d search HEAD~4, HEAD~8, HEAD~16... until it found a good commit, then bisect.<p>The problem that I found is that bugs that have already been fixed still triggered in the past, and the only solution that I found to that was to branch the first buggy commit, apply a fix and squash and then rebase on top of that.<p>Not the best practice, but it saved me a lot of time.

&gt; Obviously jumping right to the first commit would reduce the number of git bisect-find steps. But would result in more git bisect.<p>Putting in a number of months&#x2F;years ago to start from would be a good middle ground.

&gt; I do wonder if jumping back by twice as much is optimal.<p>Some time ago, the idea came to me of weighting commits by diff size (as in LOC added + LOC removed, no thought to binary files), and using that to pick the halfway point for bisection. I&#x27;m not familiar with Git internals so I left it there. But I imagine that, while it wouldn&#x27;t make a huge difference in either case, it would benefit your tool more than it would a regular bisect.

Do people really use bisect in their professional life?<p>Can you sensibly use it without an enforcement of every PR being squashed, as otherwise you have not working, half baked commits all the time while bisecting? And you can’t compile, not even saying about stating if your bug is still reproducible or not.

&quot;2024&#x2F;05&#x2F;19&quot;, &quot;Posted in 30 days&quot;<p>Premature announcement?