You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: json.rb
    path of file: ./repos/faraday/lib/faraday/request
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require 'json'

module Faraday
  class Request
    # Request middleware that encodes the body as JSON.
    #
    # Processes only requests with matching Content-type or those without a type.
    # If a request doesn't have a
    
      def body?(env)
        body = env[:body]
        case body
        when true, false
          true
        when nil
          # NOTE: nil can be converted to `"null"`, but this middleware doesn't process `nil` for the compatibility.
          false
        else
          !(body.respond_to?(:to_str) && body.empty?)
        end
      end