Advance Main, Advance Subrepo

export only ever moves a subrepo’s subrepo branch - it never touches main, so main falls one commit behind after every export. Two commands catch it back up, at different scopes:

• central advance-main <repo> fast-forwards that subrepo’s local main branch to match subrepo, from the same machine an export (or import) just ran on - the everyday, single-machine case.
• central advance-subrepo <repo> is the more thorough version, aimed at a second machine: after pulling central’s own main (which brings in whatever .gitrepo now says), it fast-forwards that subrepo’s local subrepo and main branches to match - both in one go, provided the commit .gitrepo points to is already present locally (e.g. already fetched from the subrepo’s real remote - advance-subrepo itself never fetches anything).

Advance-main, right after an export

export lands a commit on widget’s subrepo branch - main hasn’t moved:

$ central advance-main widget
==================== widget ====================
Updating 1185512..f452a6f
Fast-forward
 README.md | 2 ++
 1 file changed, 2 insertions(+)

main is fast-forwarded to the same commit subrepo already carried:

Document installation
Initial commit

Right after Central_test_helpers.create, there’s nothing for main to catch up to:

$ central advance-main widget
==================== widget ====================
[SKIP] Skipping [advance-main] (not applicable).

Advance-subrepo, catching up a fresh checkout on another machine

Say a change was already exported and pushed from elsewhere: central’s own .gitrepo (as pulled from its real remote) now points at a newer widget commit, already fetched into this machine’s own checkout of widget (e.g. by a plain git fetch, run once ahead of time), but not yet merged into either its subrepo or main branch. advance-subrepo brings both up to date in one command:

$ central advance-subrepo widget
==================== widget ====================
Updating f452a6f..1185512
Fast-forward
 README.md | 2 ++
 1 file changed, 2 insertions(+)
Updating f452a6f..1185512
Fast-forward
 README.md | 2 ++
 1 file changed, 2 insertions(+)

subrepo is on the new commit now:

Document installation
Initial commit

And so is main - both branches now point at the very same commit:

Document installation
Initial commit