1 files changed, 14 insertions, 6 deletions
diff --git a/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb b/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb
index 9e50fea3fc..5fb5953811 100644
--- a/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb
+++ b/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb
@@ -7,14 +7,22 @@ require 'action_dispatch/request/session'
 module ActionDispatch
   module Session
     class SessionRestoreError < StandardError #:nodoc:
-      attr_reader :original_exception
 
-      def initialize(const_error)
-        @original_exception = const_error
+      def initialize(const_error = nil)
+        if const_error
+          ActiveSupport::Deprecation.warn("Passing #original_exception is deprecated and has no effect. " \
+                                          "Exceptions will automatically capture the original exception.", caller)
+        end
 
         super("Session contains objects whose class definition isn't available.\n" +
           "Remember to require the classes for all objects kept in the session.\n" +
-          "(Original exception: #{const_error.message} [#{const_error.class}])\n")
+          "(Original exception: #{$!.message} [#{$!.class}])\n")
+        set_backtrace $!.backtrace
+      end
+
+      def original_exception
+        ActiveSupport::Deprecation.warn("#original_exception is deprecated. Use #cause instead.", caller)
+        cause
       end
     end
 
@@ -59,8 +67,8 @@ module ActionDispatch
           begin
             # Note that the regexp does not allow $1 to end with a ':'
             $1.constantize
-          rescue LoadError, NameError => e
-            raise ActionDispatch::Session::SessionRestoreError, e, e.backtrace
+          rescue LoadError, NameError
+            raise ActionDispatch::Session::SessionRestoreError
           end
           retry
         else