[Insight-developers] Fwd: fix backport into 3.20, 3.21?

[Brad King]

On 09/23/2010 07:45 AM, Alexandre GOUAILLARD wrote:
> just a few questions regarding the releases.

I've been meaning to update the Wiki for this but haven't found time yet.

> My understanding is that the Release branch right now correspond to
> itk 3.21 and is where we should commit (critical) bug fixes for 3.20.
> Is it correct? Then those bugs are merged into master.

The 'release' branch is for 3.20 and will be used to produce 3.20.1,
3.20.2, etc. as necessary.  When 4.0 comes out the release branch will
fast forward to it and be used for 4.0.0, 4.0.1, etc.

> Everybody with write access to the repository would have write access
> to release branch as well.

Not quite.

Git allows everyone to start work from any commit in history.  Anyone
with write access or not can checkout the release tag and commit locally.
You can merge the fix to master (using the topic stage), and then ask
the gatekeeper (me) to merge it to the 'release' branch:

Starting point:

             o  release
            /
 v3.20.0-> o
          /
 ...o----o----o  master

You create bug fix from 3.20.0 (commit A):

             o  release
            /
 v3.20.0-> o-----A  my-bug-fix
          /
 ...o----o----o  master

You merge bug fix into master (commit B):

             o  release
            /
 v3.20.0-> o-----A
          /       \
 ...o----o----o----B master

I merge bug fix into release (commit C):

             o-----C  release
            /     /
 v3.20.0-> o-----A
          /       \
 ...o----o----o----B master


> what happen if a fix was commited first to master (like
> fd39d4138c579a3526511f21a12d3b03a611fa41)
> and then we realized it should also apply to another branch?

 $ git checkout -b my-bug-fix v3.20.0
 $ git cherry-pick fd39d41
 $ git push stage HEAD
 $ ssh git at itk.org stage ITK merge my-bug-fix

Then email me and ask for the topic to be merged to 'release' too.

-Brad