Added partial days support to `DateTime`'s `advance` method.

You can now add partial days (e.g. 2.5.days) to `DateTime` with the advance method.
This was acheived by mimicing the `advance` implementation in `Time`.

1 files changed, 15 insertions, 5 deletions

diff --git a/activesupport/lib/active_support/core_ext/date_time/calculations.rb b/activesupport/lib/active_support/core_ext/date_time/calculations.rb
index 8e5d723074..2d33a86466 100644
--- a/activesupport/lib/active_support/core_ext/date_time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/calculations.rb
@@ -53,17 +53,27 @@ class DateTime
   # <tt>:months</tt>, <tt>:weeks</tt>, <tt>:days</tt>, <tt>:hours</tt>,
   # <tt>:minutes</tt>, <tt>:seconds</tt>.
   def advance(options)
+    unless options[:weeks].nil?
+      options[:weeks], partial_weeks = options[:weeks].divmod(1)
+      options[:days] = options.fetch(:days, 0) + 7 * partial_weeks
+    end
+
+    unless options[:days].nil?
+      options[:days], partial_days = options[:days].divmod(1)
+      options[:hours] = options.fetch(:hours, 0) + 24 * partial_days
+    end
+
     d = to_date.advance(options)
-    datetime_advanced_by_date = change(:year => d.year, :month => d.month, :day => d.day)
+    time_advanced_by_date = change(:year => d.year, :month => d.month, :day => d.day)
     seconds_to_advance = \
       options.fetch(:seconds, 0) +
-      options.fetch(:minutes, 0) * 60 +
-      options.fetch(:hours, 0) * 3600
+        options.fetch(:minutes, 0) * 60 +
+        options.fetch(:hours, 0) * 3600
 
     if seconds_to_advance.zero?
-      datetime_advanced_by_date
+      time_advanced_by_date
     else
-      datetime_advanced_by_date.since seconds_to_advance
+      time_advanced_by_date.since(seconds_to_advance)
     end
   end