hence.rb in facets-2.5.0

- old
+ new

@@ -1,29 +1,30 @@
 require 'facets/time/set'
 
 class Time
 
-  if defined?(::ActiveSupport)
+  if defined?(::ActiveSupport) && method_defined?(:since)
 
     alias_method :in, :since
     alias_method :hence, :since
 
   else
 
     # Returns a new Time representing the time
     # a number of time-units ago.
     #
     def ago(number, units=:seconds)
-      time =(
+      return hence(-number, units) if number < 0
+
+      time = (
         case units.to_s.downcase.to_sym
         when :years
           set(:year => (year - number))
         when :months
-          #years = ((month - number) / 12).to_i
-          y = ((month - number) / 12).to_i
-          m = ((month - number - 1) % 12) + 1
-          set(:year => (year - y), :month => m)
+          new_month = ((month - number - 1) % 12) + 1
+          y = (number / 12) + (new_month > month ? 1 : 0)
+          set(:year => (year - y), :month => new_month)
         when :weeks
           self - (number * 604800)
         when :days
           self - (number * 86400)
         when :hours
@@ -41,18 +42,20 @@
     #
     # Returns a new Time representing the time
     # a number of time-units hence.
 
     def hence(number, units=:seconds)
-      time =(
+      return ago(-number, units) if number < 0
+
+      time = (
         case units.to_s.downcase.to_sym
         when :years
           set( :year=>(year + number) )
         when :months
-          y = ((month + number) / 12).to_i
-          m = ((month + number - 1) % 12) + 1
-          set(:year => (year + y), :month => m)
+          new_month = ((month + number - 1) % 12) + 1
+          y = (number / 12) + (new_month < month ? 1 : 0)
+          set(:year => (year + y), :month => new_month)
         when :weeks
           self + (number * 604800)
         when :days
           self + (number * 86400)
         when :hours
@@ -72,12 +75,12 @@
     alias_method :since, :hence
 
     # Adjust DST
     #
     # TODO: Can't seem to get this to pass ActiveSupport tests.
-    #       Even though it is essentially identical to the
-    #       ActiveSupport code (see Time#since in time/calculations.rb).
-    #       It handels all but 4 tests.
+    # Even though it is essentially identical to the
+    # ActiveSupport code (see Time#since in time/calculations.rb).
+    # It handles all but 4 tests.
     def dst_adjustment(time)
       self_dst = self.dst? ? 1 : 0
       time_dst = time.dst? ? 1 : 0
       seconds  = (self - time).abs
       if (seconds >= 86400 && self_dst != time_dst)