Subject: git push vs. slow connection times - local commit resolution is too late

From: Eric Blake <[email-masked]>
Date: Thu, 14 Jul 2011 07:22:50 -0600

I've been bitten several times by this bug now, so I'll report it in the
hopes that someone knows what to do to patch it.

Scenario - I have a remote repository that takes on the order of 10
seconds to connect to, for any operation like 'git push'.  I know that
there is a lag, so I intentionally have two terminals open, both
visiting the same directory, one for interaction with the remote, and
the other for acting on the local repository, with the hope that I can
do useful work in the second terminal rather than idly waiting on the
lag in the first terminal.

In the middle of rebasing a patch series, where I want to incrementally
push the patches that I have gotten through so far, I used the following
steps:

On the remote-interaction terminal, I push the current state of my tree:
git push remote HEAD:master

On the local-interaction terminal, I move on to the next patch:
git rebase --continue

then, to my horror, I find out that the commit I'm working on locally
has already been pushed!  Why?  Because 'git push remote HEAD:master'
does not determine which commit 'HEAD' refers to until _after_ it has
established a connection to remote, but the stupid 10-second lag was
long enough that my actions in my second terminal have changed HEAD in
the meantime.

I would really love it if 'git push' would resolve all local references
_prior_ to trying to connect to the remote server, rather than waiting
until after the connection.  That way, my remote-interaction terminal
can truly be a type-it-and-forget-it terminal, where the push action I
requested reflects the state of the tree at the time I requested it,
rather than picking up changes made later in another terminal.

-- 
Eric Blake   [email-masked]    +1-801-349-2682
Libvirt virtualization library http://libvirt.org