cluster: Added test which spawns multiple workers for cluster to work with NODE_OPTIONS="--inspect"

    When using cluster and --inspect as cli argument it is correctly
    handled and each worker will use a different port, this was
    fixed by nodejs#13619. But when env var NODE_OPTIONS="--inspect"
    is set this logic doesn't apply and the workers will fail as they
    try to attach to the same port.

    Fixes: nodejs#19026

Author: sameer-coder

lib/internal/cluster/master.js

@@ -103,13 +103,13 @@ function createWorkerProcess(id, env) {
   const execArgv = cluster.settings.execArgv.slice();
   const debugArgRegex = /--inspect(?:-brk|-port)?|--debug-port/;
   const nodeOptions = process.env.NODE_OPTIONS ?
-    process.env.NODE_OPTIONS.split(' ') : [];
+    process.env.NODE_OPTIONS : '';
 
   util._extend(workerEnv, env);
   workerEnv.NODE_UNIQUE_ID = '' + id;
 
   if (execArgv.some((arg) => arg.match(debugArgRegex)) ||
-      nodeOptions.some((arg) => arg.match(debugArgRegex))) {
+      nodeOptions.match(debugArgRegex)) {
     let inspectPort;
     if ('inspectPort' in cluster.settings) {
       if (typeof cluster.settings.inspectPort === 'function')

test/parallel/test-inspect-support-for-node_options.js

@@ -2,26 +2,31 @@
 const common = require('../common');
 const cluster = require('cluster');
 const assert = require('assert');
+const numCPUs = require('os').cpus().length;
 
-if (process.config.variables.node_without_node_options)
-  common.skip('missing NODE_OPTIONS support');
-
+common.skipIfInspectorDisabled();
 
 checkForInspectSupport('--inspect');
 
 function checkForInspectSupport(flag) {
-  const env = Object.assign({}, process.env, { NODE_OPTIONS: flag });
-  const o = JSON.stringify(flag);
+
+  const nodeOptions = JSON.stringify(flag);
+  process.env.NODE_OPTIONS = flag;
 
   if (cluster.isMaster) {
-    cluster.fork(env);
+    for (let i = 0; i < numCPUs; i++) {
+      cluster.fork();
+    }
 
     cluster.on('online', (worker) => {
-      process.exit(0);
+      worker.disconnect();
     });
 
     cluster.on('exit', (worker, code, signal) => {
-      assert.fail(`For ${o}, failed to start a cluster with inspect option`);
+      if (worker.exitedAfterDisconnect === false) {
+        assert.fail(`For ${nodeOptions}, failed to start cluster\
+ with inspect option`);
+      }
     });
   }
 }