1 files changed, 3 insertions, 15 deletions
diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb
index b847933b2e..00ff20f4d7 100644
--- a/activerecord/lib/active_record/reflection.rb
+++ b/activerecord/lib/active_record/reflection.rb
@@ -657,7 +657,7 @@ module ActiveRecord
         # from calling +klass+, +reflection+ will already be set to false.
         def valid_inverse_reflection?(reflection)
           reflection &&
-            klass.name == reflection.active_record.name &&
+            klass <= reflection.active_record &&
             can_find_inverse_of_automatically?(reflection)
         end
 
@@ -1036,20 +1036,12 @@ module ActiveRecord
 
       def scopes
         scopes = @previous_reflection.scopes
-        if @previous_reflection.options[:source_type]
-          scopes + [@previous_reflection.source_type_scope]
-        else
-          scopes
-        end
+        scopes << @previous_reflection.source_type_scope
       end
 
       def join_scopes(table, predicate_builder) # :nodoc:
         scopes = @previous_reflection.join_scopes(table, predicate_builder) + super
-        if @previous_reflection.options[:source_type]
-          scopes + [@previous_reflection.source_type_scope]
-        else
-          scopes
-        end
+        scopes << @previous_reflection.source_type_scope
       end
 
       def klass
@@ -1100,10 +1092,6 @@ module ActiveRecord
         @reflection.constraints
       end
 
-      def alias_candidate(name)
-        "#{plural_name}_#{name}_join"
-      end
-
       def alias_name
         Arel::Table.new(table_name, type_caster: klass.type_caster)
       end