Add --debugger option to script/console.

Signed-off-by: Michael Koziarski <michael@koziarski.com>
[#1025 state:committed]

railties/lib/commands/console.rb

@@ -1,11 +1,13 @@
 irb = RUBY_PLATFORM =~ /(:?mswin|mingw)/ ? 'irb.bat' : 'irb'
 
 require 'optparse'
+
 options = { :sandbox => false, :irb => irb }
 OptionParser.new do |opt|
   opt.banner = "Usage: console [environment] [options]"
   opt.on('-s', '--sandbox', 'Rollback database modifications on exit.') { |v| options[:sandbox] = v }
   opt.on("--irb=[#{irb}]", 'Invoke a different irb.') { |v| options[:irb] = v }
+  opt.on("--debugger", 'Enable ruby-debugging for the console.') { |v| options[:debugger] = v }
   opt.parse!(ARGV)
 end
 
@@ -15,6 +17,17 @@ libs << " -r console_app"
 libs << " -r console_sandbox" if options[:sandbox]
 libs << " -r console_with_helpers"
 
+if options[:debugger]
+  begin
+    require 'ruby-debug'
+    libs << " -r ruby-debug"
+    puts "=> Debugger enabled"
+  rescue Exception
+    puts "You need to install ruby-debug to run the console in debugging mode. With gems, use 'gem install ruby-debug'"
+    exit
+  end
+end
+
 ENV['RAILS_ENV'] = case ARGV.first
   when "p"; "production"
   when "d"; "development"