seems to be entering with nil key/value pairs

Causes a return of nil if the key is nil
(makes it work again, I honestly have next to no idea why)

lib/heap_dump/dumped_module.rb

@@ -36,6 +36,7 @@ def method_table
       def find_class(name)
         name = name.to_s
         constant_table.map do |key, val|
+          return nil if key.nil?
           return val.as_module if key.data == name
         end