attribute_methods_test.rb

require "cases/helper"
require 'models/topic'
require 'models/minimalistic'

class AttributeMethodsTest < ActiveRecord::TestCase
  fixtures :topics
  
  def setup
    @old_matchers = ActiveRecord::Base.send(:attribute_method_matchers).dup
    @target = Class.new(ActiveRecord::Base)
    @target.table_name = 'topics'
  end

  def teardown
    ActiveRecord::Base.send(:attribute_method_matchers).clear
    ActiveRecord::Base.send(:attribute_method_matchers).concat(@old_matchers)
  end

  def test_undeclared_attribute_method_does_not_affect_respond_to_and_method_missing
    topic = @target.new(:title => 'Budget')
    assert topic.respond_to?('title')
    assert_equal 'Budget', topic.title
    assert !topic.respond_to?('title_hello_world')
    assert_raise(NoMethodError) { topic.title_hello_world }
  end

  def test_declared_prefixed_attribute_method_affects_respond_to_and_method_missing
    topic = @target.new(:title => 'Budget')
    %w(default_ title_).each do |prefix|
      @target.class_eval "def #{prefix}attribute(*args) args end"
      @target.attribute_method_prefix prefix

      meth = "#{prefix}title"
      assert topic.respond_to?(meth)
      assert_equal ['title'], topic.send(meth)
      assert_equal ['title', 'a'], topic.send(meth, 'a')
      assert_equal ['title', 1, 2, 3], topic.send(meth, 1, 2, 3)
    end
  end

  def test_declared_suffixed_attribute_method_affects_respond_to_and_method_missing
    topic = @target.new(:title => 'Budget')
    %w(_default _title_default _it! _candidate= able?).each do |suffix|
      @target.class_eval "def attribute#{suffix}(*args) args end"
      @target.attribute_method_suffix suffix

      meth = "title#{suffix}"
      assert topic.respond_to?(meth)
      assert_equal ['title'], topic.send(meth)
      assert_equal ['title', 'a'], topic.send(meth, 'a')
      assert_equal ['title', 1, 2, 3], topic.send(meth, 1, 2, 3)
    end
  end

  def test_declared_affixed_attribute_method_affects_respond_to_and_method_missing
    topic = @target.new(:title => 'Budget')
    [['mark_', '_for_update'], ['reset_', '!'], ['default_', '_value?']].each do |prefix, suffix|
      @target.class_eval "def #{prefix}attribute#{suffix}(*args) args end"
      @target.attribute_method_affix({ :prefix => prefix, :suffix => suffix })

      meth = "#{prefix}title#{suffix}"
      assert topic.respond_to?(meth)
      assert_equal ['title'], topic.send(meth)
      assert_equal ['title', 'a'], topic.send(meth, 'a')
      assert_equal ['title', 1, 2, 3], topic.send(meth, 1, 2, 3)
    end
  end

  def test_should_unserialize_attributes_for_frozen_records
    myobj = {:value1 => :value2}
    topic = Topic.create("content" => myobj)
    topic.freeze
    assert_equal myobj, topic.content
  end

  def test_typecast_attribute_from_select_to_false
    topic = Topic.create(:title => 'Budget')
    topic = Topic.find(:first, :select => "topics.*, 1=2 as is_test")
    assert !topic.is_test?
  end

  def test_typecast_attribute_from_select_to_true
    topic = Topic.create(:title => 'Budget')
    topic = Topic.find(:first, :select => "topics.*, 2=2 as is_test")
    assert topic.is_test?
  end

  def test_kernel_methods_not_implemented_in_activerecord
    %w(test name display y).each do |method|
      assert !ActiveRecord::Base.instance_method_already_implemented?(method), "##{method} is defined"
    end
  end

  def test_defined_kernel_methods_implemented_in_model
    %w(test name display y).each do |method|
      klass = Class.new ActiveRecord::Base
      klass.class_eval "def #{method}() 'defined #{method}' end"
      assert klass.instance_method_already_implemented?(method), "##{method} is not defined"
    end
  end

  def test_defined_kernel_methods_implemented_in_model_abstract_subclass
    %w(test name display y).each do |method|
      abstract = Class.new ActiveRecord::Base
      abstract.class_eval "def #{method}() 'defined #{method}' end"
      abstract.abstract_class = true
      klass = Class.new abstract
      assert klass.instance_method_already_implemented?(method), "##{method} is not defined"
    end
  end

