1 files changed, 35 insertions, 0 deletions
diff --git a/actionpack/lib/action_dispatch/request/utils.rb b/actionpack/lib/action_dispatch/request/utils.rb
new file mode 100644
index 0000000000..9d4f1aa3c5
--- /dev/null
+++ b/actionpack/lib/action_dispatch/request/utils.rb
@@ -0,0 +1,35 @@
+module ActionDispatch
+  class Request < Rack::Request
+    class Utils # :nodoc:
+
+      mattr_accessor :perform_deep_munge
+      self.perform_deep_munge = true
+
+      class << self
+        # Remove nils from the params hash
+        def deep_munge(hash, keys = [])
+          return hash unless perform_deep_munge
+
+          hash.each do |k, v|
+            keys << k
+            case v
+            when Array
+              v.grep(Hash) { |x| deep_munge(x, keys) }
+              v.compact!
+              if v.empty?
+                hash[k] = nil
+                ActiveSupport::Notifications.instrument("deep_munge.action_controller", keys: keys)
+              end
+            when Hash
+              deep_munge(v, keys)
+            end
+            keys.pop
+          end
+
+          hash
+        end
+      end
+    end
+  end
+end
+