Merge pull request #28479 from kamipo/evaluate_default_block_only_whe…

…n_necessary

Evaluate the default block only when necessary

activerecord/lib/active_record/associations/belongs_to_association.rb

@@ -21,8 +21,8 @@ def replace(record)
         self.target = record
       end
 
-      def default(record)
-        writer(record) if reader.nil?
+      def default(&block)
+        writer(instance_exec(&block)) if reader.nil?
       end
 
       def reset

activerecord/lib/active_record/associations/builder/belongs_to.rb

@@ -121,7 +121,7 @@ def self.add_touch_callbacks(model, reflection)
 
     def self.add_default_callbacks(model, reflection)
       model.before_validation lambda { |o|
-        o.association(reflection.name).default o.instance_exec(&reflection.options[:default])
+        o.association(reflection.name).default(&reflection.options[:default])
       }
     end
 

activerecord/lib/active_record/relation/delegation.rb

@@ -36,7 +36,7 @@ def inherited(child_class)
     # may vary depending on the klass of a relation, so we create a subclass of Relation
     # for each different klass, and the delegations are compiled into that subclass only.
 
-    delegate :to_xml, :encode_with, :length, :collect, :map, :each, :all?, :include?, :to_ary, :join,
+    delegate :to_xml, :encode_with, :length, :collect, :uniq, :each, :all?, :include?, :to_ary, :join,
              :[], :&, :|, :+, :-, :sample, :reverse, :compact, :in_groups, :in_groups_of,
              :to_sentence, :to_formatted_s, :as_json,
              :shuffle, :split, :index, to: :records