Hey Sarah,
First of all: awesome, thank you for taking interest in helping out your fellow openstack'er by taking a change over the line.
There are two answers to this, really, technical and etiquette:
- From a technical perspective, you can download an existing change with `git review -d ######` (with the patch number) to download it, add changes, and roll those changes into the original commit using `git commit --amend` or by making a new commit and rebasing it into the original one.
- From an etiquette perspective[0], I try to get permission from folks before editing their patches, with a few exceptions -- for instance, for a community member I'm familiar with (and know they likely wouldn't mind), if there's a small change needed to allow it to merge, I'll often make that minor change -- especially if I know there are other cores online to help immediately land it. If the original contributor is gone and/or out of communication, that's another case where I would be willing to take over a patch without asking.
As far as formal requirements, under our new DCO (Signed-off-by:) requirements, anyone who additionally makes a change to a patch must add their sign-off as well, attesting that the code they added is A-OK for OpenStack use.
-JayF
0: I am talking generally based on my experiences with Ironic. I suspect the norms are slightly different for each project, so maybe someone kolla-oriented will chime in :).