From 2c478175cb091bbea95fabb45f450779d91d4d36 Mon Sep 17 00:00:00 2001
From: Robert Nagy <ronagy@icloud.com>
Date: Sun, 26 Apr 2020 11:16:43 +0200
Subject: [PATCH 1/2] stream: write should throw on unknown encoding

Validate encoding passed to write(chunk, encoding, cb) and
throw if it is invalid.
---
 lib/_stream_writable.js                       |  2 ++
 .../test-stream-writable-write-error.js       | 22 +++++++++++++------
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/lib/_stream_writable.js b/lib/_stream_writable.js
index 3f7989ab097de0..a02caf2a378e9a 100644
--- a/lib/_stream_writable.js
+++ b/lib/_stream_writable.js
@@ -264,6 +264,8 @@ Writable.prototype.write = function(chunk, encoding, cb) {
   } else {
     if (!encoding)
       encoding = state.defaultEncoding;
+    else if (encoding !== 'buffer' && !Buffer.isEncoding(encoding))
+      throw new ERR_UNKNOWN_ENCODING(encoding);
     if (typeof cb !== 'function')
       cb = nop;
   }
diff --git a/test/parallel/test-stream-writable-write-error.js b/test/parallel/test-stream-writable-write-error.js
index eb9b1db06b772b..7d984aca111702 100644
--- a/test/parallel/test-stream-writable-write-error.js
+++ b/test/parallel/test-stream-writable-write-error.js
@@ -4,17 +4,17 @@ const assert = require('assert');
 
 const { Writable } = require('stream');
 
-function expectError(w, arg, code, sync) {
+function expectError(w, args, code, sync) {
   if (sync) {
     if (code) {
-      assert.throws(() => w.write(arg), { code });
+      assert.throws(() => w.write(...args), { code });
     } else {
-      w.write(arg);
+      w.write(...args);
     }
   } else {
     let errorCalled = false;
     let ticked = false;
-    w.write(arg, common.mustCall((err) => {
+    w.write(...args, common.mustCall((err) => {
       assert.strictEqual(ticked, true);
       assert.strictEqual(errorCalled, false);
       assert.strictEqual(err.code, code);
@@ -34,7 +34,7 @@ function test(autoDestroy) {
       _write() {}
     });
     w.end();
-    expectError(w, 'asd', 'ERR_STREAM_WRITE_AFTER_END');
+    expectError(w, ['asd'], 'ERR_STREAM_WRITE_AFTER_END');
   }
 
   {
@@ -50,7 +50,7 @@ function test(autoDestroy) {
       autoDestroy,
       _write() {}
     });
-    expectError(w, null, 'ERR_STREAM_NULL_VALUES', true);
+    expectError(w, [null], 'ERR_STREAM_NULL_VALUES', true);
   }
 
   {
@@ -58,7 +58,15 @@ function test(autoDestroy) {
       autoDestroy,
       _write() {}
     });
-    expectError(w, {}, 'ERR_INVALID_ARG_TYPE', true);
+    expectError(w, [{}], 'ERR_INVALID_ARG_TYPE', true);
+  }
+
+  {
+    const w = new Writable({
+      autoDestroy,
+      _write() {}
+    });
+    expectError(w, ['asd', 'noencoding'], 'ERR_UNKNOWN_ENCODING', true);
   }
 }
 

From 017b240be38028406c5921b69739fec040a709df Mon Sep 17 00:00:00 2001
From: Robert Nagy <ronagy@icloud.com>
Date: Sun, 26 Apr 2020 13:00:36 +0200
Subject: [PATCH 2/2] fixup: explicit decodeString=false

---
 test/parallel/test-stream-writable-write-error.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/parallel/test-stream-writable-write-error.js b/test/parallel/test-stream-writable-write-error.js
index 7d984aca111702..069e32e1be8e3e 100644
--- a/test/parallel/test-stream-writable-write-error.js
+++ b/test/parallel/test-stream-writable-write-error.js
@@ -63,6 +63,7 @@ function test(autoDestroy) {
 
   {
     const w = new Writable({
+      decodeStrings: false,
       autoDestroy,
       _write() {}
     });