  def test_raises_dangerous_attribute_error_when_defining_activerecord_method_in_model
    %w(save create_or_update).each do |method|
      klass = Class.new ActiveRecord::Base
      klass.class_eval "def #{method}() 'defined #{method}' end"
      assert_raise ActiveRecord::DangerousAttributeError do
        klass.instance_method_already_implemented?(method)
      end
    end
  end

  def test_only_time_related_columns_are_meant_to_be_cached_by_default
    expected = %w(datetime timestamp time date).sort
    assert_equal expected, ActiveRecord::Base.attribute_types_cached_by_default.map(&:to_s).sort
  end

  def test_declaring_attributes_as_cached_adds_them_to_the_attributes_cached_by_default
    default_attributes = Topic.cached_attributes
    Topic.cache_attributes :replies_count
    expected = default_attributes + ["replies_count"]
    assert_equal expected.sort, Topic.cached_attributes.sort
    Topic.instance_variable_set "@cached_attributes", nil
  end

  def test_time_related_columns_are_actually_cached
    column_types = %w(datetime timestamp time date).map(&:to_sym)
    column_names = Topic.columns.select{|c| column_types.include?(c.type) }.map(&:name)

    assert_equal column_names.sort, Topic.cached_attributes.sort
    assert_equal time_related_columns_on_topic.sort, Topic.cached_attributes.sort
  end

  def test_accessing_cached_attributes_caches_the_converted_values_and_nothing_else
    t = topics(:first)
    cache = t.instance_variable_get "@attributes_cache"

    assert_not_nil cache
    assert cache.empty?

    all_columns = Topic.columns.map(&:name)
    cached_columns = time_related_columns_on_topic
    uncached_columns =  all_columns - cached_columns

    all_columns.each do |attr_name|
      attribute_gets_cached = Topic.cache_attribute?(attr_name)
      val = t.send attr_name unless attr_name == "type"
      if attribute_gets_cached
        assert cached_columns.include?(attr_name)
        assert_equal val, cache[attr_name]
      else
        assert uncached_columns.include?(attr_name)
        assert !cache.include?(attr_name)
      end
    end
  end

  def test_time_attributes_are_retrieved_in_current_time_zone
    in_time_zone "Pacific Time (US & Canada)" do
      utc_time = Time.utc(2008, 1, 1)
      record   = @target.new
      record[:written_on] = utc_time
      assert_equal utc_time, record.written_on # record.written on is equal to (i.e., simultaneous with) utc_time
      assert_kind_of ActiveSupport::TimeWithZone, record.written_on # but is a TimeWithZone
      assert_equal ActiveSupport::TimeZone["Pacific Time (US & Canada)"], record.written_on.time_zone # and is in the current Time.zone
      assert_equal Time.utc(2007, 12, 31, 16), record.written_on.time # and represents time values adjusted accordingly
    end
  end

  def test_setting_time_zone_aware_attribute_to_utc
    in_time_zone "Pacific Time (US & Canada)" do
      utc_time = Time.utc(2008, 1, 1)
      record   = @target.new
      record.written_on = utc_time
      assert_equal utc_time, record.written_on
      assert_equal ActiveSupport::TimeZone["Pacific Time (US & Canada)"], record.written_on.time_zone
      assert_equal Time.utc(2007, 12, 31, 16), record.written_on.time
    end
  end

  def test_setting_time_zone_aware_attribute_in_other_time_zone
    utc_time = Time.utc(2008, 1, 1)
    cst_time = utc_time.in_time_zone("Central Time (US & Canada)")
    in_time_zone "Pacific Time (US & Canada)" do
      record   = @target.new
      record.written_on = cst_time
      assert_equal utc_time, record.written_on
      assert_equal ActiveSupport::TimeZone["Pacific Time (US & Canada)"], record.written_on.time_zone
      assert_equal Time.utc(2007, 12, 31, 16), record.written_on.time
    end
  end

  def test_setting_time_zone_aware_attribute_with_string
    utc_time = Time.utc(2008, 1, 1)
    (-11..13).each do |timezone_offset|
      time_string = utc_time.in_time_zone(timezone_offset).to_s
      in_time_zone "Pacific Time (US & Canada)" do
        record   = @target.new
        record.written_on = time_string
        assert_equal Time.zone.parse(time_string), record.written_on
        assert_equal ActiveSupport::TimeZone["Pacific Time (US & Canada)"], record.written_on.time_zone
        assert_equal Time.utc(2007, 12, 31, 16), record.written_on.time
      end
    end
  end

