Re: [PATCH] git-branch: show detached HEAD

From: Junio C Hamano <junkio@cox.net>
Date: Jan 3, 2007, 06:53 UTC
Message-ID: <7v7iw4r47e.fsf@assigned-by-dhcp.cox.net>
In-Reply-To: <20070103051811.GB23358@spearce.org>

"Shawn O. Pearce" <spearce@spearce.org> writes:

Show 6 quoted lines

> Lars Hjemli <hjemli@gmail.com> wrote:
>> This makes git-branch show a detached HEAD as '* (no branch)'.
>
> It would be nicer if when you are on a remote tracking branch or
> on a tag that the name of the tag or the remote tracking branch is
> shown rather than '* (no branch)'.

That would be utterly confusing if you are talking about the same detached HEAD semantics as I and Carl discussed today. I like what Lars's patch does (although I felt that it was too big for only doing this which made it harder to judge), but I would even make it stronger to say something like:

	* You are not on ANY branch right now.
          master
          next
          pu
          ...

You will never be _on_ a remote tracking branch. So far we did not allow HEAD to point at outside refs/heads/ and we still don't. When HEAD is detached from any branch, however, it can store a bare 40-hex (plus LF) commit object name instead of being a symref. You are not on any branch at that point.

Most importantly, if we allow commits to be built on top of HEAD while it is detached from any branch, the commit will _not_ advance any branch. So showing the remote tracking branch the way you suggest will be misleading.

If we do not allow commits to be built on top, we would still allow something to be done other than switching out of "detached mode" to be useful. For example, reset to move around which commit to look at would be a useful thing. Another of my unstated desire is to get rid of the use of special "bisect" branch during bisection using detached HEAD. Again, if we highlight remote tracking branch whose tip happens to be the same commit as the current HEAD as you suggest, that would lead to quite confusing behaviour. Sometimes it would say the same thing as you are _on_ that branch (which confuses you because you are _not_ on that branch in reality), sometimes it would highlight nothing to show you are not on any branch.