# REG: How can we debug a ruby script **URL:** \ **Category:** Ruby\ **Created:** [March 30, 2009, 5:52pm UTC](https://www.ruby-forum.com/t/reg-how-can-we-debug-a-ruby-script/164266 "2009-03-30T17:52:58Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\ **Post date:** [March 30, 2009, 5:52pm UTC](https://www.ruby-forum.com/t/reg-how-can-we-debug-a-ruby-script/164266/1 "2009-03-30T17:52:58Z")
Hi, I want to debug a ruby script using -rdebug option. The following is the source code: with file fact.rb. Fact.rb def fact(n) return 1 if n == 0 f = 1 n.downto(1) do |i| f \*= i end return f end print fact(2), “\n” Debugging When I run the following command and type ‘n’ for debugin the next line, it is going in to some other files. As shown below. C:\ruby\samples\RubySrc-1.8.6-p111\sample\>ruby -rdebug fact.rb Debug.rb Emacs support available. c:/ruby/lib/ruby/site\_ruby/1.8/ubygems.rb:10:require ‘rubygems’ (rdb:1) list [5, 14] in c:/ruby/lib/ruby/site\_ruby/1.8/ubygems.rb 5 # All rights reserved. 6 # See LICENSE.txt for permissions. 7 #++ 8 9 =\> 10 require ‘rubygems’ (rdb:1) n c:/ruby/lib/ruby/site\_ruby/1.8/rubygems.rb:10:require ‘rbconfig’ (rdb:1) n c:/ruby/lib/ruby/1.8/i386-mswin32/rbconfig.rb:5:module Config (rdb:1) n c:/ruby/lib/ruby/1.8/i386-mswin32/rbconfig.rb:153:RbConfig = Config # compatibility for ruby-1.9 (rdb:1) n c:/ruby/lib/ruby/1.8/i386-mswin32/rbconfig.rb:154:CROSS\_COMPILING = nil unless defined? CROSS\_COMPILING (rdb:1) n c:/ruby/lib/ruby/1.8/i386-mswin32/rbconfig.rb:154:CROSS\_COMPILING = nil unless defined? CROSS\_COMPILING (rdb:1) n c:/ruby/lib/ruby/site\_ruby/1.8/rubygems.rb:12:module Gem (rdb:1) n c:/ruby/lib/ruby/site\_ruby/1.8/rubygems.rb:18:module Kernel (rdb:1)’ What is the command that iam supposed to used to debug actual source code, line by line( with out moving to other files)? Thanks and Regards, Anil kumar ---
**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\ **Post date:** [March 31, 2009, 11:13am UTC](https://www.ruby-forum.com/t/reg-how-can-we-debug-a-ruby-script/164266/2 "2009-03-31T11:13:01Z")
Something in your environment is making ruby do -rubygems (require ‘rubygems’) Perhaps the RUBYOPT environment variable is set, because I can replicate your problem like this: $ export RUBYOPT=-rubygems $ ruby -rdebug fact.rb Debug.rb Emacs support available. /usr/local/lib/site\_ruby/1.8/ubygems.rb:10:require ‘rubygems’ (rdb:1) So if this is the case, solution 1 is simply to unset the RUBYOPT variable. Solution 2 is to set a breakpoint at the start of your program. $ ruby -rdebug fact.rb Debug.rb Emacs support available. /usr/local/lib/site\_ruby/1.8/ubygems.rb:10:require ‘rubygems’ (rdb:1) b fact.rb:1 Set breakpoint 1 at fact.rb:1 (rdb:1) cont Breakpoint 1, toplevel at fact.rb:1 fact.rb:1:def fact(n) (rdb:1) n fact.rb:9:print fact(2), “\n” (rdb:1) n 2 $ Solution 3 is to require rubygems _before_ requiring debug, because when it has been required once, it won’t be required again: $ ruby -rubygems -rdebug fact.rb Debug.rb Emacs support available. fact.rb:1:def fact(n) (rdb:1) This third one probably involves the least work. ---
**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\ **Post date:** [April 19, 2009, 11:43am UTC](https://www.ruby-forum.com/t/reg-how-can-we-debug-a-ruby-script/164266/3 "2009-04-19T11:43:53Z")
Hi, Using the below method mention the below mail, I was successfully able to run and debug the script. But when I run unittest class, the flow goes into testcase case class as below. Testscript require “test/unit” class TestSimpleNumber \< Test::Unit::TestCase def test\_simple assert\_equal(“abc”, “abc” ) end def test\_typecheck assert\_equal(“abc”, “abc” ) end def test\_failure assert\_equal(“abc”, “abc” ) end End Execution: C:\ruby\>ruby -rubygems -rdebug unittest.rb Debug.rb Emacs support available. unittest.rb:1:require “test/unit” (rdb:1) b 6 Set breakpoint 1 at unittest.rb:6 (rdb:1) cont Loaded suite unittest Started .Breakpoint 1, test\_simple at unittest.rb:6 unittest.rb:6: assert\_equal(“abc”, “abc” ) (rdb:1) n c:/ruby/lib/ruby/1.8/test/unit/testcase.rb:85: begin (rdb:1) n c:/ruby/lib/ruby/1.8/test/unit/testcase.rb:86: teardown (rdb:1) n c:/ruby/lib/ruby/1.8/test/unit/testcase.rb:94: result.add\_run (rdb:1) n c:/ruby/lib/ruby/1.8/test/unit/testcase.rb:95: yield(FINISHED, name) (rdb:1) n c:/ruby/lib/ruby/1.8/test/unit/ui/testrunnermediator.rb:47: notify\_listeners(channel, value) (rdb:1) Please help me in this regard. Thanks, Anil kumar. ---
**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\ **Post date:** [April 19, 2009, 5:06pm UTC](https://www.ruby-forum.com/t/reg-how-can-we-debug-a-ruby-script/164266/4 "2009-04-19T17:06:01Z")
Tips for posting: Don’t reply to someone else’s thread and change the name. Start a new thread with your New button. Now to your problem - is this a typo? > End The code should not compile with that error, but your stack trace implies you started executing. However… > C:\ruby\>ruby -rubygems -rdebug unittest.rb You might need -rrubygems. ## Next, report what happens without the -rdebug. I never debug unit tests they tend to help you avoid excess debugging! ---
**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\ **Post date:** [April 19, 2009, 5:20pm UTC](https://www.ruby-forum.com/t/reg-how-can-we-debug-a-ruby-script/164266/5 "2009-04-19T17:20:42Z")
Phlip wrote: > Tips for posting: > > Don’t reply to someone else’s thread and change the name. Start a new thread > with your New button. My bad! I didn’t notice the thread was the same. Carry on! (; ---
**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\ **Post date:** [April 19, 2009, 7:24pm UTC](https://www.ruby-forum.com/t/reg-how-can-we-debug-a-ruby-script/164266/6 "2009-04-19T19:24:17Z")
Phlip wrote: > > C:\ruby\>ruby -rubygems -rdebug unittest.rb > > You might need -rrubygems. -rubygems is correct (the file “ubygems.rb” exists for this purpose) > Next, report what happens without the -rdebug. I never debug unit tests The problem may be that Test::Unit does strange stuff with atexit to start the tests. I’m afraid I don’t have a good solution for using -rdebug with Test::Unit. Try writing a separate standalone program which replicates the problem. Regards, Brian.