Faster status checks for huge git repos

[yoavweiss]

The current status check for git repos can take several seconds when dealing with huge repos (WebKit in my case). It means a ~10 seconds delay for each command ran on the CLI.
Thanks to some twitter ranting, @paulirish and https://gist.github.com/3898739, I replaced git status with git diff.
AFAICT, diff based dirty/clean reports are identical to those of status, while being an order of magnitude faster (around 0.5 sec for the WebKit repo on my machine).

[gmiroshnykov]

Got a small regression: it won't report "dirty" status when a new untracked file is created.

[jtheoof]

It seems indeed much, much faster. I'll test a bit further and keep you posted if I find any bug.
I can confirm laggyluke comment: adding a new file, not tracked by git does not make the repo dirty.

[yoavweiss]

@laggyluke @jtheoof Thanks for pointing out that regression. I could not find a way to add untracked files to the dirty check while keeping it fast. OTOH, git status while ignoring untracked files (-uno) is even faster than git diff.

[robbyrussell]

Thanks for this. I'm unsure if I want to accept just yet. The untracked files as dirty is quite useful to me... hmm.

[jtheoof]

Is there any way to make it as an option? I agree that dirty untracked files could be useful but faster git status for large repo is too!

[robbyrussell]

@jtheoof / @yoavweiss if someone (nudge/wink) wants to add a way to disable considering untracked files as dirty to the .zshrc template, I'd consider that as a good way to approach this

[jtheoof]

Hi there, I've created a new pull request with option set up in zshrc.template see #1745
Right now it will only work for git but should be extensible to svn, hg and more for who knows about them.
Let me know if you have any comment.

[yoavweiss]

Thanks, @jtheoof ! Looks great :)