2 files changed, 13 insertions, 8 deletions
diff --git a/actionpack/lib/action_controller/metal/exceptions.rb b/actionpack/lib/action_controller/metal/exceptions.rb
index 5260dc0336..5c0ada37be 100644
--- a/actionpack/lib/action_controller/metal/exceptions.rb
+++ b/actionpack/lib/action_controller/metal/exceptions.rb
@@ -3,12 +3,19 @@ module ActionController
   end
 
   class BadRequest < ActionControllerError #:nodoc:
-    attr_reader :original_exception
-
     def initialize(msg = nil, e = nil)
+      if e
+        ActiveSupport::Deprecation.warn("Passing #original_exception is deprecated and has no effect. " \
+                                        "Exceptions will automatically capture the original exception.", caller)
+      end
+
       super(msg)
-      @original_exception = e
-      set_backtrace e.backtrace if e
+      set_backtrace $!.backtrace if $!
+    end
+
+    def original_exception
+      ActiveSupport::Deprecation.warn("#original_exception is deprecated. Use #cause instead.", caller)
+      cause
     end
   end
 
diff --git a/actionpack/lib/action_controller/metal/rescue.rb b/actionpack/lib/action_controller/metal/rescue.rb
index 68cc9a9c9b..81b9a7b9ed 100644
--- a/actionpack/lib/action_controller/metal/rescue.rb
+++ b/actionpack/lib/action_controller/metal/rescue.rb
@@ -7,10 +7,8 @@ module ActionController #:nodoc:
     include ActiveSupport::Rescuable
 
     def rescue_with_handler(exception)
-      if (exception.respond_to?(:original_exception) &&
-          (orig_exception = exception.original_exception) &&
-          handler_for_rescue(orig_exception))
-        exception = orig_exception
+      if exception.cause && handler_for_rescue(exception.cause)
+        exception = exception.cause
       end
       super(exception)
     end