git-commit-fixup-ask

#!/usr/bin/env bash

if ! [ -d .git ]; then
    echo "Not a git repository";
    exit 1;
fi

if git diff --cached --quiet --exit-code; then
    echo "Nothing to commit";
    exit 1;
fi

relativeToHead=0;
for commitId in `git --no-pager log --format=%H "$(git get-main-branch)...HEAD"`; do
    commitMessage=$(git --no-pager log --format=%B -n 1 $commitId)
    if [[ ${commitMessage:0:7} == "fixup! " ]] || [[ ${commitMessage:0:8} == "squash! " ]]; then
        ((relativeToHead++));
        continue;
    fi

    git --no-pager log --pretty="format:${relativeToHead}.  %Cred%h%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset" --date=relative -n1 $commitId;
    echo
    for filename in `git --no-pager diff --cached --name-only;`; do
        git --no-pager diff --stat=160 --color "$commitId" "$commitId^" -- "$filename" | head -n 1;
    done

    ((relativeToHead++));
done
if [ "$relativeToHead" -eq 0 ]; then
    echo "no commits in branch found using $(git get-main-branch)...HEAD range";
    exit 1;
fi
((relativeToHead--))

echo;
read -p "Pick a commit [0..${relativeToHead}]: " targetCommit

if [ -z "${targetCommit##*[!0-9]*}" ]; then
    echo "expected a number in range [0..${relativeToHead}]";
    exit 2;
fi
if [ ! "$targetCommit" -ge 0 -o ! "$targetCommit" -le "$relativeToHead" ]; then
    echo "expected a number in range [0..${relativeToHead}]";
    exit 3;
fi

git commit --fixup "HEAD~$targetCommit"