A pair of integration tests against a real sshd-based "upstream"
sibling container that prove every operation through the gate is
observably equivalent to the same operation against the upstream:
- test_clone_and_refetch_reflect_upstream: clone via gate
returns the upstream's current commit; an out-of-band commit
on the upstream shows up via the gate on the next ls-remote.
- test_push_through_gate_lands_on_upstream: a clean push routed
through the gate lands on the upstream's bare repo.
The upstream container is a tiny inline-built alpine image with
openssh-server, a `git` user (passwd -u so sshd doesn't reject
the locked account), and a baked bare repo seeded with one
commit. Host keys are baked in at build so the test can pin
KnownHostKey on the manifest entry before the container starts.
While wiring this up the access-hook gained a one-shot HEAD
sync: `git init --bare` defaults HEAD to refs/heads/master, and
upstreams that use main would leave the bare repo's HEAD
unresolvable — clones came through but the working tree was
empty. The hook now does a `rev-parse --verify HEAD` check
after the first fetch and runs `ls-remote --symref` to repoint
HEAD if it doesn't resolve. One extra round-trip on first
fetch only.
didericis
f9d9e9cf33