problem in variant_decorator about RansackTranslator.new

[orbit-dna]

I'm using 3-0-stable, and found this:
in app/models/spree/variant_decorator.rb line: 6 :

translated_params = SpreeI18n::RansackTranslator.new(self, params).translated_params

while in app/models/spree_i18n/translatable.rb line: 15 :

translated_params = RansackTranslator.new(self, params || {}).translated_params

notice the missing || {} in app/models/spree/variant_decorator.rb.
This causes an exception: "undefined method `each_with_object' for nil:NilClass", when params is nil.
So, I'm not sure is it a bug or something else ?
or should I check params before pass it to Spree::Variant.ransack ?