grepr - simple grep for rails projects

grepr

#!/usr/bin/env ruby

class Grepr
  def initialize(options, pattern)
    @paths = []
    @pattern = pattern
    @noregex = options.include?('n')
    @pattern = "'#{@pattern}'" if pattern.include?(' ')
    options.each_char do |opt|
      case opt
        when 'a'
          @paths = ['app/*', 'lib/*']
          break
        when 'm'
          @paths << 'app/models/*'
        when 'v'
          @paths << 'app/views/*'
        when 'c'
          @paths << 'app/controllers/*'
        when 'r'
          @paths << 'app/reports/*'
        when 'h'
          @paths << 'app/helpers/*'
        when 'l'
          @paths << 'lib/*'
        when 't'
          @paths << 'test/*'
      end
    end
  end
  
  def command
    @paths = ['app/*', 'lib/*'] if @paths.empty?
    "grep -inr#{'F' if @noregex} --colour #{@pattern} #{@paths.join(' ')}"
  end
end

def usage
  puts "Grep a rails project using common options and dirs.

Usage: grepr [OPTIONS] PATTERN
  Look through your rails project source for PATTERN using grep.
  - matches case-insensitive (-i).
  - shows line numbers in result (-n).
  - checks recursively through dirs (-r).
  - highlights PATTERN in result (--colour).
  
  Command must be issued at the root of a rails project.
  OPTIONS must be concatenated: grepr -mv user
  -a will be assumed if OPTIONS are omitted.
  PATTERN must be in quotes if it contains spaces.
  
  OPTIONS
  -n   No regex.
       Use this so special chars aren't treated as regex (eg '.').
  -a   All folders except test (app/* and lib/*)
       (any other options will be ignored)
  -m   app/models/*
  -v   app/views/*
  -c   app/controllers/*
  -r   app/reports/*
  -h   app/helpers/*
  -l   lib/*
  -t   test/*
"
  exit
end

if ARGV[0]
  if ARGV[0].start_with? '-'
    opts = ARGV.shift.delete('-')
  else
    opts = 'a'
  end
  parms = ARGV.shift
  return usage if parms.nil?
  grepr = Grepr.new(opts, parms)
  #puts grepr.command
  exec grepr.command
else
  return usage
end