git-timetracker.sh

#!/usr/bin/env bash
# Git Timetracker. Copyright Kevin van Zonneveld (kvz.io)
# License under MIT
#
# This file
#
#  - can be run inside a git repository to get a list on what hours work took place (for billing)
#  - takes 1 argument: since. It defaults to "2 months"
#
# Usage:
#
#  cd repo
#  git-timetracker.sh 1 month
#
# Remarks:
#
#  - Since we can't use a custom dateformat but really want to, the hack is to
#    use iso format, and add backspace characters (%x08)
#
# Possible output:
#
#  2013-03-30 14:02 4bf9607 [email protected] Allow the egrep to fail without bailing out
#  2013-03-28 01:29 9120b9e [email protected] When cron fails, fallback to fallback nameservers :) Fixes #1
#  2013-03-27 13:42 d0b0df2 [email protected] Improve docs
#  2013-03-27 13:10 68c4314 [email protected] Initial import of dns-failover.sh

set -o pipefail
set -o errexit
set -o nounset
# set -o xtrace

# Optionally set how long to travel back in time
since="${@:-2 months}"

git --no-pager log \
  --date=iso \
  --since="${since}" \
  --date-order \
  --full-history \
  --all \
  --pretty=tformat:"%C(cyan)%ad%x08%x08%x08%x08%x08%x08%x08%x08%x08 %C(bold red)%h %C(bold blue)%<(22)%ae %C(reset)%s"

A nice trick is to add it to your ~/.gitconfig as an alias:

[alias] 
	timetrack = "!f() { \
         git --no-pager log \
		 	--date=iso \
		 	--since="${1-2 months}$" \
			"${2}" \
		 	--date-order \
		 	--full-history \
		 	--all \
			--pretty=tformat:'%C(cyan)%ad%x08%x08%x08%x08%x08%x08%x08%x08%x08 %C(bold red)%h %C(bold blue)%<(22)%ae %C(reset)%s'; \
       }; f"

You can then type git timetrack, git timetrack "1 day", git timetrack "1 month" --reverse (the arguments are positional, so the duration is required in this case) in any git repository!