Rebase Merge

rebase-merge

Merge the current branch into a target branch using rebase + fast-forward only.

$ARGUMENTS is the target branch (e.g. main). If it is empty, ask the user for the target branch and stop.

Steps

1. Run git status --short. If the working tree is dirty, inform the user and stop — do not stash or commit for them.
2. Record the current branch as the original branch: git rev-parse --abbrev-ref HEAD. If it equals the target branch, inform the user and stop. Whatever happens after this point — success, conflict abort, or fast-forward failure — the skill must end with the original branch checked out.
3. Rebase the current branch onto the target:

   git rebase <target>
   

4. If the rebase stops on conflicts, resolve them:
   • Run git status to list conflicted files.
   • Read each conflicted file, resolve the conflict markers by combining both sides' intent (favor the current branch's changes when the sides are genuinely incompatible), then git add the file.
   • Continue with git rebase --continue. Repeat until the rebase completes.
   • If a conflict cannot be resolved confidently, run git rebase --abort (this leaves the original branch checked out) and report which files were problematic.
5. Validate the rebased branch before merging — this is the exact commit the target will point to:
   • Determine the project's conventional validation command, in order of preference: instructions in CLAUDE.md, a check or test target in a Makefile, a check/test/lint script in package.json, or the language's standard (cargo test, go test ./..., pytest, etc.).
   • Run it. If validation fails, do NOT merge: report the failures and stop, leaving the rebased branch checked out so the user can fix it.
   • If no validation command can be found, tell the user validation was skipped and continue.
6. Fast-forward merge into the target:

   git checkout <target>
   git merge --ff-only <branch>
   

7. If the fast-forward merge fails (target has commits not in the rebased branch), inform the user the target moved and a fast-forward is not possible.
8. On success, run git log --oneline -3 on the target and show the user the result.
9. Return to the original branch: git checkout <branch>. Then verify with git rev-parse --abbrev-ref HEAD that the checked-out branch matches the original branch recorded in step 2; if it doesn't, check it out and inform the user.

Notes

• Do NOT push to a remote. All operations are local.
• Do NOT use git merge without --ff-only, and never create a merge commit.
• Never force-push or rewrite the target branch.
• Always finish with the original branch checked out, regardless of outcome.