Re: [PATCH v2 1/4] t1400: Avoid touching refs on filesystem

[Junio C Hamano <gitster@pobox.com>]

Patrick Steinhardt <ps@pks.im> writes:

>> For now, I think this is fine, but we'd probably clean it up so that
>> without --force update-ref would not corrupt the repository like
>> this.  When used with --force, or before adding such a safety
>> measure, how we test if we successfully corrupted the repository is
>> an interesting matter.  I'd say
>> 
>> 	git update-ref --force --no-deref -d HEAD &&
>> 	test_must_fail git show-ref --verify -q HEAD &&
>> 	cp -f .git/HEAD.orig .git/HEAD &&
>> 	git show-ref --verify -q "$m"
>> 
>> to ensure that other than removing HEAD and corrupting the
>> repository, it did not cause permanent damage by removing the
>> underlying ref, perhaps.
>> 
>> We may want to add some NEEDSWORK comment around such tests.
>
> I think the proper way to do the test would be to create a non-mandatory
> symref and delete it. That'd also be a nice preparation for the
> `--force` parameter already.

Excellent.  Yes, the test is about creation and removal of a symref;
the symref used for testing does not have to be the HEAD.

Thanks.