#!/bin/bash
#
# totally sniff every line in history to see whose
# are the lines here


path="${1:-}"
maybe_path=""
test -n "$path" && maybe_path="-- $path"

git ls-tree -r -z --name-only HEAD $maybe_path \
  | xargs -0 -n1 git blame --line-porcelain HEAD \
  | grep  "^author " \
  | sort \
  | uniq -c \
  | sort -nr