"Unable to autoload constant" using rspec but not rails - ruby-on-rails

Question

I've this file which I would like to test.
app/workers/station/http.rb
module Worker
module Station
class HTTP
# ...
end
end
end
This is my spec file.
spec/workers/station/http_spec.rb
describe Worker::Station::HTTP do
it "should do something" do
end
end
The problem now is that I'm getting the following error when running the spec file using rspec.
rspec spec/workers/station/http_spec.rb
/Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/activesupport-4.0.4/lib/active_support/dependencies.rb:464:in `load_missing_constant': Unable to autoload constant Station::HTTP, expected app/workers/station/http.rb to define it (LoadError)
from /Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/activesupport-4.0.4/lib/active_support/dependencies.rb:184:in `const_missing'
from spec/workers/station/http_spec.rb:3:in `<top (required)>'
from /Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/activesupport-4.0.4/lib/active_support/dependencies.rb:223:in `load'
from /Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/activesupport-4.0.4/lib/active_support/dependencies.rb:223:in `block in load'
from /Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/activesupport-4.0.4/lib/active_support/dependencies.rb:214:in `load_dependency'
from /Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/activesupport-4.0.4/lib/active_support/dependencies.rb:223:in `load'
from /Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/rspec-core-2.14.8/lib/rspec/core/configuration.rb:896:in `block in load_spec_files'
from /Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/rspec-core-2.14.8/lib/rspec/core/configuration.rb:896:in `each'
from /Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/rspec-core-2.14.8/lib/rspec/core/configuration.rb:896:in `load_spec_files'
from /Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/rspec-core-2.14.8/lib/rspec/core/command_line.rb:22:in `run'
from /Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/rspec-core-2.14.8/lib/rspec/core/runner.rb:80:in `run'
from /Users/linus/.rvm/gems/ruby-2.0.0-p247#global/gems/rspec-core-2.14.8/lib/rspec/core/runner.rb:17:in `block in autorun'
from /Users/linus/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/site_ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require'
from /Users/linus/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/site_ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require'
The strange thing is that everyting works in the console.
$ rails c
[1] pry(main)> Worker::Station::HTTP
=> Worker::Station::HTTP
Why is this happening using rspec and not in rails and how would I fix it?
I'm using
rails (4.0.4)
rspec (2.14.1)

Answer 1

As jfornoff suggests you could add a require statement to the spec with a statement something like the following:
require "app/workers/station/http"
But if you are using the Spring Rails application preloader and the above doesn't resolve the problem, you could also check to see if Spring needs to be restarted. You can test running the spec without using Spring as follows:
bundle exec rspec spec/workers/station/http_spec.rb
... or ...
spring stop # or bin/spring stop
rspec spec/workers/station/http_spec.rb

Answer 2

The app/workers path is not being autoloaded by rspec because it is not standard rails layout, you can add an autoload line to your spec_helper or require the file in the spec directly!

Answer 3

Note: If solutions above/below do not work for you.
In Rails 4.1 and 4.2 I got similar error while trying to run the following command
$ spring rspec spec/classes/email_parser/email_provider_spec.rb:163
even tried
$ rspec spec/classes/email_parser/email_provider_spec.rb:163
Unable to autoload constant Account::Onboarding
Called from /Users/john/.rbenv/versions/2.3.8/lib/ruby/gems/2.3.0/gems/activesupport-4.2.11.3/lib/active_support/dependencies.rb:238:in `block in load_dependency'
/Users/john/.rbenv/versions/2.3.8/lib/ruby/gems/2.3.0/gems/activesupport-4.2.11.3/lib/active_support/dependencies.rb:495:in `load_missing_constant': Unable to autoload constant Account::Onboarding, expected /Users/john/Projects/Core/app/models/account/onboarding.rb to define it (LoadError)
from /Users/john/.rbenv/versions/2.3.8/lib/ruby/gems/2.3.0/gems/activesupport-4.2.11.3/lib/active_support/dependencies.rb:184:in `const_missing'
from /Users/john/Projects/Core/app/models/account.rb:9:in `<class:Account>'
from /Users/john/Projects/Core/app/models/account.rb:3:in `<top (required)>'
Cause
Turns out, I recently restarted my Mac and forgot to start the PG server. Not finding the PG server to respond to port 5432, the app seems to be crashing with logs that do not make any sense.
Solution that worked for me
I started the PG server.
# For Mac
$ pg_ctl -D /usr/local/var/postgresql#11 start
# For Linux
$ sudo service postgresql start