added test for trailer headers (http/1 only)

lib/httpx/connection/http1.rb

@@ -117,7 +117,7 @@ module HTTPX
       response = @request.response
       log(level: 2) { "trailer headers received" }
 
-      log(color: :yellow) { h.each.map { |f, v| "-> HEADER: #{f}: #{v}" }.join("\n") }
+      log(color: :yellow) { h.each.map { |f, v| "-> HEADER: #{f}: #{v.join(", ")}" }.join("\n") }
       response.merge_headers(h)
     end
 

sig/connection/http1.rbs

@@ -31,7 +31,7 @@ module HTTPX
 
     def on_headers: (Hash[String, Array[String]] headers) -> void
 
-    def on_trailers: (Array[String, String] headers) -> void
+    def on_trailers: (Hash[String, Array[String]] headers) -> void
 
     def on_data: (string chunk) -> void
 

test/http_test.rb

@@ -64,6 +64,24 @@ class HTTPTest < Minitest::Test
     end
   end
 
+  def test_trailers
+    server = HTTPTrailersServer.new
+    th = Thread.new { server.start }
+    begin
+      uri = "#{server.origin}/"
+      HTTPX.plugin(SessionWithPool).wrap do |http|
+        response = http.get(uri)
+        assert response.to_s == "trailers", "expected trailers endpoint"
+        verify_header(response.headers, "trailer", "x-trailer,x-trailer-2")
+        verify_header(response.headers, "x-trailer", "hello")
+        verify_header(response.headers, "x-trailer-2", "world")
+      end
+    ensure
+      server.shutdown
+      th.join
+    end
+  end
+
   private
 
   def origin(orig = httpbin)

test/support/keep_alive_server.rb

@@ -101,3 +101,37 @@ class NoContentLengthServer < TestServer
     mount("/", NoContentLengthApp)
   end
 end
+
+class HTTPTrailersServer < TestServer
+  module Trailers
+    def self.extended(obj)
+      super
+
+      obj.singleton_class.class_eval do
+        alias_method(:send_body_without_trailers, :send_body)
+        alias_method(:send_body, :send_body_with_trailers)
+      end
+    end
+
+    def send_body_with_trailers(socket)
+      send_body_without_trailers(socket)
+
+      socket.write(+"x-trailer: hello" << "\r\n")
+      socket.write(+"x-trailer-2: world" << "\r\n" << "\r\n")
+    end
+  end
+
+  class HTTPTrailersApp < WEBrick::HTTPServlet::AbstractServlet
+    def do_GET(_req, res) # rubocop:disable Naming/MethodName
+      res.status = 200
+      res["trailer"] = "x-trailer,x-trailer-2"
+      res.body = "trailers"
+      res.extend(Trailers)
+    end
+  end
+
+  def initialize(options = {})
+    super
+    mount("/", HTTPTrailersApp)
+  end
+end