Diff ruby files

find_duplicate_methods.rb

#!/usr/bin/env ruby

require 'tempfile'

def get_methods(file_contents)
  code_for_all_methods = file_contents.scan(/((\s+?)def .*?^\2end)/m)
  code_for_all_methods.each_with_object({}) do |(code), hsh|
    method_name = code[/def (?:self\.)?(\w+)/, 1]
    hsh[method_name.to_s] = code
  end
end

def get_methods_from_file(path)
  get_methods(File.read(path))
end

def write_to_tempfile(str)
  Tempfile.open do |tempfile|
    tempfile.write(str)
    tempfile.flush
    yield tempfile.path
  end
end

def delete_tempfile(tempfile)
  tempfile.close
  tempfile.unlink
end

def diff_methods(code_a, code_b)
  write_to_tempfile(code_a) do |path_a|
    write_to_tempfile(code_b) do |path_b|
      return `diff --ignore-all-space #{path_a} #{path_b}`
    end
  end
end

first_file_path = ARGV[0]
second_file_path = ARGV[1]

first_file_methods = get_methods_from_file(first_file_path)
second_file_methods = get_methods_from_file(second_file_path)

shared_method_names = first_file_methods.keys & second_file_methods.keys

shared_method_names.each do |method_name|
  puts "#{method_name}:"
  difference = diff_methods(first_file_methods[method_name], second_file_methods[method_name])
  puts difference.chomp == "" ? "Methods are identical" : difference
end