Count Files By Extension

拡張子別にファイル数をカウントします。

file_count.rb

#! /usr/bin/env ruby
require 'pathname'

@directories = 0
@files = {}

def file_count(pathname)
  pathname.each_child  do |child|
    if child.directory?
      @directories += 1
      file_count child
    else
      add_file_by_extenstion child
    end
  end
end

def add_file_by_extenstion(pathname)
  if @files[pathname.extname].nil?
    @files[pathname.extname] = 1
  else
    @files[pathname.extname] += 1
  end
end

if ARGV[0]&.start_with? '-'
  puts <<-EOT
usage: file_count {directory}
  EOT

  exit
end

unless ARGV[0].nil?
  file_count Pathname.new(ARGV[0])
else
  file_count Pathname.new('.')
end

puts "#{@directories}\tdirectories"
@files.each do |extension, count|
  if extension == ""
    puts "#{count}\tno extension"
  else
    puts "#{count}\t#{extension}"
  end
end

実行例