Date.beginning_of_week thread local and beginning_of_week application config option added (default is Monday)

4 files changed, 69 insertions, 17 deletions

diff --git a/activesupport/lib/active_support/core_ext/date/calculations.rb b/activesupport/lib/active_support/core_ext/date/calculations.rb
index 86badf4d29..ee23bc578c 100644
--- a/activesupport/lib/active_support/core_ext/date/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date/calculations.rb
@@ -9,6 +9,29 @@ class Date
   include DateAndTime::Calculations
 
   class << self
+    attr_accessor :beginning_of_week_default
+
+    # Returns the week start (e.g. :monday) for the current request, if this has been set (via Date.beginning_of_week=).
+    # If <tt>Date.beginning_of_week</tt> has not been set for the current request, returns the week start specified in <tt>config.beginning_of_week</tt>.
+    # If no config.beginning_of_week was specified, returns :monday.
+    def beginning_of_week
+      Thread.current[:beginning_of_week] || beginning_of_week_default || :monday
+    end
+
+    # Sets <tt>Date.beginning_of_week</tt> to a week start (e.g. :monday) for current request/thread.
+    #
+    # This method accepts any of the following day symbols:
+    # :monday, :tuesday, :wednesday, :thursday, :friday, :saturday, :sunday
+    def beginning_of_week=(week_start)
+      Thread.current[:beginning_of_week] = find_beginning_of_week!(week_start)
+    end
+
+    # Returns week start day symbol (e.g. :monday), or raises an ArgumentError for invalid day symbol.
+    def find_beginning_of_week!(week_start)
+      raise ArgumentError, "Invalid beginning of week: #{week_start}" unless ::Date::DAYS_INTO_WEEK.keys.include?(week_start)
+      week_start
+    end
+
     # Returns a new Date representing the date 1 day ago (i.e. yesterday's date).
     def yesterday
       ::Date.current.yesterday
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 e703fca7a7..1f78b9eb5a 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
@@ -109,10 +109,11 @@ module DateAndTime
     alias :at_beginning_of_year :beginning_of_year
 
     # Returns a new date/time representing the given day in the next week.
-    # Default is :monday.
+    # Week is assumed to start on +start_day+, default is
+    # +Date.beginning_of_week+ or +config.beginning_of_week+ when set.
     # DateTime objects have their time set to 0:00.
-    def next_week(day = :monday)
-      first_hour{ weeks_since(1).beginning_of_week.days_since(DAYS_INTO_WEEK[day]) }
+    def next_week(start_day = Date.beginning_of_week)
+      first_hour{ weeks_since(1).beginning_of_week.days_since(days_span(start_day)) }
     end
 
     # Short-hand for months_since(1).
@@ -131,10 +132,11 @@ module DateAndTime
     end
 
     # Returns a new date/time representing the given day in the previous week.
-    # Default is :monday.
+    # Week is assumed to start on +start_day+, default is
+    # +Date.beginning_of_week+ or +config.beginning_of_week+ when set.
     # DateTime objects have their time set to 0:00.
-    def prev_week(day = :monday)
-      first_hour{ weeks_ago(1).beginning_of_week.days_since(DAYS_INTO_WEEK[day]) }
+    def prev_week(start_day = Date.beginning_of_week)
+      first_hour{ weeks_ago(1).beginning_of_week.days_since(days_span(start_day)) }
     end
     alias_method :last_week, :prev_week
 
@@ -157,31 +159,44 @@ module DateAndTime
     alias_method :last_year, :prev_year
 
     # Returns the number of days to the start of the week on the given day.
-    # Default is :monday.
-    def days_to_week_start(start_day = :monday)
+    # Week is assumed to start on +start_day+, default is
+    # +Date.beginning_of_week+ or +config.beginning_of_week+ when set.
+    def days_to_week_start(start_day = Date.beginning_of_week)
       start_day_number = DAYS_INTO_WEEK[start_day]
       current_day_number = wday != 0 ? wday - 1 : 6
       (current_day_number - start_day_number) % 7
     end
 
