Updated: Use https://github.com/nickolasburr/git-follow instead.

git-track

#!/bin/bash

# track: Track lifetime changes of a file (includes renames) via formatted diff log
# @todo: Better error handling, combining flags
E_NOTFOUND=85
E_BADARGS=86
FILENAME="${!#}"

# verify we're checking against a valid filename
if [[ ! -f $FILENAME ]]; then
	printf 'Usage: track {-a[--all]|-f[--first]|-i[--inline]|-l[--last]|-L[--lines]|-r[--reverse]} filename\n'
	return $E_NOTFOUND
fi

# if the only argument is a file name, set the default
# flag value to `--all` and update positional parameters
if [ "$1" == $FILENAME ]; then
	set -- "--all" $FILENAME
# if the first argument is `--lines`, verify we're receiving two line numbers
# as the following two arguments ($2 and $3), with the filename as the last argument
elif [ "$1" == "-l" ] || [ "$1" == "--lines" ]; then
	E_NUMARGS=4
	if [ $# != $E_NUMARGS ]; then
		printf 'Wrong number of arguments\nUsage: track --lines start end filename\n'
		return $E_BADARGS
	else
		set -- "--lines" $2 $3 $FILENAME
	fi
# special handling for `--last` flag which
# takes a single argument for the last n commits
elif [ "$1" == "-L" ] || [ "$1" == "--last" ]; then
	E_NUMARGS=3
	# if `--last` is given with no arguments, default to 1
	if [ "$2" == $FILENAME ]; then
		set -- "--last" 1 $FILENAME
	# if `--last` is given with 1 argument, (re)set the positional parameters
	elif [ "$3" == $FILENAME ]; then
		set -- "--last" $2 $FILENAME
	else
		printf 'Wrong number of arguments\nUsage: track --last [commits] filename\n'
		return $E_BADARGS
	fi
	# now check the argv count against what's expected
	if [ $# != $E_NUMARGS ]; then
		printf 'Wrong number of arguments\nUsage: track --last n filename\n'
		return $E_BADARGS
	fi
elif [ "$1" == "-F" ] || [ "$1" == "--func" ]; then
	E_NUMARGS=3
	# now check the argv count against what's expected
	if [ $# != $E_NUMARGS ]; then
		printf 'Wrong number of arguments\nUsage: track --func funcname filename\n'
		return $E_BADARGS
	fi
fi

# filter flag options accordingly
case $1 in
	-a|--all)
		git log --color-words --follow \
		        --format='%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset%n' \
		        --graph --no-merges \
		        --patch --stat \
		        $FILENAME
	;;
	-f|--first)
		git log --color-words --diff-filter=A \
		        --format='%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset%n' \
		        --graph --no-merges \
		        --patch --stat \
		        $FILENAME
	;;
	-F|--func)
		git log --color-words --follow \
		        --format='%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset%n' \
		        --graph -L :$2:$FILENAME \
		        --no-merges --patch --stat \
		        $FILENAME
	;;
	-i|--inline)
		git log --follow \
		        --format='%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset%n' \
		        --graph --no-merges \
		        --patch --stat \
		        $FILENAME
	;;
	-l|--last)
		git log --color-words --follow \
		        --format='%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset%n' \
		        --graph --max-count $2 \
		        --no-merges --patch --stat \
		        $FILENAME
	;;
	-L|--lines)
		git log --color-words \
		        --format='%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset%n' \
		        --graph -L $2,$3:$FILENAME \
		        --no-merges --patch --stat
	;;
	-r|--reverse)
		git log --color-words --follow \
		        --format='%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset%n' \
		        --no-merges --patch \
		        --reverse --stat \
		        $FILENAME
	;;
	*)
		printf 'Invalid flag\nUsage: track {-a[--all]|-f[--first]|-i[--inline]|-l[--last]|-L[--lines]|-r[--reverse]} filename\n'
	;;
esac