Question

I am trying to run a Rails application, but I am getting the following output:

ruby script/server 
=> Booting Mongrel
=> Rails 2.3.4 application starting on http://0.0.0.0:3000
/home/umar/.rvm/gems/ruby-1.8.6-head/gems/rails-2.3.4/lib/rails/gem_dependency.rb:119:Warning: Gem::Dependency#version_requirements is deprecated and will be removed on or after August 2010.  Use #requirement
/home/umar/.rvm/gems/ruby-1.8.6-head/gems/haml-2.0.0/lib/haml/helpers/action_view_mods.rb:46:in `alias_method': undefined method `capture_erb_with_buffer' for module `ActionView::Helpers::CaptureHelper' (NameError)
    from /home/umar/.rvm/gems/ruby-1.8.6-head/gems/haml-2.0.0/lib/haml/helpers/action_view_mods.rb:46
    from /home/umar/.rvm/rubies/ruby-1.8.6-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
    from /home/umar/.rvm/rubies/ruby-1.8.6-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
    from /home/umar/.rvm/gems/ruby-1.8.6-head/gems/activesupport-2.3.4/lib/active_support/dependencies.rb:156:in `require'
    from /home/umar/.rvm/gems/ruby-1.8.6-head/gems/activesupport-2.3.4/lib/active_support/dependencies.rb:521:in `new_constants_in'
    from /home/umar/.rvm/gems/ruby-1.8.6-head/gems/activesupport-2.3.4/lib/active_support/dependencies.rb:156:in `require'
    from /home/umar/.rvm/gems/ruby-1.8.6-head/gems/haml-2.0.0/lib/haml/helpers.rb:1
    from /home/umar/.rvm/rubies/ruby-1.8.6-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
     ... 34 levels...
    from /home/umar/.rvm/gems/ruby-1.8.6-head/gems/rails-2.3.4/lib/commands/server.rb:84
    from /home/umar/.rvm/rubies/ruby-1.8.6-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
    from /home/umar/.rvm/rubies/ruby-1.8.6-head/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
    from script/server:3

Here is the output of my gem list command:

gem list

*** LOCAL GEMS ***

actionmailer (2.3.4)
actionpack (2.3.4)
activerecord (2.3.4)
activerecord-jdbc-adapter (1.1.1)
activerecord-jdbcmysql-adapter (1.1.1)
activeresource (2.3.4)
activesupport (2.3.4)
builder (3.0.0)
cgi_multipart_eof_fix (2.5.0)
daemons (1.1.3)
fastthread (1.0.7)
gem_plugin (0.2.3)
haml (2.0.0)
jdbc-mysql (5.1.13)
mongrel (1.1.5)
rack (1.0.1)
rails (2.3.4)
rake (0.8.7)
rspec (1.3.1)
rspec-rails (1.3.3)
will_paginate (2.2.2)

and my gem -v is 1.3.7

How can I fix this error?

Answer 1

This is definitely an issue with using the older version of haml. Haml 2.0 makes use of this method capture_erb_with_buffer which is not present in versions of Rails beyond 2.1.0.

http://apidock.com/rails/ActionView/Helpers/CaptureHelper/capture_erb_with_buffer

Be sure to upgrade and install using the haml –rails command inside the project root after the proper gem is installed.