Per https://wikitech.wikimedia.org/wiki/Incidents/2023-05-30_Unintentional_%2B2_on_a_config_patch_without_deployment, there was a suggestion on the meeting whether to (if not already available), warn against the deployment of a config patch if not specified by the scap backport ... command.
So assuming that a deployer is in the process of deploying a patch or patches and there is a patch that was recently merged or merged and forgotten to be deployed (but shows up as part of the diff), scap should detect that and warn the deployer about it.
Let's assume a patch: abc that was recently merged not to be deployed immediately (in a deploy window) or merged and forgotten, and a deployer wants to deploy several config patches: xyz, ijk, then runs the command: scap backport xyz ijki. Scap should detect that abc is part of the diff but not specified explicitly to be deployed and warn the deployer about it.
This way, the deployer can make a revert of the patch (abc) or ping the author whether they're around to deploy the change or not (schedule for another window).
Resolution
scap backport does have a check for this situation. If an unexpected commit is fetched during a backport, scap backport will generate output like the following:
19:14:06 The following are unexpected commits pulled from origin for /srv/mediawiki-staging:
commit c5e2ce837b52418164db3d24346127f5ca127c05 (origin/train-dev)
Author: Train Conductor <tconductor@wikimedia.org>
Date: Thu Jun 29 19:13:07 2023 +0000
setup_config_change(backport_with_extra_commits)
Change-Id: I8ec0ac3409e5ecc12f4a66253627a32ae41703ea
Would you like to see the diff? (y/n): y
commit c5e2ce837b52418164db3d24346127f5ca127c05 (origin/train-dev)
Author: Train Conductor <tconductor@wikimedia.org>
Date: Thu Jun 29 19:13:07 2023 +0000
setup_config_change(backport_with_extra_commits)
Change-Id: I8ec0ac3409e5ecc12f4a66253627a32ae41703ea
diff --git a/README b/README
index 843875375..673796b95 100644
--- a/README
+++ b/README
@@ -237,3 +237,5 @@ Added by setup_config_change(already_merged, backport_with_extra_commits) on 202
Added by setup_config_change(normal, test_config_changes(normal)) on 2023-06-29 19:07:21
Added by setup_config_change(already_merged, test_config_changes(already_merged)) on 2023-06-29 19:08:13
+
+Added by setup_config_change(already_merged, backport_with_extra_commits) on 2023-06-29 19:13:07
19:14:06 There were unexpected commits pulled from origin for /srv/mediawiki-staging.
Continue with backport? (y/n):