Error with Rails Edge/4 `require': cannot load such file — thread_safe

问题

Following ths instructions here for getting an app running off Rails Edge to test Rails 4: What is the best way to generate a Rails app using edge? and How to create Edge rails application?

But running into this error:

`require': cannot load such file -- thread_safe (LoadError)

Using the command:

rails new Edge --edge --skip-bundle --database=postgresql --skip-test-unit --skip-index-html

A checkout of Rails master bin dir is on my path.

I am using rbenv with ruby 1.9.3p327.

I have cleared all my installed gems out, just running bundler.

Rails 3.2.9 works fine on my system, have an app in active development.

回答1:

Issue is not having the rails gems installed (when installing via rubygems, dependencies are automatically resolved.

See https://github.com/rails/rails/pull/8589

Need to go into the cloned rails dir and run "bundle install", which will pull in the necessary gems.

来源：https://stackoverflow.com/questions/14098983/error-with-rails-edge-4-require-cannot-load-such-file-thread-safe