http/request: make sure we start tls when using a https proxy

http/request.lua

@@ -459,6 +459,7 @@ function request_methods:go(timeout)
 				end
 				host = assert(proxy.host, "proxy is missing host")
 				port = proxy.port or http_util.scheme_to_port[proxy.scheme]
+				tls = (proxy.scheme == "https")
 				use_absolute_target = true
 				if proxy.userinfo then
 					if not cloned_headers then

spec/request_spec.lua

@@ -630,6 +630,31 @@ describe("http.request module", function()
 				stream:shutdown()
 			end)
 		end)
+		it("works with a tls proxy server", function()
+			test(function(stream)
+				local h = assert(stream:get_headers())
+				assert.truthy(stream:checktls()) -- came in via TLS
+				local _, host, port = stream:localname()
+				local authority = http_util.to_authority(host, port, "http")
+				assert.same("http", h:get(":scheme"))
+				assert.same(authority, h:get ":authority")
+				assert.same("/", h:get(":path"))
+				local resp_headers = new_headers()
+				resp_headers:append(":status", "200")
+				assert(stream:write_headers(resp_headers, false))
+				assert(stream:write_chunk("hello world", true))
+			end, function(req)
+				req.proxy = {
+					scheme = "https";
+					host = req.host;
+					port = req.port;
+				}
+				local headers, stream = assert(req:go())
+				assert.same("200", headers:get(":status"))
+				assert.same("hello world", assert(stream:get_body_as_string()))
+				stream:shutdown()
+			end)
+		end)
 		it("works with a proxy server with a path component", function()
 			test(function(stream)
 				local h = assert(stream:get_headers())