class RuboCop::Cop::ThreadSafety::MutableClassInstanceVariable

def frozen_string_literal?(node)
  literal_types = if target_ruby_version >= 3.0
                    FROZEN_STRING_LITERAL_TYPES_RUBY30
                  else
                    FROZEN_STRING_LITERAL_TYPES_RUBY27
                  end
  literal_types.include?(node.type) && frozen_string_literals_enabled?
end