Re: commit-message attack for extracting sensitive data from rewritten Git history

> With or without the security issue, leaving old object names that
> will become irrelevant in the rewritten history will make the
> resulting history less useful, simply because people cannot look at
> the objects these messages refer to. The same argument is behind the
> reason why "cherry-pick -x" was originally the default, found to be
> a mistake and made optional.
> 
> filter-branch provides "map" helper function to help mapping old
> object names to rewritten object names, but stops there; it leaves
> it up to the message filter script to identify what string in the
> message is an object name to be rewritten.
> 
> It can be taught to be more helpful to the message filter writers,
> and you seem to have done so in BFG, which is very good.