callers.rb

#!/usr/bin/ruby -w

$: << "../../sexp_processor/dev/lib"
$: << "lib"

require "ruby_parser"
require "sexp_processor"

require "set"

class Callers < MethodBasedSexpProcessor
  def self.expand_dirs_to_files *dirs
    extensions = %w[rb rake]

    dirs.flatten.map { |p|
      if File.directory? p then
        Dir[File.join(p, '**', "*.{#{extensions.join(',')}}")]
      else
        p
      end
    }.flatten.sort
  end

  attr_accessor :known, :called

  def initialize
    self.known = Hash.new { |h,k| h[k] = Set.new }
    self.called = Set.new
    super
  end

  def process_defn sexp
    super do
      method_name = self.method_name[1..-1].to_sym
      known[method_name] << klass_name
      process_until_empty sexp
    end
  end

  def process_defs sexp
    super do
      method_name = self.method_name[2..-1].to_sym
      known[method_name] << klass_name
      process_until_empty sexp
    end
  end

  def process_call sexp
    method_name = sexp[2]
    method_name = :initialize if method_name == :new
    called << method_name

    sexp
  end

  def report
    not_called = known.keys - called.to_a

    by_class = Hash.new { |h,k| h[k] = [] }

    not_called.each do |meth|
      known[meth].each do |klass|
        by_class[klass] << meth
      end
    end

    puts "These methods MIGHT not be called:"
    puts

    by_class.sort_by(&:to_s).each do |klass, meths| # :main is a symbol, so to_s
      puts klass
      puts "  #{meths.sort.join "\n  "}"
    end
  end
end

if $0 == __FILE__ then
  callers = Callers.new
  parser = RubyParser.new

  Callers.expand_dirs_to_files(ARGV).each do |path|
    warn "processing: #{path}"
    callers.process parser.process File.read path
  end

  callers.report
end