From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [issue?]'git branch -D' case sensitive issue
Date: Thu, 14 Jan 2016 09:21:46 -0800
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To: Torsten =?utf-8?Q?B=C3=B6gershausen?= <tboegi@web.de>
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In-Reply-To: <5697CFEB.4090308@web.de> ("Torsten =?utf-8?Q?B=C3=B6gershaus?=
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Torsten B=C3=B6gershausen <tboegi@web.de> writes:

> No, this is typically what we observe on a case insensitive FS.

There is an interesting bit in delete_branches::builtin/branch.c

	if (kinds =3D=3D FILTER_REFS_BRANCHES && !strcmp(head, bname.buf)) {
		error(_("Cannot delete the branch '%s' "
		      "which you are currently on."), bname.buf);
		ret =3D 1;
		continue;
	}

The strcmp() does not protect you from attempting to remove "FrOtZ"
branch when you are on (and more importantly, Git thinks you are on)
"frotz" branch.  A case-insensitive system then can tell Git that
the request to remove "refs/heads/FrOtZ" succeeded, even though in
reality it didn't have such file, and silently "refs/heads/frotz"
gets removed instead.  You can end up removing your current branch
that way.