Rebase Current Branch on Latest Main

Fetch the latest default branch from origin and rebase the current branch on top of it, resolving conflicts as they appear. Do not push unless the user asks.

Step 1: Pre-Flight Checks

Before doing anything, verify the working tree state:

1. Run git status --porcelain=v1 --branch. Confirm there are no uncommitted changes. If there are:
   • List them to the user
   • Ask whether to stash (git stash push -u -m "rebase-skill autostash") or abort
   • Do NOT silently discard work
2. Run git rev-parse --abbrev-ref HEAD to capture the current branch name. If it is main, master, or the default branch, stop and tell the user there is nothing to rebase.
3. Determine the default branch:

   gh repo view --json defaultBranchRef --jq '.defaultBranchRef.name'

   Fall back to git symbolic-ref refs/remotes/origin/HEAD --short | sed 's@^origin/@@' if gh is unavailable. Cache the result as $BASE.
4. Confirm an origin remote exists with git remote get-url origin.

Step 2: Fetch the Latest Base

Fetch only what is needed and prune stale refs:

git fetch --prune origin "$BASE"

If the fetch fails (network/auth), report the exact error and stop. Do not start a rebase against stale refs.

Step 3: Start the Rebase

Run:

git rebase "origin/$BASE"

Capture both stdout and stderr. There are three outcomes:

Step 4: Resolve Conflicts (Loop)

Repeat this loop until git status reports the rebase is no longer in progress.

4a. Inventory the Conflicts

Run git status --porcelain=v1. Conflicted files are marked UU, AA, DU, UD, AU, UA, or DD.

For each conflicted file:

• Read the full file (do not rely on <<<<<<< markers alone for context)
• Identify the conflict regions delimited by <<<<<<<, =======, >>>>>>>
• Identify which side is "ours" (the rebased commit being replayed) and "theirs" (the base branch tip). During git rebase, "ours" is the upstream base and "theirs" is the commit being replayed — this is the opposite of git merge. Verify with git log --oneline -1 HEAD and git log --oneline -1 REBASE_HEAD if unsure.

4b. Resolve Each File

Apply this decision logic per conflict region:

After editing, ensure no <<<<<<<, =======, or >>>>>>> markers remain:

git grep -nE '^(<{7}|={7}|>{7})( |$)' -- ':(exclude)*.md'

4c. Stage and Continue

git add <resolved files>
git rebase --continue

If the rebase reports "No changes - did you forget to use 'git add'?", the commit became empty after resolution. Run git rebase --skip.

If new conflicts appear on the next commit, return to step 4a.

If at any point you are stuck (more than 2 attempts on the same file produce conflict markers, or the user asked to stop), run git rebase --abort, restore the stash, and report.

Step 5: Post-Rebase Validation

Once the rebase completes:

1. Confirm state: git status should show "nothing to commit, working tree clean" and the branch ahead of origin/$BASE.
2. If lockfiles or generated files were taken from base in Step 4, regenerate them now:
   • pnpm install if pnpm-lock.yaml was touched
   • cargo build (or cargo check) if Cargo.lock was touched
   • The project-appropriate codegen command for any generated sources Stage and amend into the relevant commit only if regeneration produced changes; otherwise leave alone.
3. If a stash was created in Step 1, ask the user before popping it (git stash pop).

Step 6: Report

Tell the user:

• The base branch and SHA you rebased onto (git rev-parse --short "origin/$BASE")
• How many commits were replayed (git rev-list --count "origin/$BASE..HEAD")
• Which files had conflicts and a one-line summary of how each was resolved
• Any follow-up they should do (e.g., "lockfile regenerated, please verify"), and whether a force-push is required (git push --force-with-lease) — but do not push unless explicitly asked

Hard Rules

• NEVER run git push --force (without --with-lease) on the user's behalf
• NEVER push at all unless the user explicitly asks
• NEVER run git rebase --skip to bypass conflicts you do not understand — only for genuinely empty commits
• NEVER discard uncommitted work without explicit confirmation
• NEVER resolve a conflict by deleting code from one side without reading both sides in full