test: refactor/cleanup a number of cluster tests

* Move shared code into common
* Favor use of strictEqual
* Add some missing common.mustCalls
* Other general cleanup

PR-URL: https://github.com/nodejs/node/pull/8261
Reviewed-By: Santiago Gimeno <santiago.gimeno@gmail.com>

1 files changed, 29 insertions, 48 deletions

diff --git a/test/parallel/test-cluster-worker-exit.js b/test/parallel/test-cluster-worker-exit.js
index ad1e30ddb0..1c0ec509c4 100644
--- a/test/parallel/test-cluster-worker-exit.js
+++ b/test/parallel/test-cluster-worker-exit.js
@@ -6,24 +6,24 @@
 // - the worker.exitedAfterDisconnect flag, and worker.state are correct
 // - the worker process actually goes away
 
-var common = require('../common');
-var assert = require('assert');
-var cluster = require('cluster');
+const common = require('../common');
+const assert = require('assert');
+const cluster = require('cluster');
 
-var EXIT_CODE = 42;
+const EXIT_CODE = 42;
 
 if (cluster.isWorker) {
-  var http = require('http');
-  var server = http.Server(function() { });
+  const http = require('http');
+  const server = http.Server(() => { });
 
-  server.once('listening', function() {
+  server.once('listening', common.mustCall(() => {
     process.exit(EXIT_CODE);
-  });
+  }));
   server.listen(common.PORT, '127.0.0.1');
 
 } else if (cluster.isMaster) {
 
-  var expected_results = {
+  const expected_results = {
     cluster_emitDisconnect: [1, "the cluster did not emit 'disconnect'"],
     cluster_emitExit: [1, "the cluster did not emit 'exit'"],
     cluster_exitCode: [EXIT_CODE, 'the cluster exited w/ incorrect exitCode'],
@@ -38,7 +38,7 @@ if (cluster.isWorker) {
     worker_exitCode: [EXIT_CODE, 'the worker exited w/ incorrect exitCode'],
     worker_signalCode: [null, 'the worker exited w/ incorrect signalCode']
   };
-  var results = {
+  const results = {
     cluster_emitDisconnect: 0,
     cluster_emitExit: 0,
     worker_emitDisconnect: 0,
@@ -47,51 +47,45 @@ if (cluster.isWorker) {
 
 
   // start worker
-  var worker = cluster.fork();
-
-  worker.once('listening', function() {
-    // the worker is up and running...
-  });
-
+  const worker = cluster.fork();
 
   // Check cluster events
-  cluster.on('disconnect', function() {
+  cluster.on('disconnect', common.mustCall(() => {
     results.cluster_emitDisconnect += 1;
-  });
-  cluster.on('exit', function(worker) {
+  }));
+  cluster.on('exit', common.mustCall((worker) => {
     results.cluster_exitCode = worker.process.exitCode;
     results.cluster_signalCode = worker.process.signalCode;
     results.cluster_emitExit += 1;
-  });
+  }));
 
   // Check worker events and properties
-  worker.on('disconnect', function() {
+  worker.on('disconnect', common.mustCall(() => {
     results.worker_emitDisconnect += 1;
     results.worker_suicideMode = worker.suicide;
     results.worker_exitedAfterDisconnect = worker.exitedAfterDisconnect;
     results.worker_state = worker.state;
     if (results.worker_emitExit > 0) {
-      process.nextTick(function() { finish_test(); });
+      process.nextTick(() => finish_test());
     }
-  });
+  }));
 
   // Check that the worker died
-  worker.once('exit', function(exitCode, signalCode) {
+  worker.once('exit', common.mustCall((exitCode, signalCode) => {
     results.worker_exitCode = exitCode;
     results.worker_signalCode = signalCode;
     results.worker_emitExit += 1;
-    results.worker_died = !alive(worker.process.pid);
+    results.worker_died = !common.isAlive(worker.process.pid);
     if (results.worker_emitDisconnect > 0) {
-      process.nextTick(function() { finish_test(); });
+      process.nextTick(() => finish_test());
     }
-  });
+  }));
 
-  var finish_test = function() {
+  const finish_test = function() {
     try {
       checkResults(expected_results, results);
     } catch (exc) {
-      console.error('FAIL: ' + exc.message);
-      if (exc.name != 'AssertionError') {
+      if (exc.name !== 'AssertionError') {
         console.trace(exc);
       }
 
@@ -105,26 +99,13 @@ if (cluster.isWorker) {
 // some helper functions ...
 
 function checkResults(expected_results, results) {
-  for (var k in expected_results) {
+  for (const k in expected_results) {
     const actual = results[k];
     const expected = expected_results[k];
 
-    var msg = (expected[1] || '') +
-              (' [expected: ' + expected[0] + ' / actual: ' + actual + ']');
-
-    if (expected && expected.length) {
-      assert.equal(actual, expected[0], msg);
-    } else {
-      assert.equal(actual, expected, msg);
-    }
-  }
-}
-
-function alive(pid) {
-  try {
-    process.kill(pid, 'SIGCONT');
-    return true;
-  } catch (e) {
-    return false;
+    assert.strictEqual(actual,
+                       expected && expected.length ? expected[0] : expected,
+                       (expected[1] || '') +
+                         ` [expected: ${expected[0]} / actual: ${actual}]`);
   }
 }