Rails Edge: check compatibility with .with

[tagliala]

Rails 7.1 will introduce .with to make CTE queries easily

There are no specs in Chronomodel that ensures that this works, we should add one

Database structure is here: https://github.com/ifad/chronomodel/blob/master/spec/support/time_machine/structure.rb

Ref: https://edgeapi.rubyonrails.org/classes/ActiveRecord/QueryMethods.html#method-i-with

/cc @dimvic

BUNDLE_GEMFILE=gemfiles/rails_edge.gemfile bundle update

BUNDLE_GEMFILE=gemfiles/rails_edge.gemfile bundle exec rspec spec/chrono_model/
Testing against Active Record 7.1.0.alpha with Arel 10.0.0

[dimvic]

CTE queries are really just queries and AR does not add magic on top of them, it is up to the implementation to use plain or temporal query.

So this will look for Post as of as_of_time, having Author that exists in the present

Post
  .as_of(as_of_time)
  .with(authors_cte: Author.all)
  .joins("inner join authors_cte on authors_cte.id = posts.author_id")
  .where(authors_cte: { name: current_author_name })

And explicitly setting as_of on the CTE scope is required to find Post as of as_of_time with Author as of as_of_time

Post
  .as_of(as_of_time)
  .with(authors_cte: Author.as_of(as_of_time).all)
  .joins("inner join authors_cte on authors_cte.id = posts.author_id")
  .where(authors_cte: { name: author_name_as_of })

I have added an example here, sorry for the mistakenly created PR against upstream.

If you think it would be good to include such test cases I can rewrite to follow the spec seeds and style.