brew/Library/Homebrew/debrew.rb

require 'debrew/menu'
require 'debrew/raise_plus'
require 'set'

unless ENV['HOMEBREW_NO_READLINE']
  begin
    require 'rubygems'
    require 'ruby-debug'
  rescue LoadError
  end

  require 'debrew/irb'
end

class Object
  include RaisePlus
end

module ResourceDebugger
  def stage(target=nil, &block)
    return super if target

    super do
      begin
        block.call(self)
      rescue Exception => e
        if ARGV.debug?
          debrew e
        else
          raise
        end
      end
    end
  end
end

$debugged_exceptions = Set.new

def debrew(exception, formula=nil)
  raise exception unless $debugged_exceptions.add?(exception)

  puts "#{exception.backtrace.first}"
  puts "#{Tty.red}#{exception.class.name}#{Tty.reset}: #{exception}"

  begin
    again = false
    choose do |menu|
      menu.prompt = "Choose an action: "
      menu.choice(:raise) { original_raise exception }
      menu.choice(:ignore) { exception.restart } if exception.continuation
      menu.choice(:backtrace) { puts exception.backtrace; again = true }
      menu.choice(:debug) do
        puts "When you exit the debugger, execution will continue."
        exception.restart { debugger }
      end if Object.const_defined?(:Debugger)
      menu.choice(:irb) do
        puts "When you exit this IRB session, execution will continue."
        exception.restart do
          # we need to capture the binding after returning from raise
          set_trace_func proc { |event, file, line, id, binding, classname|
            if event == 'return'
              set_trace_func nil
              IRB.start_within(binding)
            end
          }
        end
      end if Object.const_defined?(:IRB) && exception.continuation
      menu.choice(:shell) do
        puts "When you exit this shell, you will return to the menu."
        interactive_shell formula
        again=true
      end
    end
  end while again
end