Out-of-range Time calculations transparently overflow to DateTime. Closes #7706.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6305 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

3 files changed, 71 insertions, 24 deletions

diff --git a/activesupport/CHANGELOG b/activesupport/CHANGELOG
index 7ccf8c985c..dab56d1501 100644
--- a/activesupport/CHANGELOG
+++ b/activesupport/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Out-of-range Time calculations transparently overflow to DateTime.  #7706 [Geoff Buesing]
+
 * DateTime calculations analogous to the Date and Time extensions.  #7693 [Geoff Buesing]
 
 * Give DateTime correct .to_s implementations, lets it play nice with ActiveRecord quoting.  #7649 [Geoff Buesing]
diff --git a/activesupport/lib/active_support/core_ext/time/calculations.rb b/activesupport/lib/active_support/core_ext/time/calculations.rb
index 70a4768d13..1c2daf0606 100644
--- a/activesupport/lib/active_support/core_ext/time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/time/calculations.rb
@@ -5,7 +5,7 @@ module ActiveSupport #:nodoc:
       module Calculations
         def self.included(base) #:nodoc:
           base.extend(ClassMethods)
-          
+
           base.send(:alias_method, :plus_without_duration, :+)
           base.send(:alias_method, :+, :plus_with_duration)
           base.send(:alias_method, :minus_without_duration, :-)
@@ -26,30 +26,50 @@ module ActiveSupport #:nodoc:
               month % 2 == 0 ? 31 : 30
             end
           end
+
+          # Returns a new Time if requested year can be accomodated by Ruby's Time class
+          # (i.e., if year is within either 1970..2038 or 1902..2038, depending on system architecture);
+          # otherwise returns a DateTime
+          def time_with_datetime_fallback(utc_or_local, year, month=1, day=1, hour=0, min=0, sec=0, usec=0)
+            ::Time.send(utc_or_local, year, month, day, hour, min, sec, usec)
+          rescue
+            offset = if utc_or_local.to_sym == :utc then 0 else ::DateTime.now.offset end
+            ::DateTime.civil(year, month, day, hour, min, sec, offset, 0)
+          end
+
+          # wraps class method time_with_datetime_fallback with utc_or_local == :utc
+          def utc_time(*args)
+            time_with_datetime_fallback(:utc, *args)
+          end
+
+          # wraps class method time_with_datetime_fallback with utc_or_local == :local
+          def local_time(*args)
+            time_with_datetime_fallback(:local, *args)
+          end
         end
 
         # Seconds since midnight: Time.now.seconds_since_midnight
         def seconds_since_midnight
           self.to_i - self.change(:hour => 0).to_i + (self.usec/1.0e+6)
         end
-            
+
         # Returns a new Time where one or more of the elements have been changed according to the +options+ parameter. The time options
-        # (hour, minute, sec, usec) reset cascadingly, so if only the hour is passed, then minute, sec, and usec is set to 0. If the hour and 
+        # (hour, minute, sec, usec) reset cascadingly, so if only the hour is passed, then minute, sec, and usec is set to 0. If the hour and
         # minute is passed, then sec and usec is set to 0.
         def change(options)
           ::Time.send(
-            self.utc? ? :utc : :local, 
-            options[:year]  || self.year, 
-            options[:month] || self.month, 
-            options[:mday]  || self.mday, 
-            options[:hour]  || self.hour, 
+            self.utc? ? :utc_time : :local_time,
+            options[:year]  || self.year,
+            options[:month] || self.month,
+            options[:mday]  || self.mday,
+            options[:hour]  || self.hour,
             options[:min]   || (options[:hour] ? 0 : self.min),
             options[:sec]   || ((options[:hour] || options[:min]) ? 0 : self.sec),
             options[:usec]  || ((options[:hour] || options[:min] || options[:sec]) ? 0 : self.usec)
           )
         end
-        
-        # Uses Date to provide precise Time calculations for years, months, and days.  The +options+ parameter takes a hash with 
+
+        # Uses Date to provide precise Time calculations for years, months, and days.  The +options+ parameter takes a hash with
         # any of these keys: :months, :days, :years.
         def advance(options)
           d = ::Date.new(year + (options.delete(:years) || 0), month, day)
@@ -64,7 +84,7 @@ module ActiveSupport #:nodoc:
           self.since(-seconds)
         end
 
