Re: [PATCH] t1402: test forbidden characters in refnames

On Thu, Aug 13, 2026 at 08:43:56PM +0000, Nikolaus Schuetz via GitGitGadget wrote:

From: Nikolaus Schuetz <redacted>

git-check-ref-format(1) documents that a refname cannot contain a
space, tilde, caret, colon, question-mark, asterisk or open-bracket,
and that it cannot be the single character "@".  Of these, only "?"
was tested as a character embedded in an otherwise-valid refname;
"*" was checked only as a lone character or with --refspec-pattern.

Add the remaining forbidden characters in that embedded form, and
check that "@" alone is rejected even with --allow-onelevel -- where
"@" is otherwise a valid refname component, as "refs/@" confirms.

Okay.

This feels a tiny bit excessive, but I guess it does not hurt to enforce
this property, especially now that it's so easy to add new backends.

One thing I was briefly wondering is whether we could maybe have a
simple loop here, as this feels quite repetitive. We could for example:

    for c in '?' '~' '^' ':' '*' '[' ' '
    do
        invalid_ref "heads/foo${c}bar"
    done

By the way, one weird bit: is it intentional that all of these really
use "heads/something" instead of "refs/heads/something"? I guess it
ultimately doesn't matter.

 valid_ref 'foo./bar'
 invalid_ref 'heads/foo.lock'
 invalid_ref 'heads///foo.lock'
 invalid_ref 'foo.lock/bar'
 invalid_ref 'foo.lock///bar'
 valid_ref 'heads/foo@bar'
+valid_ref 'refs/@'
+invalid_ref '@' --allow-onelevel

This one certainly is a good addition, as these are quite a bit more
subtle.

Thanks!

Patrick