  def test_setting_time_zone_aware_attribute_to_blank_string_returns_nil
    in_time_zone "Pacific Time (US & Canada)" do
      record   = @target.new
      record.written_on = ' '
      assert_nil record.written_on
    end
  end

  def test_setting_time_zone_aware_attribute_interprets_time_zone_unaware_string_in_time_zone
    time_string = 'Tue Jan 01 00:00:00 2008'
    (-11..13).each do |timezone_offset|
      in_time_zone timezone_offset do
        record   = @target.new
        record.written_on = time_string
        assert_equal Time.zone.parse(time_string), record.written_on
        assert_equal ActiveSupport::TimeZone[timezone_offset], record.written_on.time_zone
        assert_equal Time.utc(2008, 1, 1), record.written_on.time
      end
    end
  end

  def test_setting_time_zone_aware_attribute_in_current_time_zone
    utc_time = Time.utc(2008, 1, 1)
    in_time_zone "Pacific Time (US & Canada)" do
      record   = @target.new
      record.written_on = utc_time.in_time_zone
      assert_equal utc_time, record.written_on
      assert_equal ActiveSupport::TimeZone["Pacific Time (US & Canada)"], record.written_on.time_zone
      assert_equal Time.utc(2007, 12, 31, 16), record.written_on.time
    end
  end

  def test_setting_time_zone_conversion_for_attributes_should_write_value_on_class_variable
    Topic.skip_time_zone_conversion_for_attributes = [:field_a]
    Minimalistic.skip_time_zone_conversion_for_attributes = [:field_b]
    
    assert_equal [:field_a], Topic.skip_time_zone_conversion_for_attributes 
    assert_equal [:field_b], Minimalistic.skip_time_zone_conversion_for_attributes 
  end

  def test_read_attributes_respect_access_control
    privatize("title")

    topic = @target.new(:title => "The pros and cons of programming naked.")
    assert !topic.respond_to?(:title)
    exception = assert_raise(NoMethodError) { topic.title }
    assert_equal "Attempt to call private method", exception.message
    assert_equal "I'm private", topic.send(:title)
  end

  def test_write_attributes_respect_access_control
    privatize("title=(value)")

    topic = @target.new
    assert !topic.respond_to?(:title=)
    exception = assert_raise(NoMethodError) { topic.title = "Pants"}
    assert_equal "Attempt to call private method", exception.message
    topic.send(:title=, "Very large pants")
  end

  def test_question_attributes_respect_access_control
    privatize("title?")

    topic = @target.new(:title => "Isaac Newton's pants")
    assert !topic.respond_to?(:title?)
    exception = assert_raise(NoMethodError) { topic.title? }
    assert_equal "Attempt to call private method", exception.message
    assert topic.send(:title?)
  end

  def test_bulk_update_respects_access_control
    privatize("title=(value)")

    assert_raise(ActiveRecord::UnknownAttributeError) { topic = @target.new(:title => "Rants about pants") }
    assert_raise(ActiveRecord::UnknownAttributeError) { @target.new.attributes = { :title => "Ants in pants" } }
  end

  def test_read_attribute_overwrites_private_method_not_considered_implemented
    # simulate a model with a db column that shares its name an inherited
    # private method (e.g. Object#system)
    #
    Object.class_eval do
      private
      def title; "private!"; end
    end
    assert !@target.instance_method_already_implemented?(:title)
    topic = @target.new
    assert_equal nil, topic.title

    Object.send(:undef_method, :title) # remove test method from object
  end


  private
  def time_related_columns_on_topic
    Topic.columns.select{|c| [:time, :date, :datetime, :timestamp].include?(c.type)}.map(&:name)
  end

  def in_time_zone(zone)
    old_zone  = Time.zone
    old_tz    = ActiveRecord::Base.time_zone_aware_attributes

    Time.zone = zone ? ActiveSupport::TimeZone[zone] : nil
    ActiveRecord::Base.time_zone_aware_attributes = !zone.nil?
    yield
  ensure
    Time.zone = old_zone
    ActiveRecord::Base.time_zone_aware_attributes = old_tz
  end

  def privatize(method_signature)
    @target.class_eval <<-private_method
      private
      def #{method_signature}
        "I'm private"
      end
    private_method
  end
end