1 files changed, 7 insertions, 1 deletions
diff --git a/activesupport/lib/active_support/core_ext/date_time/calculations.rb b/activesupport/lib/active_support/core_ext/date_time/calculations.rb
index 0481bd2195..0ff36eeb6d 100644
--- a/activesupport/lib/active_support/core_ext/date_time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/calculations.rb
@@ -138,6 +138,12 @@ class DateTime
 
   # Layers additional behavior on DateTime#<=> so that Time and ActiveSupport::TimeWithZone instances can be compared with a DateTime
   def <=>(other)
-    super other.kind_of?(Infinity) ? other : other.to_datetime
+    if other.kind_of?(Infinity)
+      super
+    elsif other.respond_to? :to_datetime
+      super other.to_datetime
+    else
+      nil
+    end
   end
 end