This gem re-introduces Arel code that was removed from Rails 6.1: rails/rails#36492 . The code existed in the arel gem from 4.0.0 to 9.0.0, and the rails gem from 4.0.0 to 6.0.0.
It provides a DepthFirst visitor for Arel that allows you to traverse the Arel AST, e.g. for visualizations.
Include this gem into your Gemfile:
gem 'activerecord-arel_depth_first'
This visitor makes the Arel AST enumerable, so you can do a depth-first iteration over it:
User.some_arbitrary_scope.arel.ast.each do |node|
case node
when Arel::Table
# do something for table nodes
when Arel::Nodes::Equality
# do something for equality nodes
else
# and so on ...
end
end
activerecord-arel_depth_first is released under the MIT License.