Re: [PATCH] Do not ignore hidden refs

Petr Baudis <pasky@suse.cz> writes:

refs.c::check_ref_format() seems to suggest that any ref whose path component begins with a dot is invalid (since October last year), so I am a bit surprised you are bringing this up now. Do you know of specific examples where this is not enforced? It could even be argued that the places in the system that allow such a ref are buggy.

I do not recall why we decided that this particular restriction was needed (I do understand the other three restrictions --- see commit log of 03feddd6), although I do think this is not a gratuitous change but comes from a list discussion. I suspect it was to avoid confusion with ".." operator ("..." was added much later in July this year), but it is not consistent that we do not forbid the ones that end with a dot.

Maybe we should have found this inconsistency and added "names that end with a dot" to the forbidden category when we introduced the symmetric difference, but apparently nobody noticed. Right now foo...bar is seriously ambiguous. Even though it cannot be "foo" .. ".bar" (because ".bar" is not a valid refname), it can be "foo." .. "bar" or "foo" ... "bar", and worse yet spelling longhand form "refs/heads/foo." does not help to disambiguate this.