2 files changed, 64 insertions, 12 deletions
diff --git a/activesupport/lib/active_support/core_ext/time/calculations.rb b/activesupport/lib/active_support/core_ext/time/calculations.rb
index c5fbbcf890..f3235d11bb 100644
--- a/activesupport/lib/active_support/core_ext/time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/time/calculations.rb
@@ -1,5 +1,6 @@
 require 'active_support/duration'
 require 'active_support/core_ext/time/zones'
+require 'active_support/core_ext/time/conversions'
 
 class Time
   COMMON_YEAR_DAYS_IN_MONTH = [nil, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
@@ -8,7 +9,7 @@ class Time
   class << self
     # Overriding case equality method so that it returns true for ActiveSupport::TimeWithZone instances
     def ===(other)
-      other.is_a?(::Time)
+      super || (self == Time && other.is_a?(ActiveSupport::TimeWithZone))
     end
 
     # Return the number of days in the given month.
@@ -160,27 +161,46 @@ class Time
     months_since(1)
   end
 
-  # Returns a new Time representing the "start" of this week (Monday, 0:00)
-  def beginning_of_week
-    days_to_monday = wday!=0 ? wday-1 : 6
-    (self - days_to_monday.days).midnight
+  # 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 Time representing the "start" of this week, week starts on start_day (default is :monday, i.e. Monday, 0:00).
+  def beginning_of_week(start_day = :monday)
+    days_to_start = days_to_week_start(start_day)
+    (self - days_to_start.days).midnight
   end
-  alias :monday :beginning_of_week
   alias :at_beginning_of_week :beginning_of_week
 
-  # Returns a new Time representing the end of this week, (end of Sunday)
-  def end_of_week
-    days_to_sunday = wday!=0 ? 7-wday : 0
-    (self + days_to_sunday.days).end_of_day
+  # Returns a new +Date+/+DateTime+ representing the start of this week. Week is
+  # assumed to start on a Monday. +DateTime+ objects have their time set to 0:00.
+  def monday
+    beginning_of_week
+  end
+
+  # Returns a new Time representing the end of this week, week starts on start_day (default is :monday, i.e. end of Sunday).
+  def end_of_week(start_day = :monday)
+    days_to_end =  6 - days_to_week_start(start_day)
+    (self + days_to_end.days).end_of_day
   end
   alias :at_end_of_week :end_of_week
 
-  # Returns a new Time representing the start of the given day in the previous week (default is Monday).
+  # Returns a new +Date+/+DateTime+ representing the end of this week. Week is
+  # assumed to start on a Monday. +DateTime+ objects have their time set to 23:59:59.
+  def sunday
+    end_of_week
+  end
+
+  # Returns a new Time representing the start of the given day in the previous week (default is :monday).
   def prev_week(day = :monday)
     ago(1.week).beginning_of_week.since(DAYS_INTO_WEEK[day].day).change(:hour => 0)
   end
 
-  # Returns a new Time representing the start of the given day in next week (default is Monday).
+  # Returns a new Time representing the start of the given day in next week (default is :monday).
   def next_week(day = :monday)
     since(1.week).beginning_of_week.since(DAYS_INTO_WEEK[day].day).change(:hour => 0)
   end
@@ -311,4 +331,14 @@ class Time
   end
   alias_method :compare_without_coercion, :<=>
   alias_method :<=>, :compare_with_coercion
+
+  # Layers additional behavior on Time#eql? so that ActiveSupport::TimeWithZone instances
+  # can be eql? to an equivalent Time
+  def eql_with_coercion(other)
+    # if other is an ActiveSupport::TimeWithZone, coerce a Time instance from it so we can do eql? comparison
+    other = other.comparable_time if other.respond_to?(:comparable_time)
+    eql_without_coercion(other)
+  end
+  alias_method :eql_without_coercion, :eql?
+  alias_method :eql?, :eql_with_coercion
 end
diff --git a/activesupport/lib/active_support/core_ext/time/conversions.rb b/activesupport/lib/active_support/core_ext/time/conversions.rb
index d9d5e02778..49ac18d245 100644
--- a/activesupport/lib/active_support/core_ext/time/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/time/conversions.rb
@@ -55,9 +55,31 @@ class Time
     utc? && alternate_utc_string || ActiveSupport::TimeZone.seconds_to_utc_offset(utc_offset, colon)
   end
 
+  # Converts a Time object to a Date, dropping hour, minute, and second precision.
+  #
+  #   my_time = Time.now  # => Mon Nov 12 22:59:51 -0500 2007
+  #   my_time.to_date     # => Mon, 12 Nov 2007
+  #
+  #   your_time = Time.parse("1/13/2009 1:13:03 P.M.")  # => Tue Jan 13 13:13:03 -0500 2009
+  #   your_time.to_date                                 # => Tue, 13 Jan 2009
+  def to_date
+    ::Date.new(year, month, day)
+  end unless method_defined?(:to_date)
+
   # A method to keep Time, Date and DateTime instances interchangeable on conversions.
   # In this case, it simply returns +self+.
   def to_time
     self
   end unless method_defined?(:to_time)
+
+  # Converts a Time instance to a Ruby DateTime instance, preserving UTC offset.
+  #
+  #   my_time = Time.now    # => Mon Nov 12 23:04:21 -0500 2007
+  #   my_time.to_datetime   # => Mon, 12 Nov 2007 23:04:21 -0500
+  #
+  #   your_time = Time.parse("1/13/2009 1:13:03 P.M.")  # => Tue Jan 13 13:13:03 -0500 2009
+  #   your_time.to_datetime                             # => Tue, 13 Jan 2009 13:13:03 -0500
+  def to_datetime
+    ::DateTime.civil(year, month, day, hour, min, sec, Rational(utc_offset, 86400))
+  end unless method_defined?(:to_datetime)
 end