From d2bb4862d20d581f6f5511e1ebc3f9a1c821fbf6 Mon Sep 17 00:00:00 2001
From: garygsc <garygsc@gmail.com>
Date: Fri, 25 Oct 2019 17:04:26 -0600
Subject: [PATCH 1/3] doc: use arrow functions in writing-tests.md

---
 doc/guides/writing-tests.md | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/doc/guides/writing-tests.md b/doc/guides/writing-tests.md
index 584b1d2373ce1b..460a0cd221191b 100644
--- a/doc/guides/writing-tests.md
+++ b/doc/guides/writing-tests.md
@@ -163,7 +163,7 @@ const http = require('http');
 
 let request = 0;
 let response = 0;
-process.on('exit', function() {
+process.on('exit', () => {
   assert.equal(request, 1, 'http server "request" callback was not called');
   assert.equal(response, 1, 'http request "response" callback was not called');
 });
@@ -171,10 +171,10 @@ process.on('exit', function() {
 const server = http.createServer((req, res) => {
   request++;
   res.end();
-}).listen(0, function() {
+}).listen(0, () => {
   const options = {
     agent: null,
-    port: this.address().port
+    port: server.address().port
   };
   http.get(options, (res) => {
     response++;
@@ -193,10 +193,10 @@ const http = require('http');
 
 const server = http.createServer(common.mustCall((req, res) => {
   res.end();
-})).listen(0, function() {
+})).listen(0, () => {
   const options = {
     agent: null,
-    port: this.address().port
+    port: server.address().port
   };
   http.get(options, common.mustCall((res) => {
     res.resume();
@@ -216,7 +216,7 @@ shutting down an HTTP server after a specific number of requests).
 ```javascript
 const Countdown = require('../common/countdown');
 
-const countdown = new Countdown(2, function() {
+const countdown = new Countdown(2, () => {
   console.log('.');
 });
 

From f57926fc6d9a4cc0a854652c615d2d55dd997d40 Mon Sep 17 00:00:00 2001
From: garygsc <garygsc@gmail.com>
Date: Fri, 25 Oct 2019 17:19:01 -0600
Subject: [PATCH 2/3] doc: sync example in writing-tests.md

Match test/parallel/test-http-agent-null.js
---
 doc/guides/writing-tests.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/doc/guides/writing-tests.md b/doc/guides/writing-tests.md
index 460a0cd221191b..9e65821db34599 100644
--- a/doc/guides/writing-tests.md
+++ b/doc/guides/writing-tests.md
@@ -193,7 +193,7 @@ const http = require('http');
 
 const server = http.createServer(common.mustCall((req, res) => {
   res.end();
-})).listen(0, () => {
+})).listen(0, common.mustCall(() => {
   const options = {
     agent: null,
     port: server.address().port
@@ -202,7 +202,7 @@ const server = http.createServer(common.mustCall((req, res) => {
     res.resume();
     server.close();
   }));
-});
+}));
 
 ```
 

From e2e095af68268527d2e2bccf5809aeb86c9d2e21 Mon Sep 17 00:00:00 2001
From: garygsc <garygsc@gmail.com>
Date: Fri, 25 Oct 2019 17:45:09 -0600
Subject: [PATCH 3/3] doc: match functionality in writing-tests.md example

---
 doc/guides/writing-tests.md | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/doc/guides/writing-tests.md b/doc/guides/writing-tests.md
index 9e65821db34599..7022bf8f938f78 100644
--- a/doc/guides/writing-tests.md
+++ b/doc/guides/writing-tests.md
@@ -162,9 +162,11 @@ const assert = require('assert');
 const http = require('http');
 
 let request = 0;
+let listening = 0;
 let response = 0;
 process.on('exit', () => {
   assert.equal(request, 1, 'http server "request" callback was not called');
+  assert.equal(listening, 1, 'http server "listening" callback was not called');
   assert.equal(response, 1, 'http request "response" callback was not called');
 });
 
@@ -172,6 +174,7 @@ const server = http.createServer((req, res) => {
   request++;
   res.end();
 }).listen(0, () => {
+  listening++;
   const options = {
     agent: null,
     port: server.address().port