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Ruby Debug 0101 Broken on Windows

·210 words·1 min

Since the old rails breakpointer quit working in versions of Ruby after 1.8.4, the preferred method for debugging rails has been to use ruby-debug. This is a separate gem, so to install you just do

gem install ruby-debug

However, the current version of ruby-debug (0.10.1) runs into problems on Windows, namely it doesn’t work and spews out an error message when you try to run it directly:

c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require': no such file to load -- c:/ruby/
lib/ruby/gems/1.8/gems/linecache-0.42-x86-mswin32/lib/../ext/trace_nums (LoadError)
from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
from c:/ruby/lib/ruby/gems/1.8/gems/linecache-0.42-x86-mswin32/lib/tracelines.rb:8
from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
from c:/ruby/lib/ruby/gems/1.8/gems/linecache-0.42-x86-mswin32/lib/linecache.rb:63
from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
from c:/ruby/lib/ruby/gems/1.8/gems/ruby-debug-base-0.10.1-mswin32/lib/ruby-debug-base.rb:3
from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
from c:/ruby/lib/ruby/gems/1.8/gems/ruby-debug-0.10.1/cli/ruby-debug.rb:5
from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
from c:/ruby/lib/ruby/gems/1.8/gems/ruby-debug-0.10.1/bin/rdebug:7
from c:/ruby/bin/rdebug:19:in `load'
from c:/ruby/bin/rdebug:19

I’ve found two possible ways to fix this. The first is simply to revert back to ruby-debug version 0.10.0

gem uninstall ruby-debug
gem install ruby-debug --version "=0.10.0"

The other way to fix the problem I found on a ticket in Rails Trac

In the file ruby\lib\ruby\gems\1.8\gems\linecache-0.42-x86-mswin32\lib\tracelines.rb I changed the line from

require File.join(@@SRCDIR, '..', 'ext', 'tracenums')

to

require File.join(@@SRC_DIR, '..', 'ext', 'extconf.rb')

I suppose the advantage to this method is that you have the newer version of ruby-debug with all it’s fixes, although I don’t really know what those are.