Adding Time and DateTime #formatted_offset, for outputting +HH:MM utc offset strings with cross-platform consistency

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@8698 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/CHANGELOG

@@ -1,5 +1,7 @@
 *SVN*
 
+* Adding Time and DateTime #formatted_offset, for outputting +HH:MM utc offset strings with cross-platform consistency [Geoff Buesing]
+
 * Adding alternate_utc_string option to TimeZone#formatted_offset. Removing unneeded TimeZone#offset. [Geoff Buesing]
 
 * Introduce ActiveSupport::TimeWithZone, for wrapping Time instances with a TimeZone. Introduce instance methods to Time for creating TimeWithZone instances, and class methods for managing a global time zone. [Geoff Buesing]

activesupport/lib/active_support/core_ext/date_time/conversions.rb

@@ -52,6 +52,15 @@ module ActiveSupport #:nodoc:
           end
         end
 
+        # Returns the utc_offset as an +HH:MM formatted string. Examples:
+        #
+        #   datetime = DateTime.civil(2000, 1, 1, 0, 0, 0, Rational(-6, 24))
+        #   datetime.formatted_offset         # => "-06:00"
+        #   datetime.formatted_offset(false)  # => "-0600"
+        def formatted_offset(colon = true, alternate_utc_string = nil)
+          utc? && alternate_utc_string || utc_offset.to_utc_offset_s(colon)
+        end
+        
         # Overrides the default inspect method with a human readable one, e.g., "Mon, 21 Feb 2005 14:30:00 +0000"
         def readable_inspect
           to_s(:rfc822)

activesupport/lib/active_support/core_ext/time/conversions.rb

@@ -55,6 +55,14 @@ module ActiveSupport #:nodoc:
             to_default_s
           end
         end
+        
+        # Returns the utc_offset as an +HH:MM formatted string. Examples:
+        #
+        #   Time.local(2000).formatted_offset         # => "-06:00"
+        #   Time.local(2000).formatted_offset(false)  # => "-0600"
+        def formatted_offset(colon = true, alternate_utc_string = nil)
+          utc? && alternate_utc_string || utc_offset.to_utc_offset_s(colon)
+        end
 
         # Convert a Time object to a Date, dropping hour, minute, and second precision.
         #

activesupport/lib/active_support/json/encoders/time.rb

@@ -1,5 +1,5 @@
 class Time
   def to_json(options = nil) #:nodoc:
-    %("#{strftime("%Y/%m/%d %H:%M:%S")} #{utc_offset.to_utc_offset_s(false)}")
+    %("#{strftime("%Y/%m/%d %H:%M:%S")} #{formatted_offset(false)}")
   end
 end

activesupport/test/core_ext/date_time_ext_test.rb

@@ -241,6 +241,18 @@ class DateTimeExtCalculationsTest < Test::Unit::TestCase
     assert_equal DateTime.civil(2005, 2, 21, 10, 11, 12, 0), DateTime.civil(2005, 2, 21, 10, 11, 12, 0).utc
     assert_equal DateTime.civil(2005, 2, 21, 9, 11, 12, 0), DateTime.civil(2005, 2, 21, 10, 11, 12, Rational(1, 24)).utc
   end
+  
+  def test_formatted_offset_with_utc
+    assert_equal '+00:00', DateTime.civil(2000).formatted_offset
+    assert_equal '+0000', DateTime.civil(2000).formatted_offset(false)
+    assert_equal 'UTC', DateTime.civil(2000).formatted_offset(true, 'UTC')
+  end
+  
+  def test_formatted_offset_with_local
+    dt = DateTime.civil(2005, 2, 21, 10, 11, 12, Rational(-5, 24))
+    assert_equal '-05:00', dt.formatted_offset
+    assert_equal '-0500', dt.formatted_offset(false)
+  end
 
   protected
     def with_timezone(new_tz = 'US/Eastern')

activesupport/test/core_ext/time_ext_test.rb

@@ -409,6 +409,21 @@ class TimeExtCalculationsTest < Test::Unit::TestCase
   def test_acts_like_time
     assert Time.new.acts_like_time?
   end
+  
+  def test_formatted_offset_with_utc
+    assert_equal '+00:00', Time.utc(2000).formatted_offset
+    assert_equal '+0000', Time.utc(2000).formatted_offset(false)
+    assert_equal 'UTC', Time.utc(2000).formatted_offset(true, 'UTC')
+  end
+  
+  def test_formatted_offset_with_local
+    with_timezone 'US/Eastern' do
+      assert_equal '-05:00', Time.local(2000).formatted_offset
+      assert_equal '-0500', Time.local(2000).formatted_offset(false)
+      assert_equal '-04:00', Time.local(2000, 7).formatted_offset
+      assert_equal '-0400', Time.local(2000, 7).formatted_offset(false)
+    end
+  end
 
   protected
     def with_timezone(new_tz = 'US/Eastern')