From 4cfa7e07161da1d1f164fcff9f288e1d653a872a Mon Sep 17 00:00:00 2001
From: himself65 <himself65@outlook.com>
Date: Fri, 17 Apr 2020 15:04:38 +0800
Subject: [PATCH] stream: simplify Readable push/unshift logic
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PR-URL: https://github.com/nodejs/node/pull/32899
Reviewed-By: Robert Nagy <ronagy@icloud.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Juan José Arboleda <soyjuanarbol@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
---
 lib/_stream_readable.js | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/lib/_stream_readable.js b/lib/_stream_readable.js
index ec9f86d7eacf4a..f39c49867805d3 100644
--- a/lib/_stream_readable.js
+++ b/lib/_stream_readable.js
@@ -230,13 +230,15 @@ function readableAddChunk(stream, chunk, encoding, addToFront) {
   if (!state.objectMode) {
     if (typeof chunk === 'string') {
       encoding = encoding || state.defaultEncoding;
-      if (addToFront && state.encoding && state.encoding !== encoding) {
-        // When unshifting, if state.encoding is set, we have to save
-        // the string in the BufferList with the state encoding.
-        chunk = Buffer.from(chunk, encoding).toString(state.encoding);
-      } else if (encoding !== state.encoding) {
-        chunk = Buffer.from(chunk, encoding);
-        encoding = '';
+      if (state.encoding !== encoding) {
+        if (addToFront && state.encoding) {
+          // When unshifting, if state.encoding is set, we have to save
+          // the string in the BufferList with the state encoding.
+          chunk = Buffer.from(chunk, encoding).toString(state.encoding);
+        } else {
+          chunk = Buffer.from(chunk, encoding);
+          encoding = '';
+        }
       }
     } else if (chunk instanceof Buffer) {
       encoding = '';