The subset_conditions plugin creates an additional *_conditions method for every subset created, which returns the filter conditions the subset uses. This can be useful if you want to use the conditions for a separate filter or combine them with OR.

Usage:

  # Add subset_conditions in the Album class
  Album.plugin :subset_conditions

  # This will now create a published_conditions method
  Album.dataset_module do
    subset :published, published: true
  end

  Album.where(Album.published_conditions).sql
  # SELECT * FROM albums WHERE (published IS TRUE)

  Album.exclude(Album.published_conditions).sql
  # SELECT * FROM albums WHERE (published IS NOT TRUE)

  Album.where(Album.published_conditions | {ready: true}).sql
  # SELECT * FROM albums WHERE ((published IS TRUE) OR (ready IS TRUE))