-        # Returns a new Time representing the time a number of seconds since the instance time, this is basically a wrapper around 
+        # Returns a new Time representing the time a number of seconds since the instance time, this is basically a wrapper around
         #the Numeric extension. Do not use this method in combination with x.months, use months_since instead!
         def since(seconds)
           initial_dst = self.dst? ? 1 : 0
@@ -106,7 +126,7 @@ module ActiveSupport #:nodoc:
         def years_ago(years)
           change(:year => self.year - years)
         end
-        
+
         def years_since(years)
           change(:year => self.year + years)
         end
@@ -115,7 +135,7 @@ module ActiveSupport #:nodoc:
         def last_year
           years_ago(1)
         end
-        
+
         # Short-hand for years_since(1)
         def next_year
           years_since(1)
@@ -131,7 +151,7 @@ module ActiveSupport #:nodoc:
         def next_month
           months_since(1)
         end
-        
+
         # Returns a new Time representing the "start" of this week (Monday, 0:00)
         def beginning_of_week
           days_to_monday = self.wday!=0 ? self.wday-1 : 6
@@ -139,13 +159,13 @@ module ActiveSupport #:nodoc:
         end
         alias :monday :beginning_of_week
         alias :at_beginning_of_week :beginning_of_week
-        
+
         # Returns a new Time representing the start of the given day in next week (default is Monday).
         def next_week(day = :monday)
           days_into_week = { :monday => 0, :tuesday => 1, :wednesday => 2, :thursday => 3, :friday => 4, :saturday => 5, :sunday => 6}
           since(1.week).beginning_of_week.since(days_into_week[day].day).change(:hour => 0)
         end
-        
+
         # Returns a new Time representing the start of the day (0:00)
         def beginning_of_day
           (self - self.seconds_since_midnight).change(:usec => 0)
@@ -153,19 +173,19 @@ module ActiveSupport #:nodoc:
         alias :midnight :beginning_of_day
         alias :at_midnight :beginning_of_day
         alias :at_beginning_of_day :beginning_of_day
-        
+
         # Returns a new Time representing the end of the day (23:59:59)
         def end_of_day
           change(:hour => 23, :min => 59, :sec => 59)
         end
-        
+
         # Returns a new Time representing the start of the month (1st of the month, 0:00)
         def beginning_of_month
           #self - ((self.mday-1).days + self.seconds_since_midnight)
           change(:mday => 1,:hour => 0, :min => 0, :sec => 0, :usec => 0)
         end
         alias :at_beginning_of_month :beginning_of_month
-        
+
         # Returns a new Time representing the end of the month (last day of the month, 0:00)
         def end_of_month
           #self - ((self.mday-1).days + self.seconds_since_midnight)
@@ -173,29 +193,29 @@ module ActiveSupport #:nodoc:
           change(:mday => last_day,:hour => 0, :min => 0, :sec => 0, :usec => 0)
         end
         alias :at_end_of_month :end_of_month
-		  
+		
         # Returns  a new Time representing the start of the quarter (1st of january, april, july, october, 0:00)
         def beginning_of_quarter
           beginning_of_month.change(:month => [10, 7, 4, 1].detect { |m| m <= self.month })
         end
         alias :at_beginning_of_quarter :beginning_of_quarter
-        
+
         # Returns  a new Time representing the start of the year (1st of january, 0:00)
         def beginning_of_year
           change(:month => 1,:mday => 1,:hour => 0, :min => 0, :sec => 0, :usec => 0)
         end
         alias :at_beginning_of_year :beginning_of_year
-        
+
         # Convenience method which returns a new Time representing the time 1 day ago
         def yesterday
           self.ago(1.day)
         end
-        
+
         # Convenience method which returns a new Time representing the time 1 day since the instance time
         def tomorrow
           self.since(1.day)
         end
-        
+
         def plus_with_duration(other) #:nodoc:
           if ActiveSupport::Duration === other
             other.since(self)
diff --git a/activesupport/test/core_ext/time_ext_test.rb b/activesupport/test/core_ext/time_ext_test.rb
index 8d14be38c1..ebeaf264a4 100644
--- a/activesupport/test/core_ext/time_ext_test.rb
+++ b/activesupport/test/core_ext/time_ext_test.rb
@@ -314,6 +314,31 @@ class TimeExtCalculationsTest < Test::Unit::TestCase
     assert_equal 31, Time.days_in_month(12, 2005)
   end
 
