Replace use of alias chains with prepend at core_ext/date

1 files changed, 36 insertions, 0 deletions

diff --git a/activesupport/lib/active_support/core_ext/time/operators.rb b/activesupport/lib/active_support/core_ext/time/operators.rb
new file mode 100644
index 0000000000..161304dcb3
--- /dev/null
+++ b/activesupport/lib/active_support/core_ext/time/operators.rb
@@ -0,0 +1,36 @@
+require 'active_support/core_ext/date_and_time/with_duration'
+
+module ActiveSupport
+  module TimeOperators # :nodoc:
+    include DateAndTime::WithDuration
+
+    # Layers additional behavior on Time#<=> so that DateTime and ActiveSupport::TimeWithZone instances
+    # can be chronologically compared with a Time
+    def <=>(other)
+      # we're avoiding Time#to_datetime and Time#to_time because they're expensive
+      if other.class == Time
+        super
+      elsif other.is_a?(Time)
+        super(other.to_time)
+      else
+        to_datetime <=> other
+      end
+    end
+
+    # Layers additional behavior on Time#eql? so that ActiveSupport::TimeWithZone instances
+    # can be eql? to an equivalent Time
+    def eql?(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)
+      super
+    end
+
+    # Time#- can also be used to determine the number of seconds between two Time instances.
+    # We're layering on additional behavior so that ActiveSupport::TimeWithZone instances
+    # are coerced into values that Time#- will recognize
+    def -(other)
+      other = other.comparable_time if other.respond_to?(:comparable_time)
+      other.is_a?(DateTime) ? to_f - other.to_f : super
+    end
+  end
+end