git-ls-unmerged

#!/usr/bin/env bash
# List branches (excluding release branches) that haven't been merged to the
# branch given as the first argument yet (default main). Accepts "git
# branch" options like -r/-a.

BRANCH=main
OPTS=""

while (( $# >= 1 )); do
    case "$1" in
        -*) OPTS="$1" ;;
        *)  BRANCH="$1" ;;
    esac
    shift
done

git branch $OPTS --no-merged=${BRANCH} | \
    sed -r -e 's/^[ *] //' | \
    grep -E -v '^(\(HEAD|release-)' | \
    xargs -L1 --no-run-if-empty \
        git --no-pager log --pretty=tformat:'%C(auto,yellow)%h%Creset %C(auto,blue)%ai%Creset %C(auto)%d%Creset %s' -1