Aircall Merge Train

aircall-merge-train (stage 4 of the react-doctor pipeline, but reusable for any MR batch)

Merges a batch of MRs that are already approved and Ready, one at a time, on a repo using fast-forward merge (merge_method=ff). This is a supervised main-loop, NOT a Workflow script: it spans hours (CI-paced) and stops for human decisions. Pace it with ScheduleWakeup (~120s) per the /loop pattern; report progress to the user (and Slack if asked).

Why this is a loop, not a workflow

ff + reset_approvals_on_push + Bugbot gates + day-long approval latency mean a deterministic background script can't sit and wait or make the judgment calls. Keep it in the main loop where it can DM/ask the user.

Inputs

• A list of MR iids to merge (e.g. aircall-react-doctor-pipeline's readyMRs), or "all open approved MRs matching a branch prefix". (Nothing here is react-doctor-specific — any approved MR batch works.)
• Project (path-encoded for glab api, e.g. aircall%2Fdashboard-extensions%2Fconversation-center-ext).
• Optional Slack channel/thread for progress, and a DM channel for decisions.

Setup (once)

1. glab auth status — confirm authenticated.
2. Read repo merge settings: glab api projects/$ENC | jq '{merge_method, only_allow_merge_if_pipeline_succeeds, only_allow_merge_if_all_discussions_are_resolved, reset_approvals_on_push}'. Confirm ff.
3. Persist a state file (e.g. .omc/state/mr-merge-train.json): {queue, merged, skipped, blocked, needs_approval, current} so the loop survives compaction/restart.
4. Parsing note: MR descriptions often contain raw control chars that break jq. Parse glab api MR objects with python3 -c "import sys,json; d=json.loads(sys.stdin.read(),strict=False); ...".

Per-MR procedure (strictly one at a time)

For current MR:

1. Rebase: glab api -X PUT projects/$ENC/merge_requests/$mr/rebase; wait ~13s.
2. Re-check detailed_merge_status (dms):
   • need_rebase (raced — another MR merged) → rebase again.
   • not_approved → the rebase changed the diff and reset_approvals_on_push cleared approval. Do NOT arm. Move to needs_approval, re-queue at END, advance. (Ping the approver if the user wants.)
   • discussions_not_resolved → a Cursor Bugbot thread (author project_*_bot_*) is blocking. Read it; do not silently resolve High/Medium findings. Cancel auto-merge (POST .../cancel_merge_when_pipeline_succeeds), move to blocked, DM the user with the finding, advance.
   • mergeable / ci_still_running → proceed.
3. Conflict on rebase (merge_error: "Rebase failed"):
   • If it's doctor.config.json (or any file the user pre-flagged) → do NOT skip; DM the user and wait for instructions.
   • Otherwise → skipped + note "needs local rebase", advance. (Optionally spawn a worktree agent to resolve.)
4. Arm auto-merge: glab api -X PUT projects/$ENC/merge_requests/$mr/merge -f merge_when_pipeline_succeeds=true. If the pipeline is already green it merges immediately.
5. Poll every ~120s (ScheduleWakeup): when state==merged → record, advance to next. If mwps dropped to false (fell behind main) → re-rebase + re-arm.
6. Flaky E2E: if the pipeline fails on a known-flaky job (e.g. e2e-509-admin-merge-branch Playwright timeout) unrelated to the diff → retry that job once (POST projects/$ENC/jobs/$jid/retry); leave mwps armed. If it fails again → skipped + note "needs attention".
7. Real CI failure (e.g. check-fallow, check-ts-compile) → inspect the job trace; skipped + note the cause. Do NOT push code changes to an approved MR autonomously unless the user said so.

Re-approval pile

Items in needs_approval need a human approval that may arrive much later. Each cycle, re-check their approval; when approved, move into the queue (they'll be rebased+armed when they become current). Note: re-arming requires a rebase, which may reset approval again if the diff changed — surface that.

Finish

When the queue is empty and only undecided items remain (blocked on Bugbot / unapproved / needing local fixes):

1. Stop rescheduling (do not call ScheduleWakeup).
2. Post a final summary (merged / skipped / blocked / needs-approval, with what each needs).
3. If a backlog/status doc exists, tick merged tickets and refresh the tally.
4. Clean up stale worktrees for merged/closed branches: verify each via glab MR state, then git worktree remove --force <wt> + git worktree prune. KEEP worktrees for open MRs and active WIP (no MR). Branch refs are preserved.

Hard-won gotchas (do not relearn)

• ff means every merge invalidates the others' rebase → strictly one at a time.
• reset_approvals_on_push fires on a rebase only when the rebase changes the MR's diff (overlap with siblings merged ahead). Clean replays keep approval.
• Never auto-resolve Bugbot High/Medium — that's a human call (DM).
• The shell here is zsh (the env may report fish): use for x in a b c; do …; done, not fish syntax; it does not word-split unquoted vars.
• Slack has no edit-message API exposed — post an updated checklist reply rather than editing.