From bf1bbe9cc3bec4e769d311717257f11832dab18d Mon Sep 17 00:00:00 2001
From: Robert Nagy <ronagy@icloud.com>
Date: Tue, 31 Dec 2019 12:43:54 +0100
Subject: [PATCH] stream: simplify Writable.write

Backport-PR-URL: https://github.com/nodejs/node/pull/32162
---
 lib/_stream_writable.js                   | 79 +++++++++--------------
 test/parallel/test-net-write-arguments.js |  2 +-
 2 files changed, 33 insertions(+), 48 deletions(-)

diff --git a/lib/_stream_writable.js b/lib/_stream_writable.js
index d2c109c302b40c..f643c96635a2c3 100644
--- a/lib/_stream_writable.js
+++ b/lib/_stream_writable.js
@@ -274,60 +274,52 @@ function writeAfterEnd(stream, cb) {
   process.nextTick(cb, er);
 }
 
-// Checks that a user-supplied chunk is valid, especially for the particular
-// mode the stream is in. Currently this means that `null` is never accepted
-// and undefined/non-string values are only allowed in object mode.
-function validChunk(stream, state, chunk, cb) {
-  var er;
-
-  if (chunk === null) {
-    er = new ERR_STREAM_NULL_VALUES();
-  } else if (typeof chunk !== 'string' && !state.objectMode) {
-    er = new ERR_INVALID_ARG_TYPE('chunk', ['string', 'Buffer'], chunk);
-  }
-  if (er) {
-    errorOrDestroy(stream, er);
-    process.nextTick(cb, er);
-    return false;
-  }
-  return true;
-}
 
 Writable.prototype.write = function(chunk, encoding, cb) {
   const state = this._writableState;
-  var ret = false;
-  const isBuf = !state.objectMode && Stream._isUint8Array(chunk);
-
-  // Do not use Object.getPrototypeOf as it is slower since V8 7.3.
-  if (isBuf && !(chunk instanceof Buffer)) {
-    chunk = Stream._uint8ArrayToBuffer(chunk);
-  }
 
   if (typeof encoding === 'function') {
     cb = encoding;
-    encoding = null;
-  }
-
-  if (isBuf)
-    encoding = 'buffer';
-  else if (!encoding)
     encoding = state.defaultEncoding;
+  } else {
+    if (!encoding)
+      encoding = state.defaultEncoding;
+    if (typeof cb !== 'function')
+      cb = nop;
+  }
 
-  if (typeof cb !== 'function')
-    cb = nop;
-
+  let err;
   if (state.ending) {
     writeAfterEnd(this, cb);
   } else if (state.destroyed) {
-    const err = new ERR_STREAM_DESTROYED('write');
+    err = new ERR_STREAM_DESTROYED('write');
+  } else if (chunk === null) {
+    err = new ERR_STREAM_NULL_VALUES();
+  } else if (!state.objectMode) {
+    if (typeof chunk === 'string') {
+      if (state.decodeStrings !== false) {
+        chunk = Buffer.from(chunk, encoding);
+        encoding = 'buffer';
+      }
+    } else if (chunk instanceof Buffer) {
+      encoding = 'buffer';
+    } else if (Stream._isUint8Array(chunk)) {
+      chunk = Stream._uint8ArrayToBuffer(chunk);
+      encoding = 'buffer';
+    } else {
+      err = new ERR_INVALID_ARG_TYPE(
+        'chunk', ['string', 'Buffer', 'Uint8Array'], chunk);
+    }
+  }
+
+  if (err) {
     process.nextTick(cb, err);
-    errorOrDestroy(this, err);
-  } else if (isBuf || validChunk(this, state, chunk, cb)) {
+    errorOrDestroy(this, err, true);
+    return false;
+  } else {
     state.pendingcb++;
-    ret = writeOrBuffer(this, state, chunk, encoding, cb);
+    return writeOrBuffer(this, state, chunk, encoding, cb);
   }
-
-  return ret;
 };
 
 Writable.prototype.cork = function() {
@@ -402,13 +394,6 @@ ObjectDefineProperty(Writable.prototype, 'writableCorked', {
 // in the queue, and wait our turn.  Otherwise, call _write
 // If we return false, then we need a drain event, so set that flag.
 function writeOrBuffer(stream, state, chunk, encoding, cb) {
-  if (!state.objectMode &&
-      state.decodeStrings !== false &&
-      encoding !== 'buffer' &&
-      typeof chunk === 'string') {
-    chunk = Buffer.from(chunk, encoding);
-    encoding = 'buffer';
-  }
   const len = state.objectMode ? 1 : chunk.length;
 
   state.length += len;
diff --git a/test/parallel/test-net-write-arguments.js b/test/parallel/test-net-write-arguments.js
index d3dde36b02f852..0e9e30b41da286 100644
--- a/test/parallel/test-net-write-arguments.js
+++ b/test/parallel/test-net-write-arguments.js
@@ -29,6 +29,6 @@ assert.throws(() => socket.write(null),
     code: 'ERR_INVALID_ARG_TYPE',
     name: 'TypeError',
     message: 'The "chunk" argument must be of type string or an instance of ' +
-              `Buffer.${common.invalidArgTypeHelper(value)}`
+              `Buffer or Uint8Array.${common.invalidArgTypeHelper(value)}`
   }));
 });