hide join_constraints inside the JoinDependency object

2 files changed, 7 insertions, 8 deletions

diff --git a/activerecord/lib/active_record/associations/join_dependency.rb b/activerecord/lib/active_record/associations/join_dependency.rb
index 433855ceea..4d1f7a1041 100644
--- a/activerecord/lib/active_record/associations/join_dependency.rb
+++ b/activerecord/lib/active_record/associations/join_dependency.rb
@@ -75,20 +75,20 @@ module ActiveRecord
         self
       end
 
-      def join_associations
-        join_root.drop 1
-      end
-
       def reflections
-        join_associations.map(&:reflection)
+        join_root.drop(1).map(&:reflection)
       end
 
       def join_relation(relation)
-        join_associations.inject(relation) do |rel,association|
+        join_root.drop(1).inject(relation) do |rel,association|
           association.join_relation(rel)
         end
       end
 
+      def join_constraints
+        join_root.drop(1).flat_map(&:join_constraints)
+      end
+
       def columns
         join_root.collect { |join_part|
           table = join_part.aliased_table
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index 9fcb6db726..e1efc6a189 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -952,8 +952,7 @@ module ActiveRecord
 
       join_dependency.graft(*stashed_association_joins)
 
-      joins = join_dependency.join_associations.map!(&:join_constraints)
-      joins.flatten!
+      joins = join_dependency.join_constraints
 
       joins.each { |join| manager.from(join) }