rollback

name	rollback
description	Use when the user asks to roll back or undo work from a CLoClo pipeline run (/rollback, 'undo pipeline', annule, reviens en arriere).

/rollback — Undo Pipeline Work

Safely undo commits made by the CLoClo pipeline. Two modes: soft (uncommit, keep the files as staged changes) and hard (also discard the file changes). This skill only touches pipeline commits and never force-pushes; read the whole flow before acting.

Step 0: Sanity checks (fail gracefully)

# Are we in a git repo at all?
git rev-parse --git-dir >/dev/null 2>&1 || { echo "NOT_A_REPO"; exit 0; }

# Detached HEAD? Rolling back is ambiguous — bail with a clear message.
git symbolic-ref -q HEAD >/dev/null || echo "DETACHED_HEAD"

# How many commits does history actually have? (avoids HEAD~N errors on short history)
DEPTH=$(git rev-list --count HEAD 2>/dev/null || echo 0)
echo "DEPTH=$DEPTH"

Handle each case explicitly, then stop:

• NOT_A_REPO → Pas de dépôt git ici — rien à annuler.
• DETACHED_HEAD → HEAD est détaché (pas sur une branche). Checkout une branche avant de rollback.
• DEPTH=0 → Aucun commit dans l'historique — rien à annuler.
• If a requested range would exceed DEPTH (e.g. reset HEAD~10 in a 3-commit repo), clamp to the repo root or refuse with Seulement {DEPTH} commit(s) dans l'historique.

Step 1: Identify the pipeline commits

The only reliable pipeline-commit boundary is base_ref..HEAD from the latest session's checkpoint.json (Phase 5 execution commits carry no marker). Find the latest session by mtime and read the boundary from it.

SESSION_DIR=$(ls -dt docs/cloclo-sessions/*/ 2>/dev/null | head -1)
CHECKPOINT="$SESSION_DIR/checkpoint.json"
if [ -n "$SESSION_DIR" ] && [ -f "$CHECKPOINT" ]; then
  BASE_REF=$(jq -r '.artifacts.base_ref // empty' "$CHECKPOINT")
  # Pipeline-created commits (either key may be present):
  jq -r '(.artifacts.commit_list // .artifacts.commits // [])[]' "$CHECKPOINT"
  echo "BASE_REF=$BASE_REF"
fi

If a checkpoint with base_ref exists → default the rollback range to ${BASE_REF}..HEAD:

git log --oneline "${BASE_REF}..HEAD"

Then diff the range against the recorded commit_list and flag interlopers — any commit in the range that the pipeline did NOT create (a user commit interleaved with pipeline work):

# For each SHA in ${BASE_REF}..HEAD, check membership in commit_list.
git rev-list "${BASE_REF}..HEAD"

For every SHA in the range that is absent from commit_list, tell the user: Ce commit ne vient pas du pipeline : <sha> "<subject>" — l'exclure du rollback ? Default to excluding non-pipeline commits.

If no checkpoint / no base_ref exists → fall back to the manual numbered list:

git log --oneline -10

Recent commits:
  1. a1b2c3d feat: add upload component (3 min ago)
  2. d4e5f6g feat: add upload tests (5 min ago)
  3. h7i8j9k refactor: extract form hook (8 min ago)
  4. k0l1m2n chore: update deps (yesterday) ← probably not from this pipeline

If the session produced zero commits (empty commit_list / base_ref == HEAD) → Cette session n'a créé aucun commit — rien à annuler. and stop.

Step 2: Safety checks

git status --porcelain

If the tree is not clean, be precise about what each mode does — do NOT claim work is always preserved:

Tu as des changements non commités.
- Soft rollback : ils sont conservés (le reset --soft ne touche pas le working tree).
- Hard rollback : ils seraient DÉTRUITS. Je refuse tant que l'arbre n'est pas propre,
  ou je les mets de côté avec `git stash push -u` d'abord (je te le dis explicitement).

Detect commits that are already pushed — compare against the current branch's upstream, NOT the remote default branch:

git rev-parse --abbrev-ref --symbolic-full-name @{u} >/dev/null 2>&1 \
  && git log --oneline @{u}..HEAD 2>/dev/null | wc -l \
  || echo "NO_UPSTREAM"

• NO_UPSTREAM → no upstream configured: treat all commits as local (safe to reset).
• Otherwise, commits NOT in @{u}..HEAD are already pushed. Never reset --hard a pushed commit (unrecoverable given the NEVER-force-push rule) — revert it instead:

ATTENTION : {N} de ces commits sont déjà poussés (upstream).
Soft rollback : sans risque (local). Pour les commits poussés, hard = `git revert` (nouveaux
commits d'annulation), jamais `reset --hard`. Ne force-push jamais.

