beginning_of_week extended in both Time and Date so that to return week start based on start day that is monday by default

1 files changed, 16 insertions, 8 deletions

diff --git a/activesupport/lib/active_support/core_ext/date/calculations.rb b/activesupport/lib/active_support/core_ext/date/calculations.rb
index c6d5f29690..a322075c4e 100644
--- a/activesupport/lib/active_support/core_ext/date/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date/calculations.rb
@@ -174,19 +174,27 @@ class Date
     months_since(1)
   end unless method_defined?(:next_month)
 
-  # Returns a new Date/DateTime representing the "start" of this week (i.e, Monday; DateTime objects will have time set to 0:00).
-  def beginning_of_week
-    days_to_monday = self.wday!=0 ? self.wday-1 : 6
-    result = self - days_to_monday
+  # Returns number of days to start of this week, week starts on start_day (default is Monday)
+  def days_to_week_start(start_day = :monday)
+    start_day_number = DAYS_INTO_WEEK[start_day]
+    current_day_number = wday != 0 ? wday - 1 : 6
+    days_span = current_day_number - start_day_number
+    days_span >= 0 ? days_span : 7 + days_span
+  end
+
+  # Returns a new Date/DateTime representing the "start" of this week, week starts on start_day (i.e, Monday; DateTime objects will have time set to 0:00).
+  def beginning_of_week(start_day = :monday)
+    days_to_start = days_to_week_start(start_day)
+    result = self - days_to_start
     self.acts_like?(:time) ? result.midnight : result
   end
   alias :monday :beginning_of_week
   alias :at_beginning_of_week :beginning_of_week
 
-  # Returns a new Date/DateTime representing the end of this week (Sunday, DateTime objects will have time set to 23:59:59).
-  def end_of_week
-    days_to_sunday = self.wday!=0 ? 7-self.wday : 0
-    result = self + days_to_sunday.days
+  # Returns a new Date/DateTime representing the end of this week, week starts on start_day (Sunday, DateTime objects will have time set to 23:59:59).
+  def end_of_week(start_day = :monday)
+    days_to_end = 6 - days_to_week_start(start_day)
+    result = self + days_to_end.days
     self.acts_like?(:time) ? result.end_of_day : result
   end
   alias :sunday :end_of_week