+  def test_time_with_datetime_fallback
+    assert_equal Time.time_with_datetime_fallback(:utc, 2005, 2, 21, 17, 44, 30), Time.utc(2005, 2, 21, 17, 44, 30)
+    assert_equal Time.time_with_datetime_fallback(:local, 2005, 2, 21, 17, 44, 30), Time.local(2005, 2, 21, 17, 44, 30)
+    assert_equal Time.time_with_datetime_fallback(:utc, 2039, 2, 21, 17, 44, 30), DateTime.civil(2039, 2, 21, 17, 44, 30, 0, 0)
+    assert_equal Time.time_with_datetime_fallback(:local, 2039, 2, 21, 17, 44, 30), DateTime.civil(2039, 2, 21, 17, 44, 30, DateTime.now.offset, 0)
+    assert_equal Time.time_with_datetime_fallback(:utc, 1900, 2, 21, 17, 44, 30), DateTime.civil(1900, 2, 21, 17, 44, 30, 0, 0)
+    assert_equal Time.time_with_datetime_fallback(:local, 1900, 2, 21, 17, 44, 30), DateTime.civil(1900, 2, 21, 17, 44, 30, DateTime.now.offset, 0)
+    assert_equal Time.time_with_datetime_fallback(:utc, 2005), Time.utc(2005)
+    assert_equal Time.time_with_datetime_fallback(:utc, 2039), DateTime.civil(2039, 1, 1, 0, 0, 0, 0, 0)
+    assert_equal Time.time_with_datetime_fallback(:utc, 2005, 2, 21, 17, 44, 30, 1), Time.utc(2005, 2, 21, 17, 44, 30, 1) #with usec
+    assert_equal Time.time_with_datetime_fallback(:utc, 2039, 2, 21, 17, 44, 30, 1), DateTime.civil(2039, 2, 21, 17, 44, 30, 0, 0)
+  end
+
+  def test_utc_time
+    assert_equal Time.utc_time(2005, 2, 21, 17, 44, 30), Time.utc(2005, 2, 21, 17, 44, 30)
+    assert_equal Time.utc_time(2039, 2, 21, 17, 44, 30), DateTime.civil(2039, 2, 21, 17, 44, 30, 0, 0)
+    assert_equal Time.utc_time(1901, 2, 21, 17, 44, 30), DateTime.civil(1901, 2, 21, 17, 44, 30, 0, 0)
+  end
+
+  def test_local_time
+    assert_equal Time.local_time(2005, 2, 21, 17, 44, 30), Time.local(2005, 2, 21, 17, 44, 30)
+    assert_equal Time.local_time(2039, 2, 21, 17, 44, 30), DateTime.civil(2039, 2, 21, 17, 44, 30, DateTime.now.offset, 0)
+    assert_equal Time.local_time(1901, 2, 21, 17, 44, 30), DateTime.civil(1901, 2, 21, 17, 44, 30, DateTime.now.offset, 0)
+  end
+
   def test_next_month_on_31st
     assert_equal Time.local(2005, 9, 30), Time.local(2005, 8, 31).next_month
   end