Re: question concerning branches

From: Junio C Hamano <gitster@pobox.com>
Date: Aug 19, 2009, 18:35 UTC
Message-ID: <7vr5v7vehj.fsf@alter.siamese.dyndns.org>
In-Reply-To: <4a8c373f@wupperonline.de>

ib@wupperonline.de (Ingo Brueckl) writes:

Show 11 quoted lines

> I'm a git novice and have a comprehension question concerning branches.
>
> Within a git repository, I do:
>
>   git branch test
>   git checkout test
>   # edit foo.bar
>   git checkout master
>
> I'd expect that master is in the exactly same unchanged state it was at
> branching time, but what a surprise, foo.bar is modified here, too!

No. Local modification that are not committed do not belong to any branch. Rather it belongs to your work tree and the index, and follow you when you switch branches.

This is one of the most useful features. For example, it is an essential part of supporting the workflow described here:

    http://gitster.livejournal.com/25892.html

On the other hand, there are cases that you do not want to see your local changes to foo.bar appear when you switch back to master, and the most obvious case is "I started working on something, and I used a separate branch 'test' because the change will be involved. I am in the middle of the work, the changes so far I made to foo.bar is far from ready, but I have to handle emergency fix on the master branch". For that kind of situation, you can use "git stash", like:

    http://gitster.livejournal.com/29577.html