Step 3: Ask what to undo

The default selection is the flagged pipeline range from Step 1.

Que veux-tu annuler ?

A. Dernier commit du pipeline seulement
B. Toute la plage du pipeline (base_ref..HEAD)
C. Les N derniers commits (tu précises N, borné à la plage pipeline)
D. Annuler — ne rien faire

Step 4: Choose rollback type

Always show the exact file impact of the chosen range BEFORE asking (soft and hard both):

git diff --stat "${BASE_REF}..HEAD"   # or the selected sub-range

Comment annuler ?

Soft — Décommit, mais garde les fichiers modifiés (staged)
  → git reset --soft <range-base>
  → Tu peux ré-éditer et re-committer.
  → Note : des changements staged peuvent bloquer la reprise (garde-fou arbre-propre
    de la Phase 9). Committe ou stash avant de relancer /pipeline.

Hard — Revenir complètement en arrière (fichiers inclus)
  → commits LOCAUX : git reset --hard <range-base> (arbre propre requis)
  → commits POUSSÉS ou merge/squash : git revert (voir Step 5)

Choix ? (soft/hard)

Step 5: Execute

Use an explicit base SHA (${BASE_REF} or the selected commit's parent) rather than a bare HEAD~{N} so short/interleaved history can't miscount.

Soft rollback:

git reset --soft "$BASE_REF"

Print: Commits décommittés. Les fichiers restent modifiés (staged). Tu peux ré-éditer.

Hard rollback — local commits, clean tree only:

# Gate: refuse or stash first if the tree is dirty.
if [ -n "$(git status --porcelain)" ]; then
  git stash push -u -m "rollback-safety $(date +%F-%T)"   # only after telling the user
fi
git reset --hard "$BASE_REF"

Print: Commits annulés, fichiers revenus à l'état précédent. (If you stashed, add: Tes changements non commités sont dans git stash (stash@{0}).)

Hard rollback — pushed commits, or any merge/squash commit:

# Plain revert of a linear range fails on merge commits; use -m 1 for those.
# Phase 9 squash-merge case: undo ONE squash SHA recorded in the checkpoint.
git revert -m 1 <squash_or_merge_sha> --no-edit     # merge/squash commit
git revert "${BASE_REF}..HEAD" --no-edit            # linear, non-merge range

Detect merge/squash commits first (git rev-list --merges "${BASE_REF}..HEAD", or the squash_sha recorded in the checkpoint after Phase 9 merged to main) and route them through git revert -m 1 <sha>. Print: Commits revertés via nouveaux commits d'annulation. Push quand tu es prêt.

Post-auto-merge scenario: after Phase 9 squash-merges to main, the whole run is a single squash commit (its SHA is in the checkpoint). Undoing it is one git revert -m 1 <squash_sha> — not a multi-commit range.

Step 6: Update pipeline state

Locate the session the same way as Step 1: the most recent directory by mtime under docs/cloclo-sessions/ — its checkpoint.json holds the phase state.

If that checkpoint.json exists:

1. Read it.
2. Set last_completed_phase to the phase BEFORE the rolled-back work.
3. Write the updated checkpoint.
4. Print: Checkpoint mis à jour — /pipeline reprendra à Phase {N}.

If a handoff.md exists, append:

## Rollback: {date}
- Rolled back {N} commits ({soft|hard})
- Pipeline checkpoint reset to Phase {M}

Rules

• NEVER force-push. Use git revert (with -m 1 for merge/squash commits) for anything already pushed — a reset --hard on pushed commits is unrecoverable under this rule.
• NEVER reset --hard on a dirty tree. Require a clean tree, or git stash push -u first and say so; state precisely what each mode preserves (soft keeps the working tree, hard discards it).
• ALWAYS show exactly which files will change — git diff --stat <range> in the confirmation for both soft and hard.
• Only roll back pipeline commits. Default to base_ref..HEAD from the latest checkpoint and flag any non-pipeline commit in the range for exclusion.
• Fail gracefully on no-repo, detached HEAD, short/empty history, and zero-commit sessions.
• Update checkpoint. The pipeline must know where to resume after rollback.