test: wrap countdown callback in common.mustCall

This adds a implicit common.mustCall to the callback provided to
the countdown.

PR-URL: #18506
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: Bamieh

test/common/README.md

@@ -388,7 +388,7 @@ Synchronous version of `spawnPwd`.
 The `Countdown` module provides a simple countdown mechanism for tests that
 require a particular action to be taken after a given number of completed
 tasks (for instance, shutting down an HTTP server after a specific number of
-requests).
+requests). The Countdown will fail the test if the remainder did not reach 0.
 
 <!-- eslint-disable strict, required-modules -->
 ```js

test/common/countdown.js

@@ -4,13 +4,14 @@
 const assert = require('assert');
 const kLimit = Symbol('limit');
 const kCallback = Symbol('callback');
+const common = require('./');
 
 class Countdown {
   constructor(limit, cb) {
     assert.strictEqual(typeof limit, 'number');
     assert.strictEqual(typeof cb, 'function');
     this[kLimit] = limit;
-    this[kCallback] = cb;
+    this[kCallback] = common.mustCall(cb);
   }
 
   dec() {

test/fixtures/failcounter.js

@@ -0,0 +1,2 @@
+const Countdown = require('../common/countdown');
+new Countdown(2, () => {});

test/parallel/test-common-countdown.js

@@ -3,13 +3,31 @@
 const common = require('../common');
 const assert = require('assert');
 const Countdown = require('../common/countdown');
+const fixtures = require('../common/fixtures');
+const { execFile } = require('child_process');
 
 let done = '';
-
-const countdown = new Countdown(2, common.mustCall(() => done = true));
+const countdown = new Countdown(2, () => done = true);
 assert.strictEqual(countdown.remaining, 2);
 countdown.dec();
 assert.strictEqual(countdown.remaining, 1);
 countdown.dec();
 assert.strictEqual(countdown.remaining, 0);
 assert.strictEqual(done, true);
+
+const failFixtures = [
+  [
+    fixtures.path('failcounter.js'),
+    'Mismatched <anonymous> function calls. Expected exactly 1, actual 0.',
+  ]
+];
+
+for (const p of failFixtures) {
+  const [file, expected] = p;
+  execFile(process.argv[0], [file], common.mustCall((ex, stdout, stderr) => {
+    assert.ok(ex);
+    assert.strictEqual(stderr, '');
+    const firstLine = stdout.split('\n').shift();
+    assert.strictEqual(firstLine, expected);
+  }));
+}

test/parallel/test-http-after-connect.js

@@ -32,7 +32,7 @@ const server = http.createServer(common.mustCall((req, res) => {
   setTimeout(() => res.end(req.url), 50);
 }, 2));
 
-const countdown = new Countdown(2, common.mustCall(() => server.close()));
+const countdown = new Countdown(2, () => server.close());
 
 server.on('connect', common.mustCall((req, socket) => {
   socket.write('HTTP/1.1 200 Connection established\r\n\r\n');

test/parallel/test-http-agent-destroyed-socket.js

@@ -80,7 +80,7 @@ const server = http.createServer(common.mustCall((req, res) => {
     assert(request1.socket.destroyed);
     // assert not reusing the same socket, since it was destroyed.
     assert.notStrictEqual(request1.socket, request2.socket);
-    const countdown = new Countdown(2, common.mustCall(() => server.close()));
+    const countdown = new Countdown(2, () => server.close());
     request2.socket.on('close', common.mustCall(() => countdown.dec()));
     response.on('end', common.mustCall(() => countdown.dec()));
     response.resume();

test/parallel/test-http-agent-maxsockets-regress-4050.js

@@ -17,7 +17,7 @@ const server = http.createServer(common.mustCall((req, res) => {
   res.end('hello world');
 }, 6));
 
-const countdown = new Countdown(6, common.mustCall(() => server.close()));
+const countdown = new Countdown(6, () => server.close());
 
 function get(path, callback) {
   return http.get({

test/parallel/test-http-agent-maxsockets.js

@@ -26,13 +26,13 @@ function get(path, callback) {
   }, callback);
 }
 
-const countdown = new Countdown(2, common.mustCall(() => {
+const countdown = new Countdown(2, () => {
   const freepool = agent.freeSockets[Object.keys(agent.freeSockets)[0]];
   assert.strictEqual(freepool.length, 2,
                      `expect keep 2 free sockets, but got ${freepool.length}`);
   agent.destroy();
   server.close();
-}));
+});
 
 function dec() {
   process.nextTick(() => countdown.dec());

test/parallel/test-http-client-abort.js

@@ -26,7 +26,7 @@ const Countdown = require('../common/countdown');
 
 const N = 8;
 
-const countdown = new Countdown(N, common.mustCall(() => server.close()));
+const countdown = new Countdown(N, () => server.close());
 
 const server = http.Server(common.mustCall((req, res) => {
   res.writeHead(200);
@@ -37,9 +37,9 @@ const server = http.Server(common.mustCall((req, res) => {
 server.listen(0, common.mustCall(() => {
 
   const requests = [];
-  const reqCountdown = new Countdown(N, common.mustCall(() => {
+  const reqCountdown = new Countdown(N, () => {
     requests.forEach((req) => req.abort());
-  }));
+  });
 
   const options = { port: server.address().port };
 

test/parallel/test-http-client-parse-error.js

@@ -25,7 +25,7 @@ const http = require('http');
 const net = require('net');
 const Countdown = require('../common/countdown');
 
-const countdown = new Countdown(2, common.mustCall(() => server.close()));
+const countdown = new Countdown(2, () => server.close());
 
 const payloads = [
   'HTTP/1.1 302 Object Moved\r\nContent-Length: 0\r\n\r\nhi world',