     # Returns a new date/time representing the start of this week on the given day.
-    # Default is :monday.
-    # DateTime objects have their time set to 0:00.
-    def beginning_of_week(start_day = :monday)
+    # Week is assumed to start on +start_day+, default is
+    # +Date.beginning_of_week+ or +config.beginning_of_week+ when set.
+    # +DateTime+ objects have their time set to 0:00.
+    def beginning_of_week(start_day = Date.beginning_of_week)
       result = days_ago(days_to_week_start(start_day))
       acts_like?(:time) ? result.midnight : result
     end
     alias :at_beginning_of_week :beginning_of_week
-    alias :monday :beginning_of_week
+
+    # Returns Monday of this week assuming that week starts on Monday.
+    # +DateTime+ objects have their time set to 0:00.
+    def monday
+      beginning_of_week(:monday)
+    end
 
     # Returns a new date/time representing the end of this week on the given day.
-    # Default is :monday (i.e end of Sunday).
+    # Week is assumed to start on +start_day+, default is
+    # +Date.beginning_of_week+ or +config.beginning_of_week+ when set.
     # DateTime objects have their time set to 23:59:59.
-    def end_of_week(start_day = :monday)
+    def end_of_week(start_day = Date.beginning_of_week)
       last_hour{ days_since(6 - days_to_week_start(start_day)) }
     end
     alias :at_end_of_week :end_of_week
-    alias :sunday :end_of_week
+
+    # Returns Sunday of this week assuming that week starts on Monday.
+    # +DateTime+ objects have their time set to 23:59:59.
+    def sunday
+      end_of_week(:monday)
+    end
 
     # Returns a new date/time representing the end of the month.
     # DateTime objects will have a time set to 23:59:59.
@@ -209,5 +224,9 @@ module DateAndTime
       result = yield
       acts_like?(:time) ? result.end_of_day : result
     end
+
+    def days_span(day)
+      (DAYS_INTO_WEEK[day] - DAYS_INTO_WEEK[Date.beginning_of_week]) % 7
+    end
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/time/calculations.rb b/activesupport/lib/active_support/core_ext/time/calculations.rb
index 148f2c27f1..78baa80ccd 100644
--- a/activesupport/lib/active_support/core_ext/time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/time/calculations.rb
@@ -169,8 +169,9 @@ class Time
     beginning_of_day..end_of_day
   end
 
-  # Returns a Range representing the whole week of the current time. Week starts on start_day (default is :monday, i.e. end of Sunday).
-  def all_week(start_day = :monday)
+  # Returns a Range representing the whole week of the current time.
+  # Week starts on start_day, default is <tt>Date.week_start</tt> or <tt>config.week_start</tt> when set.
+  def all_week(start_day = Date.beginning_of_week)
     beginning_of_week(start_day)..end_of_week(start_day)
   end
 
diff --git a/activesupport/lib/active_support/railtie.rb b/activesupport/lib/active_support/railtie.rb
index aa8d408da9..29351db742 100644
--- a/activesupport/lib/active_support/railtie.rb
+++ b/activesupport/lib/active_support/railtie.rb
@@ -27,6 +27,15 @@ module ActiveSupport
       Time.zone_default = zone_default
     end
 
+    # Sets the default week start
+    # If assigned value is not a valid day symbol (e.g. :sunday, :monday, ...), an exception will be raised.
+    initializer "active_support.initialize_beginning_of_week" do |app|
+      require 'active_support/core_ext/date/calculations'
+      beginning_of_week_default = Date.find_beginning_of_week!(app.config.beginning_of_week)
+
+      Date.beginning_of_week_default = beginning_of_week_default
+    end
+
     initializer "active_support.set_configs" do |app|
       app.config.active_support.each do |k, v|
         k = "#{k}="