Fixup Plan

Purpose

Given uncommitted changes on a feature branch, determine which existing on-branch commit each change logically belongs to, and output the git commit --fixup commands that fold them in cleanly. This mirrors an interactive fixup helper: blame the changed lines, match them to on-branch commits, group files by target, and finish with an autosquash rebase.

Constraints

• Never create commits, tags, or rebases yourself. The user requires GPG-signed commits via a YubiKey that needs physical touch, so all git commit and git rebase commands must be left for the user to run manually.
• Only analyze and stage-plan; do not git add unless explicitly asked.
• Never target a fixup!, squash!, or amend! commit — always target the original commit.
• Beware of pagination in git and GitHub cli, set PAGER=cat and GH_PAGER=cat.

Workflow

1. Establish the branch context

Find the merge-base with the base branch and list the on-branch commits, excluding autosquash commits: