Autoloading without Rails?

[jacob-carlborg]

When installing rspec-rails, adding the gem and running rails generate rspec:install. rspec-rails will create some files, among them spec_helper.rb and rails_helper.rb. As far as I understand, the reason for having two separate files is to be able to avoid booting the whole Rails applications when testing parts of the application that does not depend on Rails. Then you'll only require the spec_helper file in those tests that test things that don't depends on Rails.

My question is then, does anyone use this? How are you dealing with requiring files? Usually in a Rails application you don't need to use require because Rails autoloads your files. But when Rails is not booted there's nothing that autoloads the files. Are you adding require to your files? Ending up with some files needing require and some not. Do you manually configure Zeitwerk in spec_helper to allow to continue using the autoloader. How does that then work when requiring rails_helper that will boot the Rails application and also configure Zeitwerk?

[JonRowe]

If you run the whole suite you will end up requiring rails_helper and everything is "as normal", if you run an individual spec file which just requires spec_helper and you haven't setup Ruby's own autoload, typically I'd recommend you require just the files you need in the spec

[jacob-carlborg]

Does this answer your initial question?

No, I don't think I have got a clear answer.

[jacob-carlborg]

You can solve this in the files, but given in reality you will be relying on zeitwerk its best to just require b, then a, in the spec for A

Seems like a bad idea. Then the test would start relying on implementation details.

Thats not at all true, we use autoload for example to require

If you use an autoloader, there's no problem. But if you don't, there's definitely a problem.

Depending on what you mean, if you mean booting the application there is in the form of config/environment.rb

I mean when not booting the Rails application. That's what this whole discussion is about.

if you mean for zeitwerk et al autoloading there is not and you shouldn't be using spec_helper for those scenarios..
Loading spec helper only is for things where you control the load sequence

That's disappointing 😞.

[jacob-carlborg]

I tried to set up Zeitwerk in spec_helper and run into a problem. When running tests in multiple files and some require spec_helper and some require rails_helper. There can only be one autoloader for a given path, Zeitwerk raises an exception if two autoloaders (one from spec_helper and one from Rails`) tries to manage the same path. I did manage to find a workaround, but it feels ugly.

This whole idea of splitting up the files does not seem to work out that well in practice.

[JonRowe]

Thats why I said you need to not use split helpers for Zeitwerk, and the same holds true for most gems that integrate tightly with Rails.

Splitting the spec helpers is for people who are comfortable without e.g. zeitwerk, if you are working with "PORO" (plain old ruby object) codebases within Rails apps it offers an easy way to run plain rspec tests without Rails.

[jacob-carlborg]

I guess the last reply answers my question.