Review feedback on #89507: in-place merging suits a branch that tracks the
target with a small patch set, but a long-lived feature branch (a PR branch
hundreds of commits deep) does not want an update-driven merge commit
written into its history. Reported against a checkout carrying 819 unmerged
commits.
--switch-branch routes the unmerged case to the switch path instead: the
checkout moves to the update target and updates there, and the branch is
left byte-identical — no merge, no commit, nothing written to it. The tree
is known clean on that path (the guard checks dirty before cherry), so a
dirty tree still gets the loud skip, unchanged.
Opt-in: without the flag the default remains the in-place update, which is
what keeps a small-patch-set branch's running code current.
Tests: the flag switches and leaves the branch tip byte-identical; the
default without it still updates in place. The first fails if the flag's
branch is severed.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The parked-branch guard (8ce8ffd429) distinguishes checkouts by what the
branch carries, then treats both non-clean cases the same: a stale
fully-merged leftover is switched back to the target (correct), but a
branch with unmerged commits — a branch someone is actually working on —
gets CODE UPDATE SKIPPED and exit 1. For anyone running a maintained
custom branch on top of main, every update now refuses, and the guidance
('checkout main') abandons their branch.
The guard's own reason codes already separate the cases, so use them:
- fully merged -> switch back to the target (unchanged)
- unmerged:N -> update the branch IN PLACE: fetch, then bring
origin/<target> into the checkout. Fast-forward
when possible; on divergence, a true merge behind
a pre-update safety tag, stopping cleanly on
conflict. The checkout never moves; local commits
survive; the running code advances.
- dirty/unverifiable/opted out -> skip loudly (unchanged)
The post-pull success gate learns that an in-place update legitimately
ends on a non-target branch: origin/<target> was merged INTO the checkout,
so refusing to claim success there would fail every update that did
exactly the right thing.
Guard tests updated: the unmerged case now asserts the in-place outcome —
target code arrives (b.txt from c3), the branch's own commit survives, and
HEAD never moves. 18/18 guard tests, 20/20 with the diverged-update suite.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
A clean checkout parked on a feature branch now always switches to the
update target. Unmerged commits are safe on the branch (git checkout
never discards committed work) and get a loud 'kept' notice naming the
branch, count, and the checkout command to resume the work. Previously
the update hard-skipped with exit 1 — a dead end for the desktop update
button, gateway /update, and cron, which have no way to resolve a skip.
Dirty trees (uncommitted changes) still skip loudly, and the
updates.auto_switch_parked_branch: false opt-out still pins the branch.
Live incident 2026-08-17: the source checkout was parked on a stale feature
branch (claude-code-inspired/local-terminal-memory-limit, days behind main),
left there by earlier tooling. 'hermes update' autostashed, refreshed lazy
backends, synced skills, and printed '✓ Code updated!' / '✓ Update complete!'
while the checkout stayed on the stale branch with none of main's new code.
Two sessions burned time on 'the fix is missing' confusion.
- Parked-branch guard: auto-switch back to the update target ONLY when the
parked branch is clean and fully merged (git cherry origin/<target> shows
nothing unmerged); the checkout then STAYS on the target instead of being
re-parked. Otherwise: loud CODE UPDATE SKIPPED block naming the branch,
behind-count, and resolution commands; exit 1; branch untouched.
- The up-to-date (commit_count == 0) path no longer switches back to a
fully-merged parked branch either.
- Post-pull gate additionally refuses to print '✓ Code updated!' when HEAD
ends up attached to a non-target branch.
- Summary lines now carry the actual branch + HEAD short-sha:
'✓ Update complete! [main @ 30fcf9580]' — drift visible at a glance.
- New config toggle updates.auto_switch_parked_branch (default true).
- Real-git-fixture regression tests (init/clone/branch, no subprocess
mocks): clean+merged auto-switch, dirty skip, unmerged skip, cherry-picked
equivalence, config opt-out, unverifiable ref, on-main fast path,
up-to-date no-repark, summary branch/sha assertions.
Willian Santos