Re: [PATCH] commit: Optimize number of lstat() calls

> Aside from whitespace breakage, I think we should never skip the
> refreshing of the real index that is left after "git commit"
> finishes.
> 
> Between these two calls to refresh_cache(), the one that writes out
> a temporary index that contains the contents of HEAD plus the
> contents of the working tree for the specified paths may be fine
> without refreshing, unless somebody else (like the pre-commit hook)
> looks at it.  But the other one refreshes the real index file that
> will be used after "git commit" returns the control.  Users and
> scripts that run "git commit" inside expect that the entries in the
> resulting index are refreshed after "git commit" returns, and I do
> not think of a safe way to optimizing it out; unlike the other one,
> to which we can say "as long as there is no pre-commit hook, nobody
> will look at it after we are done", there does not an easy-to-check
> set of conditions that we can use to decide when it is safe to skip
> refreshing.
> 
> Besides, leaving the main index not refreshed would mean the user
> has to pay the refreshing cost when s/he runs other commands "git
> diff", "git status", etc. after "git commit" for the first time;
> so...