when i use debugger in the spec , after type irb , it raise error below
INTERNAL ERROR!!! wrong number of arguments (2 for 1)
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/irb/extend-command.rb:157:in
respond_to?' /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/irb/extend-command.rb:157:ininstall_alias_method’
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/irb/extend-command.rb:179:in
extend_object' /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/irb/extend-command.rb:178:ineach’
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/irb/extend-command.rb:178:in
extend_object' /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/irb.rb:93:inextend’
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/irb.rb:93:in
initialize' /Library/Ruby/Gems/1.8/gems/ruby-debug-0.10.1/cli/ruby-debug/commands/irb.rb:24:innew’
/Library/Ruby/Gems/1.8/gems/ruby-debug-0.10.1/cli/ruby-debug/commands/irb.rb:24:in
start_session' /Library/Ruby/Gems/1.8/gems/ruby-debug-0.10.1/cli/ruby-debug/commands/irb.rb:62:inexecute’
/Library/Ruby/Gems/1.8/gems/ruby-debug-0.10.1/cli/ruby-debug/processor.rb:272:in
one_cmd' /Library/Ruby/Gems/1.8/gems/ruby-debug-0.10.1/cli/ruby-debug/processor.rb:259:inprocess_commands’
/Library/Ruby/Gems/1.8/gems/ruby-debug-0.10.1/cli/ruby-debug/processor.rb:258:in
each' /Library/Ruby/Gems/1.8/gems/ruby-debug-0.10.1/cli/ruby-debug/processor.rb:258:inprocess_commands’
/Library/Ruby/Gems/1.8/gems/ruby-debug-0.10.1/cli/ruby-debug/processor.rb:251:in
catch' /Library/Ruby/Gems/1.8/gems/ruby-debug-0.10.1/cli/ruby-debug/processor.rb:251:inprocess_commands’
/Library/Ruby/Gems/1.8/gems/ruby-debug-0.10.1/cli/ruby-debug/processor.rb:171:in
__at_line' (eval):5:inat_line’
(eval):3:in synchronize' (eval):3:inat_line’
/Library/Ruby/Gems/1.8/gems/ruby-debug-base-0.10.1/lib/ruby-debug-base.rb:52:in
at_line' ./spec/models/diagnosis_spec.rb:16 /Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/example/example_methods.rb:84:ininstance_eval’
/Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/example/example_methods.rb:84:in
run_with_description_capturing' /Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/example/example_methods.rb:21:inexecute’
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/timeout.rb:48:in
timeout' /Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/example/example_methods.rb:18:inexecute’
/Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/example/example_group_methods.rb:303:in
execute_examples' /Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/example/example_group_methods.rb:302:ineach’
/Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/example/example_group_methods.rb:302:in
execute_examples' /Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/example/example_group_methods.rb:130:inrun’
/Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/runner/example_group_runner.rb:22:in
run' /Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/runner/example_group_runner.rb:21:ineach’
/Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/runner/example_group_runner.rb:21:in
run' /Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/runner/options.rb:106:inrun_examples’
/Users/sunsware/sandbox/dxj/vendor/plugins/rspec/lib/spec/runner/command_line.rb:19:in
`run’
./script/spec:4…