weekly_git_stats.rb

weekly_git_stats.rb

#!/usr/bin/env ruby
#
# Usage:
#   weekly_git_stats.rb
#   weekly_git_stats.rb 2019-01-01 2019-07-31
#
# see also: cloc --vcs git
#
require 'date'
require 'open3'

begin
  start_date = Date.parse(ARGV[0])
  end_date = Date.parse(ARGV[1])
rescue => e
  STDERR.puts "Warning: #{e.message}"
  end_date = Date.today
  start_date = end_date - 365
end

# start_str = start_date.strftime("%Y-%m-%d")
# end_str = end_date.strftime("%Y-%m-%d")
# STDERR.puts "#{start_str} -> #{end_str}"

num_weeks = 0
total_changes = 0
current_date = start_date.clone
while current_date < end_date do
  week_start_str = current_date.strftime("%Y-%m-%d")
  week_end_str = (current_date + 7).strftime("%Y-%m-%d")
  cmd = %Q(git whatchanged --since="#{week_start_str}" --until="#{week_end_str}" --shortstat)
  # puts cmd
  stdout, * = Open3.capture3(cmd)
  num_changed_lines = 0
  stdout.each_line do |line|
    matched = /([0-9]+) files changed, ([0-9]+) insertions\(\+\), ([0-9]+) deletions\(-\)/.match(line)
    if matched
      num_changed_lines += matched[2].to_i + matched[3].to_i
    end
  end
  if num_changed_lines > 0
    puts "#{week_start_str} -> #{week_end_str}: #{num_changed_lines}"
    num_weeks += 1
  end
  total_changes += num_changed_lines
  current_date += 7
end

puts "per week: #{(total_changes / num_weeks).to_f}" if num_weeks > 0