Add Time Zone support to ActiveRecord, and config.time_zone property for specifying a default Time Zone. Closes #10982 [Geoff Buesing, rick]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@8806 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

5 files changed, 163 insertions, 8 deletions

diff --git a/activerecord/CHANGELOG b/activerecord/CHANGELOG
index b2e2a117fb..1fd8cbd722 100644
--- a/activerecord/CHANGELOG
+++ b/activerecord/CHANGELOG
@@ -1,5 +1,9 @@
 *SVN*
 
+* Add timezone-aware attribute readers and writers. #10982 [Geoff Buesing]
+
+* Instantiating time objects in multiparameter attributes uses Time.zone if available.  #10982 [rick]
+
 * Add note about how ActiveRecord::Observer classes are initialized in a Rails app. #10980 [fxn]
 
 * MySQL: omit text/blob defaults from the schema instead of using an empty string.  #10963 [mdeiters]
diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb
index 657c575866..f976e70a06 100644
--- a/activerecord/lib/active_record/attribute_methods.rb
+++ b/activerecord/lib/active_record/attribute_methods.rb
@@ -8,6 +8,10 @@ module ActiveRecord
       base.attribute_method_suffix(*DEFAULT_SUFFIXES)
       base.cattr_accessor :attribute_types_cached_by_default, :instance_writer => false
       base.attribute_types_cached_by_default = ATTRIBUTE_TYPES_CACHED_BY_DEFAULT
+      base.cattr_accessor :time_zone_aware_attributes, :instance_writer => false
+      base.time_zone_aware_attributes = false
+      base.cattr_accessor :skip_time_zone_conversion_for_attributes, :instance_writer => false
+      base.skip_time_zone_conversion_for_attributes = []
     end
 
     # Declare and check for suffixed attribute methods.
@@ -64,13 +68,19 @@ module ActiveRecord
           unless instance_method_already_implemented?(name)
             if self.serialized_attributes[name]
               define_read_method_for_serialized_attribute(name)
+            elsif create_time_zone_conversion_attribute?(name, column)
+              define_read_method_for_time_zone_conversion(name)
             else
               define_read_method(name.to_sym, name, column)
             end
           end
 
           unless instance_method_already_implemented?("#{name}=")
-            define_write_method(name.to_sym)
+            if create_time_zone_conversion_attribute?(name, column)
+              define_write_method_for_time_zone_conversion(name)
+            else  
+              define_write_method(name.to_sym)
+            end
           end
 
           unless instance_method_already_implemented?("#{name}?")
@@ -121,6 +131,10 @@ module ActiveRecord
           @@attribute_method_suffixes ||= []
         end
         
+        def create_time_zone_conversion_attribute?(name, column)
+          time_zone_aware_attributes && !skip_time_zone_conversion_for_attributes.include?(name.to_sym) && [:datetime, :timestamp].include?(column.type)
+        end
+        
         # Define an attribute reader method.  Cope with nil column.
         def define_read_method(symbol, attr_name, column)
           cast_code = column.type_cast_code('v') if column
@@ -140,6 +154,18 @@ module ActiveRecord
         def define_read_method_for_serialized_attribute(attr_name)
           evaluate_attribute_method attr_name, "def #{attr_name}; unserialize_attribute('#{attr_name}'); end"
         end
+        
+        def define_read_method_for_time_zone_conversion(attr_name)
+          method_body = <<-EOV
+            def #{attr_name}(reload = false)
+              cached = @attributes_cache['#{attr_name}']
+              return cached if cached && !reload
+              time = read_attribute('#{attr_name}')
+              @attributes_cache['#{attr_name}'] = time.acts_like?(:time) ? time.in_current_time_zone : time
+            end
+          EOV
+          evaluate_attribute_method attr_name, method_body
+        end
 
         # Define an attribute ? method.
         def define_question_method(attr_name)
@@ -149,6 +175,19 @@ module ActiveRecord
         def define_write_method(attr_name)
           evaluate_attribute_method attr_name, "def #{attr_name}=(new_value);write_attribute('#{attr_name}', new_value);end", "#{attr_name}="
         end
+        
+        def define_write_method_for_time_zone_conversion(attr_name)
+          method_body = <<-EOV
+            def #{attr_name}=(time)
+              if time
+                time = time.to_time rescue time unless time.acts_like?(:time)
+                time = time.in_current_time_zone if time.acts_like?(:time)
+              end
+              write_attribute(:#{attr_name}, time)
+            end
+          EOV
+          evaluate_attribute_method attr_name, method_body, "#{attr_name}="
+        end
 
         # Evaluate the definition for an attribute related method
         def evaluate_attribute_method(attr_name, method_definition, method_name=attr_name)
@@ -303,7 +342,6 @@ module ActiveRecord
       end
       super
     end
-    
 
     private
     
diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index f1759aa68f..d1729b6ff4 100755
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -2470,8 +2470,12 @@ module ActiveRecord #:nodoc:
       end
 
