1 files changed, 11 insertions, 9 deletions
diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb
index 268cec6160..51f6a009db 100644
--- a/activerecord/lib/active_record/attribute_methods.rb
+++ b/activerecord/lib/active_record/attribute_methods.rb
@@ -186,8 +186,7 @@ module ActiveRecord
       end
 
       # Returns the column object for the named attribute.
-      # Returns a +ActiveRecord::ConnectionAdapters::NullColumn+ if the
-      # named attribute does not exist.
+      # Returns nil if the named attribute does not exist.
       #
       #   class Person < ActiveRecord::Base
       #   end
@@ -197,12 +196,17 @@ module ActiveRecord
       #   # => #<ActiveRecord::ConnectionAdapters::SQLite3Column:0x007ff4ab083980 @name="name", @sql_type="varchar(255)", @null=true, ...>
       #
       #   person.column_for_attribute(:nothing)
-      #   # => #<ActiveRecord::ConnectionAdapters::NullColumn:0xXXX @name=nil, @sql_type=nil, @cast_type=#<Type::Value>, ...>
+      #   # => nil
       def column_for_attribute(name)
-        name = name.to_s
-        columns_hash.fetch(name) do
-          ConnectionAdapters::NullColumn.new(name)
+        column = columns_hash[name.to_s]
+        if column.nil?
+          ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
+            `column_for_attribute` will return a null object for non-existent columns
+            in Rails 5.0. If you would like to continue to receive `nil`, you should
+            instead call `model.class.columns_hash[name]`
+          MESSAGE
         end
+        column
       end
     end
 
@@ -271,9 +275,7 @@ module ActiveRecord
     #   person.attributes
     #   # => {"id"=>3, "created_at"=>Sun, 21 Oct 2012 04:53:04, "updated_at"=>Sun, 21 Oct 2012 04:53:04, "name"=>"Francesco", "age"=>22}
     def attributes
-      attribute_names.each_with_object({}) { |name, attrs|
-        attrs[name] = read_attribute(name)
-      }
+      @attributes.to_hash
     end
 
     # Returns an <tt>#inspect</tt>-like string for the value of the