Add #on_weekend?, #next_weekday, and #prev_weekday methods to Date, Time, and DateTime

`#on_weekend?` returns true if the receiving date/time falls on a Saturday or
Sunday.

`#next_weekday` returns a new date/time representing the next day that does
not fall on a Saturday or Sunday.

`#prev_weekday` returns a new date/time representing the previous day that
does not fall on a Saturday or Sunday.

1 files changed, 25 insertions, 0 deletions

diff --git a/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb b/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb
index b85e49aca5..4e86b270f9 100644
--- a/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date_and_time/calculations.rb
@@ -9,6 +9,7 @@ module DateAndTime
       :saturday  => 5,
       :sunday    => 6
     }
+    WEEKEND_DAYS = [ 6, 0 ]
 
     # Returns a new date/time representing yesterday.
     def yesterday
@@ -35,6 +36,11 @@ module DateAndTime
       self > self.class.current
     end
 
+    # Returns true if the date/time falls on a Saturday or Sunday.
+    def on_weekend?
+      wday.in?(WEEKEND_DAYS)
+    end
+
     # Returns a new date/time the specified number of days ago.
     def days_ago(days)
       advance(:days => -days)
@@ -116,6 +122,15 @@ module DateAndTime
       first_hour(weeks_since(1).beginning_of_week.days_since(days_span(given_day_in_next_week)))
     end
 
+    # Returns a new date/time representing the next weekday.
+    def next_weekday
+      if tomorrow.on_weekend?
+        next_week(:monday).change(hour: hour, min: min, sec: sec, usec: try(:usec))
+      else
+        tomorrow
+      end
+    end
+
     # Short-hand for months_since(1).
     def next_month
       months_since(1)
@@ -140,6 +155,16 @@ module DateAndTime
     end
     alias_method :last_week, :prev_week
 
+    # Returns a new date/time representing the previous weekday.
+    def prev_weekday
+      if yesterday.on_weekend?
+        beginning_of_week(:friday).change(hour: hour, min: min, sec: sec, usec: try(:usec))
+      else
+        yesterday
+      end
+    end
+    alias_method :last_weekday, :prev_weekday
+
     # Short-hand for months_ago(1).
     def prev_month
       months_ago(1)