Here's an odd thing about the
git bisect command: It has only 1 option
(--no-checkout). Compare with eg
git commit, which has 36 options by my
The difference is largely down to git having a pervasive culture of
carefully edited history. We need lots of
git commit options to carefully
produce commits that look Just Right. Staging only some of the files we've
edited, perhaps even staging only some of the changes within a file. Amend
that commit if we notice we made a mistake. Create a whole series of beautiful
commits, and use rebase later to remix them into a more beautiful whole.
Beautiful fake histories. Because coding is actually messy; our actual edit history contains blind alleys and doublings back on itself; contains periods of many days the code isn't building properly. We want to sweep that complexity away, hide it under the rug. This works well except when it doesn't, when some detail airbrushed out of the only remaining history turns out to be important.
Once we have these beautiful fake histories of changes, we can easily bisect them and find the commit that introduced a bug. So bisect doesn't need a lot of options to control how it works.
I'd like to suggest a new option though. At least as a thought experiment. --merges-only would make bisect only check the merge commits in the range of commits being bisected. The bisection would result in not a single commit, but in the set of commits between two merges.
I suspect this would be useful for faster bisecting some histories of the beautiful fake kind. But I know it would be useful when the history is messy and organic and full of false starts and points where the code doesn't build. Merges, in such histories, are often the points where things reach a certian level of beauty, where that messy feature branch got to the point it all built again (please let this happen today) and was merged into master. Bisecting such points in a messy organic history should work about as well as bisecting carefully gardened histories.
I think I'll save the full rant about beautiful fake history vs messy real history for some other day. Or maybe I've already ranted that rant here before, I can't remember.
Let's just say that I personally come down on the side of liking my git history to reflect the actual code I was working on, even if it was broken and even if I threw it away later. I've indeed taken this to extreme lengths with propellor; in its git history you can see every time I've ever run it, and the version of my config file and code at that point. Apologies to anyone who's been put off by that... But oddly, propellor gets by far more contributions from others than any of my other haskell programs.
All in the form of beaufiully constructed commits, naturally.