test case for serialize default values.

Closes #9110

activerecord/test/cases/serialized_attribute_test.rb

@@ -1,6 +1,7 @@
 require 'cases/helper'
 require 'models/topic'
 require 'models/person'
+require 'models/traffic_light'
 require 'bcrypt'
 
 class SerializedAttributeTest < ActiveRecord::TestCase
@@ -234,4 +235,10 @@ def test_serialize_attribute_can_be_serialized_in_an_integer_column
     person = person.reload
     assert_equal(insures, person.insures)
   end
+
+  def test_regression_serialized_default_on_text_column_with_null_false
+    light = TrafficLight.new
+    assert_equal [], light.state
+    assert_equal [], light.long_state
+  end
 end

activerecord/test/fixtures/traffic_lights.yml

@@ -4,3 +4,7 @@ uk:
     - Green
     - Red
     - Orange
+  long_state:
+    - "Green, go ahead"
+    - "Red, wait"
+    - "Orange, caution light is about to switch"

activerecord/test/models/traffic_light.rb

@@ -1,3 +1,4 @@
 class TrafficLight < ActiveRecord::Base
   serialize :state, Array
+  serialize :long_state, Array
 end

activerecord/test/schema/schema.rb

@@ -685,6 +685,7 @@ def create_table(*args, &block)
   create_table :traffic_lights, :force => true do |t|
     t.string   :location
     t.string   :state
+    t.text     :long_state, :null => false
     t.datetime :created_at
     t.datetime :updated_at
   end