Cache conditionally or just yield the block uncached

conditionally_cache.rb

  def conditionally_cache(key, args = {}, &block)
    positive, negative = args[:if], args[:unless]
    fail "Must supply at most one of :if or :unless" if positive && negative

    if (positive && positive.call(key)) || (negative && !negative.call(key))
      Rails.logger.debug "BENCH: cache hit, #{key.cache_key}"
      cache(key, &block)
    else
      Rails.logger.debug "BENCH: NOT cache hit, #{key.cache_key}"
      yield
    end
    ""
  end