git-timelog.rb

# git time log
# by NK
# usage "ruby git-timelog.rb" in git repository
#
# based on 
# Simple Git Analyzer
#
# WORK IN PROGRESS :) 
#
# Tobin Harris (tobin@tobinharris.com)
# http://tobinharris.com 
# http://engineroomapps.com 
# Class to analyze git log
require "active_support/all"
require 'rubygems'
class Gitalyzer  
  
  # scrape the Git log for current directory and 
  # make into a hash we can fart about with using Ruby
  def log_to_hash   
    docs = []
    cmd = "git log --pretty='%cn|%cd|%s'"
    res = `#{cmd}`   
    res.each_line do |line|
      parts = line.split('|')
      docs << {:username=>parts[0], :datetime=>DateTime.parse(parts[1]), :subject=>parts[2]}
    end   

    return  {
      :users=> docs.map{|r| r[:username]}.uniq,
      :dates=> docs.map{|r| r[:date]}.uniq,
      :records => docs
    }
  end
end   

# Sample Report that works with the record
def output_summary_report(res)  
  # Report how many commits over time
  puts "User, Total hours, Avg interval"
  res[:users].each do |user|
    times_for_user = res[:records].select{|r| r[:username]==user}.map{|r| r[:datetime]}
    prev_time = nil
    total_hours = 0
    total_intervals = 0
    times_for_user.reverse.each do |time|
      if prev_time
        span_in_hours = ((time.to_i-prev_time.to_i).to_f/3600.0).round(2)
        if span_in_hours<3
          total_hours += span_in_hours
          total_intervals += 1
        end
      end
      prev_time = time.dup
    end
    avg_interval=0
    avg_interval=(total_hours/total_intervals).round(2) if total_intervals>0

    puts "#{user}, #{total_hours.round(2)}, #{avg_interval}"
  end      
end       

Dir.chdir($1 || '.')
g = Gitalyzer.new
res = g.log_to_hash
output_summary_report(res)

shows work hours statistics by adding intervals between commits (all intervals lower than 3 hours)

very approximate, first interval can't be counted this way of cause

seems this stats break when you do rebase