During code review at a later time, the history of the experimentation is useless once you find several commits that touch the same code before settling on a final version.
I think this whole debate hinges on peoples' view of that sentence. Sometimes clean history helps comprehensibility and sometimes it obscures things. I think the amount to which each is true varies author to author, reader to reader, and project to project.
Prescient observation. How does clean history obscure things though? You mean as failed experiments get removed? Important things ought to be mentioned in commit messages. Relevant things to document can be showcased like "Tried X but it turns out Y is better because Z." I often find that code alone is not enough to describe why something did or didn't work. One ends up having to explain in commit messages anyway.
Me too. And I also often find that commit messages alone are not enough to describe why something did or didn't work. Code and commit messages both help.
"Clean history" can obscure things when it leaves out information about the often messy process of creating the software. It's impossible to know ahead of time what information will and will not be useful when attempting to grok a piece of code in the future, so sometimes it makes sense to err on the side of more information, instead of less.
Really? That seems like an extraordinarily obtuse way to understand code. I would think comments directly the source files would be more useful. Commit history shows how they arrived at that result and that's what I would rather see there.
- a = 1;
- a = 7;
- a = 3;
or
2) one commit that says:
a = 3;
My point is that experimentation is slightly different from changing your mind about the whole implementation. It is the same as writing your homework. You have a separate piece of paper where you make your experiments.
_All the time_. I read all the commits in the codebase I'm responsible for. I need to keep track of what people are doing and how the system is changing. This is also on top of the need for code review and ensuring each patch is correct.
Check out http://en.wikipedia.org/wiki/Atomic_commit#Atomic_Commit_Con...