From b020ac6adb5b6c3a1058d5ee2877f44da7aa0516 Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Fri, 1 Feb 2019 06:27:04 -0800
Subject: [PATCH 1/2] worker: do not throw on property access or postMessage
 after termination.

---
 lib/internal/worker.js                    |  8 +++++
 test/parallel/test-worker-safe-getters.js | 38 +++++++++++++++++++++++
 2 files changed, 46 insertions(+)
 create mode 100644 test/parallel/test-worker-safe-getters.js

diff --git a/lib/internal/worker.js b/lib/internal/worker.js
index 1640a9dd88a2ba..da663798148441 100644
--- a/lib/internal/worker.js
+++ b/lib/internal/worker.js
@@ -184,6 +184,8 @@ class Worker extends EventEmitter {
   }
 
   postMessage(...args) {
+    if (this[kPublicPort] === null) return;
+
     this[kPublicPort].postMessage(...args);
   }
 
@@ -219,14 +221,20 @@ class Worker extends EventEmitter {
   }
 
   get stdin() {
+    if (this[kParentSideStdio] === null) return null;
+
     return this[kParentSideStdio].stdin;
   }
 
   get stdout() {
+    if (this[kParentSideStdio] === null) return null;
+
     return this[kParentSideStdio].stdout;
   }
 
   get stderr() {
+    if (this[kParentSideStdio] === null) return null;
+
     return this[kParentSideStdio].stderr;
   }
 }
diff --git a/test/parallel/test-worker-safe-getters.js b/test/parallel/test-worker-safe-getters.js
new file mode 100644
index 00000000000000..099fb8093ee3e1
--- /dev/null
+++ b/test/parallel/test-worker-safe-getters.js
@@ -0,0 +1,38 @@
+'use strict';
+
+const common = require('../common');
+
+const assert = require('assert');
+const { Worker, isMainThread } = require('worker_threads');
+
+if (isMainThread) {
+  const w = new Worker(__filename, {
+    stdin: true,
+    stdout: true,
+    stderr: true
+  });
+
+  w.on('exit', common.mustCall((code) => {
+    assert.strictEqual(code, 0);
+
+    // `postMessage` should not throw after termination
+    // (this mimics the browser behavior).
+    assert.doesNotThrow(() => w.postMessage('foobar'));
+    assert.doesNotThrow(() => w.ref());
+    assert.doesNotThrow(() => w.unref());
+
+    // Although not browser specific, probably wise to
+    // make sure the stream getters don't throw either.
+    assert.doesNotThrow(() => w.stdin);
+    assert.doesNotThrow(() => w.stdout);
+    assert.doesNotThrow(() => w.stderr);
+
+    // Sanity check.
+    assert.strictEqual(w.threadId, -1);
+    assert.strictEqual(w.stdin, null);
+    assert.strictEqual(w.stdout, null);
+    assert.strictEqual(w.stderr, null);
+  }));
+} else {
+  process.exit(0);
+}

From 8cdd3ec0c49df2da3531fbfb4247af17d43a7edd Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Fri, 1 Feb 2019 07:42:00 -0800
Subject: [PATCH 2/2] test: have parallel/test-worker-safe-getters.js abide by
 lint rules.

---
 test/parallel/test-worker-safe-getters.js | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/test/parallel/test-worker-safe-getters.js b/test/parallel/test-worker-safe-getters.js
index 099fb8093ee3e1..23c8de7c7b0cfb 100644
--- a/test/parallel/test-worker-safe-getters.js
+++ b/test/parallel/test-worker-safe-getters.js
@@ -17,15 +17,15 @@ if (isMainThread) {
 
     // `postMessage` should not throw after termination
     // (this mimics the browser behavior).
-    assert.doesNotThrow(() => w.postMessage('foobar'));
-    assert.doesNotThrow(() => w.ref());
-    assert.doesNotThrow(() => w.unref());
+    w.postMessage('foobar');
+    w.ref();
+    w.unref();
 
     // Although not browser specific, probably wise to
     // make sure the stream getters don't throw either.
-    assert.doesNotThrow(() => w.stdin);
-    assert.doesNotThrow(() => w.stdout);
-    assert.doesNotThrow(() => w.stderr);
+    w.stdin;
+    w.stdout;
+    w.stderr;
 
     // Sanity check.
     assert.strictEqual(w.threadId, -1);