use supertest and assert port

test/app.listen.js

@@ -2,27 +2,10 @@
 
 var net = require('net')
 var express = require('../')
-var http = require('http');
 var assert = require('assert');
+var request = require('supertest')
 
 describe('app.listen()', function(){
-  function makeGetRequest(port, cb){
-    http
-      .get('http://localhost:' + port, function(res){
-        var data = ''
-        res.on('data', function(chunk){
-          data += chunk;
-        });
-
-        res.on('end', function(){
-          cb(null, data);
-        });
-      })
-      .on('error', function(error) {
-        cb(error, null);
-      });
-  }
-
   it('should wrap with an HTTP server', function(done){
     var app = express();
 
@@ -33,32 +16,27 @@ describe('app.listen()', function(){
   })
 
   it('should listen on the requested port', function (done) {
-    var expectedResponseBody = 'hello world';
-    var server;
     var app = express()
-      .get('/', function(req, res){
-        res.send(expectedResponseBody);
-      });
 
-    getPort(function (openPortError, port) {
-      if(openPortError !== null) {
-        return done(openPortError);
-      }
+    app.get('/', function (req, res) {
+      res.json({ port: req.socket.address().port })
+    })
+
+    getPort(function (error, port) {
+      if (error) return done(error)
 
-      server = app.listen(port, function(){
-        makeGetRequest(port, function(getError, responseBody) {
-          try {
-            assert.strictEqual(getError, null);
-            assert.strictEqual(responseBody, expectedResponseBody)
-            done()
-          } catch (error) {
-            done(error);
-          } finally {
-            server.close();
-          }
-        });
-      });
-    });
+      assert.strictEqual(typeof port, 'number')
+
+      var server = app.listen(port, function () {
+        request(server)
+          .get('/')
+          .expect(200, { port: port }, function (error) {
+            server.close(function () {
+              done(error)
+            })
+          })
+      })
+    })
   })
 })