Re: Should "head" also work for "HEAD" on case-insensitive FS?

From: Konstantin Khomoutov <kostix+git@007spb.ru>
Date: Jul 4, 2017, 07:19 UTC
Message-ID: <20170704071909.phs4bf5ybdord2lv@tigra>
In-Reply-To: <87ziclb2pa.fsf@gmail.com>

On Tue, Jul 04, 2017 at 12:00:49AM +0200, Ævar Arnfjörð Bjarmason wrote:

Show 13 quoted lines

> I don't have a OSX box, but was helping a co-worker over Jabber the
> other day, and he pasted something like:
> 
>     $ git merge-base github/master head
> 
> Which didn't work for me, and I thought he had a local "head" branch
> until realizing that of course we were just resolving HEAD on the FS.
> 
> Has this come up before? I think it makes sense to warn/error about
> these magic /HEAD/ revisions if they're not upper-case.
> 
> This is likely unintentional and purely some emergent effect of how it's
> implemented, and leads to unportable git invocations.

JFTR this is one common case of confusion on Windows as well. To the point that I saw people purposedly using "head" on StackOverflow questions. That is, they appear to think (for some reason) that branches in Git have case-insensitive names and prefer to spell "head" since it (supposedly) easier to type.

I don't know what to do about it. Ideally we'd just have a way to perform a final check on the file into which a ref name was resolved to see its "real" name but I don't know whether all popular filesystems are case preserving (HFS+ and NTFS are, IIRC) and even if they are, whether the appropriate platform-specific APIs exists to perform such a check.