Why do I get error “undefined method `write_inheritable_attribute'” in my migration?

问题

I attempted to generate a migration like:

rails generate migration RemovefromGenotypes box:integer well:string

but then I get this error:

/usr/share/rails-ruby1.8/railties/lib/rails_generator/options.rb:32:in `default_options': undefined method `write_inheritable_attribute' for Rails::Generator::Base:Class (NoMethodError)
    from /usr/share/rails-ruby1.8/railties/lib/rails_generator/base.rb:90:in `<class:Base>'
    from /usr/share/rails-ruby1.8/railties/lib/rails_generator/base.rb:85:in `<module:Generator>'
    from /usr/share/rails-ruby1.8/railties/lib/rails_generator/base.rb:48:in `<module:Rails>'
    from /usr/share/rails-ruby1.8/railties/lib/rails_generator/base.rb:6:in `<top (required)>'
    from /home/caseyr/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
    from /home/caseyr/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
    from /usr/share/rails-ruby1.8/railties/lib/rails_generator.rb:34:in `<top (required)>'
    from /home/caseyr/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
    from /home/caseyr/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
    from /usr/share/rails-ruby1.8/railties/bin/rails:14:in `<main>'

I have no clue where to start to debug this, but would certainly appreciate it if anyone could point me in the right direction...

Thanks! --rick

回答1:

I have same issue. Use following command and problem gone

 gem install rails

This will install updated rails and all thing working find again.

回答2:

Happened to me while installing rails 2.3.14 after rails 3.2.6

It seems rails 2.3 overwrites some rails 3 files. Fixed by removing 2.3 and reinstalling 3.2

来源：https://stackoverflow.com/questions/10906472/why-do-i-get-error-undefined-method-write-inheritable-attribute-in-my-migrat

标签

ruby-on-rails-3.1