       # Includes an ugly hack for Time.local instead of Time.new because the latter is reserved by Time itself.
-      def instantiate_time_object(*values)
-        @@default_timezone == :utc ? Time.utc(*values) : Time.local(*values)
+      def instantiate_time_object(name, values)
+        if Time.zone && !self.class.skip_time_zone_conversion_for_attributes.include?(name.to_sym)
+          Time.zone.new(*values)
+        else
+          @@default_timezone == :utc ? Time.utc(*values) : Time.local(*values)
+        end
       end
 
       def execute_callstack_for_multiparameter_attributes(callstack)
@@ -2483,12 +2487,12 @@ module ActiveRecord #:nodoc:
           else
             begin
               value = if Time == klass
-                instantiate_time_object(*values)
+                instantiate_time_object(name, values)
               elsif Date == klass
                 begin
                   Date.new(*values)
                 rescue ArgumentError => ex # if Date.new raises an exception on an invalid date
-                  instantiate_time_object(*values).to_date # we instantiate Time object and convert it back to a date thus using Time's logic in handling invalid dates
+                  instantiate_time_object(name, values).to_date # we instantiate Time object and convert it back to a date thus using Time's logic in handling invalid dates
                 end
               else
                 klass.new(*values)
diff --git a/activerecord/test/cases/attribute_methods_test.rb b/activerecord/test/cases/attribute_methods_test.rb
index d2bfb02846..427c14edbd 100755
--- a/activerecord/test/cases/attribute_methods_test.rb
+++ b/activerecord/test/cases/attribute_methods_test.rb
@@ -14,7 +14,6 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     ActiveRecord::Base.attribute_method_suffix *@old_suffixes
   end
 
-
   def test_match_attribute_method_query_returns_match_data
     assert_not_nil md = @target.match_attribute_method?('title=')
     assert_equal 'title', md.pre_match
@@ -97,7 +96,7 @@ class AttributeMethodsTest < ActiveRecord::TestCase
   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
+  end
 
   def test_declaring_attributes_as_cached_adds_them_to_the_attributes_cached_by_default
     default_attributes = Topic.cached_attributes
@@ -138,9 +137,67 @@ end
       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 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 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 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_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_current_time_zone
+      assert_equal utc_time, record.written_on
+      assert_equal TimeZone["Pacific Time (US & Canada)"], record.written_on.time_zone
+      assert_equal Time.utc(2007, 12, 31, 16), record.written_on.time
+    end
+  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 ? 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
 end
diff --git a/activerecord/test/cases/base_test.rb b/activerecord/test/cases/base_test.rb
index 04ed751eb5..bd076888e1 100755
--- a/activerecord/test/cases/base_test.rb
+++ b/activerecord/test/cases/base_test.rb
@@ -924,6 +924,58 @@ class BasicsTest < ActiveRecord::TestCase
     assert_equal Time.local(2004, 6, 24, 16, 24, 0), topic.written_on
   end
 
+  def test_multiparameter_attributes_on_time_with_utc
+    ActiveRecord::Base.default_timezone = :utc
+    attributes = {
+      "written_on(1i)" => "2004", "written_on(2i)" => "6", "written_on(3i)" => "24",
+      "written_on(4i)" => "16", "written_on(5i)" => "24", "written_on(6i)" => "00"
+    }
+    topic = Topic.find(1)
+    topic.attributes = attributes
+    assert_equal Time.utc(2004, 6, 24, 16, 24, 0), topic.written_on
+  ensure
+    ActiveRecord::Base.default_timezone = :local
+  end
+
+  def test_multiparameter_attributes_on_time_with_time_zone_aware_attributes
+    ActiveRecord::Base.time_zone_aware_attributes = true
+    ActiveRecord::Base.default_timezone = :utc
+    Time.zone = TimeZone[-28800]
+    attributes = {
+      "written_on(1i)" => "2004", "written_on(2i)" => "6", "written_on(3i)" => "24",
+      "written_on(4i)" => "16", "written_on(5i)" => "24", "written_on(6i)" => "00"
+    }
+    topic = Topic.find(1)
+    topic.attributes = attributes
+    assert_equal Time.utc(2004, 6, 24, 23, 24, 0), topic.written_on
+    assert_equal Time.utc(2004, 6, 24, 16, 24, 0), topic.written_on.time
+    assert_equal Time.zone, topic.written_on.time_zone
+  ensure
+    ActiveRecord::Base.time_zone_aware_attributes = false
+    ActiveRecord::Base.default_timezone = :local
+    Time.zone = nil
+  end
+  
+  def test_multiparameter_attributes_on_time_with_skip_time_zone_conversion_for_attributes
+    ActiveRecord::Base.time_zone_aware_attributes = true
+    ActiveRecord::Base.default_timezone = :utc
+    Time.zone = TimeZone[-28800]
+    Topic.skip_time_zone_conversion_for_attributes = [:written_on]
+    attributes = {
+      "written_on(1i)" => "2004", "written_on(2i)" => "6", "written_on(3i)" => "24",
+      "written_on(4i)" => "16", "written_on(5i)" => "24", "written_on(6i)" => "00"
+    }
+    topic = Topic.find(1)
+    topic.attributes = attributes
+    assert_equal Time.utc(2004, 6, 24, 16, 24, 0), topic.written_on
+    assert_equal false, topic.written_on.respond_to?(:time_zone)
+  ensure
+    ActiveRecord::Base.time_zone_aware_attributes = false
+    ActiveRecord::Base.default_timezone = :local
+    Time.zone = nil
+    Topic.skip_time_zone_conversion_for_attributes = []
+  end
+
   def test_multiparameter_attributes_on_time_with_empty_seconds
     attributes = {
       "written_on(1i)" => "2004", "written_on(2i)" => "6", "written_on(3i)" => "24",