Properly copy nested bind values from subqueried relations

This is cropping up all over the place. After a brief dive, I'm really
not sure why we have `arel.bind_values` at all. A cursory grep didn't
reveal where they're actually being assigned (it's definitely in AR, not
in Arel). I'd like to dig further into it, as I'm fairly certain we
don't actually need it, we just need a way for the predicate builder to
communicate merged binds upstream.

Fixes #18414

2 files changed, 22 insertions, 12 deletions

diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index f054e17017..d6e6cb4d05 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -1154,13 +1154,11 @@ module ActiveRecord
       end
     end
 
-    # This function is recursive just for better readablity.
-    # #where argument doesn't support more than one level nested hash in real world.
     def add_relations_to_bind_values(attributes)
       if attributes.is_a?(Hash)
         attributes.each_value do |value|
           if value.is_a?(ActiveRecord::Relation)
-            self.bind_values += value.bind_values
+            self.bind_values += value.arel.bind_values + value.bind_values
           else
             add_relations_to_bind_values(value)
           end
diff --git a/activerecord/test/cases/relation/where_test.rb b/activerecord/test/cases/relation/where_test.rb
index d675953da6..b0573579da 100644
--- a/activerecord/test/cases/relation/where_test.rb
+++ b/activerecord/test/cases/relation/where_test.rb
@@ -1,13 +1,15 @@
 require "cases/helper"
-require 'models/author'
-require 'models/price_estimate'
-require 'models/treasure'
-require 'models/post'
-require 'models/comment'
-require 'models/edge'
-require 'models/topic'
-require 'models/binary'
-require 'models/vertex'
+require "models/author"
+require "models/binary"
+require "models/cake_designer"
+require "models/chef"
+require "models/comment"
+require "models/edge"
+require "models/post"
+require "models/price_estimate"
+require "models/topic"
+require "models/treasure"
+require "models/vertex"
 
 module ActiveRecord
   class WhereTest < ActiveRecord::TestCase
@@ -26,6 +28,16 @@ module ActiveRecord
       }
     end
 
+    def test_where_copies_arel_bind_params
+      chef = Chef.create!
+      CakeDesigner.create!(chef: chef)
+
+      cake_designers = CakeDesigner.joins(:chef).where(chefs: { id: chef.id })
+      chefs = Chef.where(employable: cake_designers)
+
+      assert_equal [chef], chefs.to_a
+    end
+
     def test_rewhere_on_root
       assert_equal posts(:welcome), Post.rewhere(title: 'Welcome to the weblog').first
     end