2 files changed, 8 insertions, 13 deletions
diff --git a/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb b/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb
index 6ad4c75fb5..2072f93194 100644
--- a/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb
+++ b/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb
@@ -62,7 +62,7 @@ module ActiveRecord::Associations::Builder # :nodoc:
 
     def middle_reflection(join_model)
       middle_name = [lhs_model.name.downcase.pluralize,
-                     association_name].join("_").gsub("::", "_").to_sym
+                     association_name.to_s].sort.join("_").gsub("::", "_").to_sym
       middle_options = middle_options join_model
 
       HasMany.create_reflection(lhs_model,
diff --git a/activerecord/lib/active_record/associations/builder/has_one.rb b/activerecord/lib/active_record/associations/builder/has_one.rb
index 27ebe8cb71..db8393930e 100644
--- a/activerecord/lib/active_record/associations/builder/has_one.rb
+++ b/activerecord/lib/active_record/associations/builder/has_one.rb
@@ -32,15 +32,12 @@ module ActiveRecord::Associations::Builder # :nodoc:
       end
     end
 
-    def self.touch_record(o, name, touch)
-      record = o.send name
+    def self.touch_record(record, name, touch)
+      instance = record.send(name)
 
-      return unless record && record.persisted?
-
-      if touch != true
-        record.touch(touch)
-      else
-        record.touch
+      if instance&.persisted?
+        touch != true ?
+          instance.touch(touch) : instance.touch
       end
     end
 
@@ -48,11 +45,9 @@ module ActiveRecord::Associations::Builder # :nodoc:
       name  = reflection.name
       touch = reflection.options[:touch]
 
-      callback = lambda { |record|
-        HasOne.touch_record(record, name, touch)
-      }
-
+      callback = -> (record) { HasOne.touch_record(record, name, touch) }
       model.after_create callback, if: :saved_changes?
+      model.after_create_commit { association(name).reset_negative_cache }
       model.after_update callback, if: :saved_changes?
       model.after_destroy callback
       model.after_touch callback