swain-sync

name	swain-sync
description	Fetch upstream, rebase, stage all changes, run ADR compliance check on modified artifacts, generate a descriptive commit message from the diff, commit, and push to the current branch's upstream. Handles merge conflicts by preferring local changes for config/project files and upstream for scaffolding.
user-invocable	true
allowed-tools	Bash, Read, Edit
metadata	{"short-description":"Fetch, stage, commit, and push","version":"1.3.0","author":"cristos","license":"MIT","source":"swain"}

Run through the following steps in order without pausing for confirmation unless a decision point is explicitly marked as requiring one.

Delegate this to a sub-agent so the main conversation thread stays clean. Include the full text of these instructions in the agent prompt, since sub-agents cannot read skill files directly.

Step 1 — Detect worktree context and fetch/rebase upstream

First, detect whether you are running in a git linked worktree:

GIT_COMMON=$(git rev-parse --git-common-dir)
GIT_DIR=$(git rev-parse --git-dir)
IN_WORKTREE=$( [ "$GIT_COMMON" != "$GIT_DIR" ] && echo "yes" || echo "no" )
REPO_ROOT=$(git rev-parse --show-toplevel)

IN_WORKTREE=yes means the current directory is inside a linked worktree (e.g., .claude/worktrees/agent-abc123). Use this flag in Steps 3, 6, and the session bookmark step.

Next, check whether the current branch has an upstream tracking branch:

git --no-pager rev-parse --abbrev-ref --symbolic-full-name @{u} 2>/dev/null

If there is an upstream, fetch and rebase to incorporate upstream changes BEFORE staging or committing:

git fetch origin

If there are local changes (dirty working tree), stash them first:

BRANCH=$(git rev-parse --abbrev-ref HEAD)
git stash push -m "swain-sync: auto-stash [$BRANCH]"
git --no-pager rebase origin/$BRANCH
git stash pop

If the rebase has conflicts after stash pop, abort and report:

git rebase --abort  # if rebase itself conflicts
git stash pop       # recover stashed changes

Show the user the conflicting files and stop. Do not force-push or drop changes.

If there is no upstream (@{u} returns an error) and IN_WORKTREE=yes, the worktree branch has no remote tracking counterpart. Rebase onto origin/main so the commits apply cleanly as a fast-forward:

git fetch origin
git rebase origin/main

If origin cannot be fetched, skip fetch/rebase and proceed to Step 2.

If there is no upstream and IN_WORKTREE=no (main worktree, new branch), skip this step entirely.

Step 2 — Survey the working tree

git --no-pager status
git --no-pager diff          # unstaged changes
git --no-pager diff --cached # already-staged changes

If the working tree is completely clean and there is nothing to push, report that and stop.

Step 3 — Stage changes

Identify files that look like secrets (.env, *.pem, *_rsa, credentials.*, secrets.*). If any are present, warn the user and exclude them from staging.

If there are 10 or fewer changed files (excluding secrets), stage them individually:

git add file1 file2 ...

If there are more than 10 changed files, stage everything and then unstage secrets:

git add -A
git reset HEAD -- <secret-file-1> <secret-file-2> ...

Step 3.5 — Gitignore check

Before committing, verify .gitignore hygiene. This step is advisory — it warns but never blocks the commit.

1. Check existence: If no .gitignore file exists in the repo root, warn:

   WARN: No .gitignore file found. Consider creating one to avoid tracking build artifacts, secrets, and OS files.

2. Check common patterns: If .gitignore exists, check whether these commonly ignored patterns are present (exact match or substring):

   • .env
   • node_modules/
   • __pycache__/
   • .DS_Store
   • *.pyc

   For each missing pattern, collect it. If any are missing, warn:

   WARN: .gitignore is missing common patterns: .env, node_modules/. Consider adding them.

   If all patterns are present (or none are relevant to the repo), this step is silent.

3. Continue to Step 4 regardless of warnings.

Step 3.7 — ADR compliance check

If modified files include any swain artifacts (docs/spec/, docs/epic/, docs/vision/, docs/research/, docs/journey/, docs/persona/, docs/runbook/, docs/design/), run an ADR compliance check against each modified artifact:

bash skills/swain-design/scripts/adr-check.sh <artifact-path>

For each artifact with findings (exit code 1 — DEAD_REF or STALE), collect the output and present a single consolidated warning after all checks complete:

ADR compliance: N artifact(s) have findings that may need attention.

This step is advisory — it warns but never blocks the commit. Continue to Step 4 regardless.

If the adr-check.sh script is not found or fails with exit code 2, skip silently — the check is only available in repos with swain-design installed.

