Don't wrap request bodies if they are already Readables (#38)

We don't need to wrap request bodies if they already conform to the `::Protocol::HTTP::Body::Readable` interface. This way developers can use other kinds of `Readable`s directly when making calls with `Faraday`.

Author: jakeonfire

lib/async/http/faraday/adapter.rb

@@ -153,9 +153,11 @@ def call(env)
 						end
 
 						if body = env.body
-							# We need to wrap the body in a Readable object so that it can be read in chunks:
+							# We need to ensure the body is wrapped in a Readable object so that it can be read in chunks:
 							# Faraday's body only responds to `#read`.
-							if body.respond_to?(:read)
+							if body.is_a?(::Protocol::HTTP::Body::Readable)
+								# Good to go
+							elsif body.respond_to?(:read)
 								body = BodyReadWrapper.new(body)
 							else
 								body = ::Protocol::HTTP::Body::Buffered.wrap(body)

test/async/http/faraday/adapter.rb

@@ -15,6 +15,8 @@
 require 'faraday'
 require 'faraday/multipart'
 
+require 'protocol/http/body/file'
+
 describe Async::HTTP::Faraday::Adapter do
 	def get_response(url = bound_url, path = '/index', adapter_options: {})
 		connection = Faraday.new(url) do |builder|
@@ -125,6 +127,16 @@ def get_response(url = bound_url, path = '/index', adapter_options: {})
 
 				expect(response.body).to be == 'text=Hello+World'
 			end
+
+			it "can use a ::Protocol::HTTP::Body::Readable body" do
+				readable = ::Protocol::HTTP::Body::File.new(File.open(__FILE__, 'r'), 0...128)
+
+				response = Faraday.new do |builder|
+					builder.adapter :async_http
+				end.post(bound_url, readable)
+
+				expect(response.body).to be == File.read(__FILE__, 128)
+			end
 		end
 	end