From 1e3e6da9b9bdab5ab3a5678ce9d3d178e62444b3 Mon Sep 17 00:00:00 2001
From: Robert Nagy <ronagy@icloud.com>
Date: Fri, 16 Aug 2019 10:16:23 +0200
Subject: [PATCH] stream: simplify howMuchToRead()
This slightly refactors read by moving side effects out of
howMuchToRead().
We don't actually have to set state.needReadable = true; in
howMuchToRead() since read handles 0 return as needReadable.
PR-URL: https://github.com/nodejs/node/pull/29155
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
---
lib/_stream_readable.js | 14 +++++---------
1 file changed, 5 insertions(+), 9 deletions(-)
diff --git a/lib/_stream_readable.js b/lib/_stream_readable.js
index 0d23014760741b..47c177346b7d99 100644
--- a/lib/_stream_readable.js
+++ b/lib/_stream_readable.js
@@ -377,17 +377,9 @@ function howMuchToRead(n, state) {
else
return state.length;
}
- // If we're asking for more than the current hwm, then raise the hwm.
- if (n > state.highWaterMark)
- state.highWaterMark = computeNewHighWaterMark(n);
if (n <= state.length)
return n;
- // Don't have enough
- if (!state.ended) {
- state.needReadable = true;
- return 0;
- }
- return state.length;
+ return state.ended ? state.length : 0;
}
// You can override either this method, or the async _read(n) below.
@@ -403,6 +395,10 @@ Readable.prototype.read = function(n) {
const state = this._readableState;
const nOrig = n;
+ // If we're asking for more than the current hwm, then raise the hwm.
+ if (n > state.highWaterMark)
+ state.highWaterMark = computeNewHighWaterMark(n);
+
if (n !== 0)
state.emittedReadable = false;