Step 4 — Generate a commit message

Read the staged diff (git --no-pager diff --cached) and write a commit message that:

• Opens with a conventional-commit prefix matching the dominant change type:
  • feat — new feature or capability
  • fix — bug fix
  • docs — documentation only
  • chore — tooling, deps, config with no behavior change
  • refactor — restructuring without behavior change
  • test — test additions or fixes
• Includes a concise imperative-mood subject line (≤ 72 chars).
• Adds a short body (2–5 lines) summarising why, not just what, when the diff is non-trivial.
• Appends a Co-Authored-By trailer identifying the model that generated the commit. Use the model name from your system prompt (e.g., Claude Opus 4.6, Gemini 2.5 Pro). If you can't determine the model name, use AI Assistant as a fallback.

Example shape:

feat(terraform): add Cloudflare DNS module for hub provisioning

Operators can now point DNS at Cloudflare without migrating their zone.
Module is activated by dns_provider=cloudflare and requires only
CLOUDFLARE_API_TOKEN — no other provider credentials are validated.

Co-Authored-By: Claude Opus 4.6 <[e-mail]>

Step 4.5 — Pre-commit hook check

Check if pre-commit hooks are configured:

test -f .pre-commit-config.yaml && command -v pre-commit >/dev/null 2>&1 && echo "hooks-configured" || echo "no-hooks"

If no-hooks, emit a one-time warning (do not repeat if the same session already warned):

WARN: No pre-commit hooks configured. Run /swain-init to set up security scanning.

Continue to Step 5 regardless — hooks are recommended but not required.

Step 5 — Commit

git --no-pager commit -m "$(cat <<'EOF'
<generated message here>
EOF
)"

Use a heredoc so multi-line messages survive the shell without escaping issues.

IMPORTANT: Never use --no-verify. If pre-commit hooks are installed, they MUST run. There is no bypass.

If the commit fails because a pre-commit hook rejected it:

1. Parse the output to identify which hook(s) failed and what was found
2. Present findings clearly:

   Pre-commit hook failed: gitleaks: 2 findings (describe what was flagged)

   Fix the findings and run /swain-sync again. Suppress false positives: add to .gitleaksignore

3. Stop execution — do not push. Do not retry automatically.

Step 6 — Push

If IN_WORKTREE=yes: push the worktree's commits directly to main rather than creating a remote worktree branch:

git push origin HEAD:main

If this push is rejected with a non-fast-forward error:

• Check whether the rejection message mentions branch protection rules or required reviews.
  • If branch protection is the cause, open a PR instead:

    BRANCH=$(git rev-parse --abbrev-ref HEAD)
    SUBJECT=$(git log -1 --pretty=format:'%s')
    BODY=$(git log -1 --pretty=format:'%b')
    gh pr create --base main --head "$BRANCH" --title "$SUBJECT" --body "$BODY"
    

    Report the PR URL. Do not retry the push. Proceed to worktree pruning below.
  • If diverged history is the cause (not branch protection), report the conflict and stop. Do not force-push.

After a successful push or PR creation, remove the worktree:

WORKTREE_PATH=$(git worktree list --porcelain | grep -B2 "HEAD" | awk '/worktree/{print $2}' | grep -v "$(git rev-parse --git-common-dir | sed 's|/.git$||')")
git -C "$(git rev-parse --show-toplevel 2>/dev/null || git rev-parse --git-common-dir | sed 's|/.git||')" worktree remove --force "$WORKTREE_PATH" 2>/dev/null || true
git -C "$(git rev-parse --git-common-dir | sed 's|/.git||')" worktree prune 2>/dev/null || true

If IN_WORKTREE=no (main worktree, normal case):

git push          # or: git push -u origin HEAD (if no upstream)

If push fails due to divergent history (shouldn't happen after Step 1 rebase, but as a safety net):

git --no-pager pull --rebase
git push

Step 7 — Verify

Run git --no-pager status and git --no-pager log --oneline -3 to verify the push landed and show the user the final state. Do not prompt for confirmation — just report the result.

Index rebuild (SPEC-047)

Before committing (after staging, before Step 5), check whether any artifact index files (list-*.md) are stale. If skills/swain-design/scripts/rebuild-index.sh exists, run it for each artifact type that had changes staged:

REBUILD_SCRIPT="$REPO_ROOT/skills/swain-design/scripts/rebuild-index.sh"
if [[ -x "$REBUILD_SCRIPT" ]]; then
    # Detect which types had staged changes
    for type in spec epic spike adr persona runbook design vision journey; do
        if git diff --cached --name-only | grep -q "^docs/$type/"; then
            bash "$REBUILD_SCRIPT" "$type"
            git add "docs/$type/list-${type}.md" 2>/dev/null || true
        fi
    done
fi

This ensures the index is current when the session's commits land.

Session bookmark

After a successful push, update the bookmark. Use $REPO_ROOT (set in Step 1) as the search root so this works from both main and linked worktrees:

bash "$(find "$REPO_ROOT" -path '*/swain-session/scripts/swain-bookmark.sh' -print -quit 2>/dev/null)" "Pushed {n} commits to {branch}"