From ce265908eb84aa0518dcadc57d59e7fbb353a256 Mon Sep 17 00:00:00 2001
From: Ruben Bridgewater <ruben@bridgewater.de>
Date: Wed, 20 Mar 2019 12:18:16 +0100
Subject: [PATCH] http2: remove side effects from validateSettings

The function did not only validate the input so far but it also made
a copy of the input object and returned that copy to the callee
function. That copy was not necessary for all call sites and it was
not obvious that the function did not only validate the input but
that it also returned a copy of it. This makes sure the function does
nothing more than validation and copying is happening in the callee
function when required.

PR-URL: https://github.com/nodejs/node/pull/26809
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
---
 lib/internal/http2/core.js | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/internal/http2/core.js b/lib/internal/http2/core.js
index 824d7d604c9a09..69cc72c7ae5905 100644
--- a/lib/internal/http2/core.js
+++ b/lib/internal/http2/core.js
@@ -784,7 +784,7 @@ function pingCallback(cb) {
 // 6. enablePush must be a boolean
 // All settings are optional and may be left undefined
 const validateSettings = hideStackFrames((settings) => {
-  settings = { ...settings };
+  if (settings === undefined) return;
   assertWithinRange('headerTableSize',
                     settings.headerTableSize,
                     0, kMaxInt);
@@ -805,7 +805,6 @@ const validateSettings = hideStackFrames((settings) => {
     throw new ERR_HTTP2_INVALID_SETTING_VALUE('enablePush',
                                               settings.enablePush);
   }
-  return settings;
 });
 
 // Creates the internal binding.Http2Session handle for an Http2Session
@@ -1144,7 +1143,7 @@ class Http2Session extends EventEmitter {
     if (this.destroyed)
       throw new ERR_HTTP2_INVALID_SESSION();
     assertIsObject(settings, 'settings');
-    settings = validateSettings(settings);
+    validateSettings(settings);
 
     if (callback && typeof callback !== 'function')
       throw new ERR_INVALID_CALLBACK();
@@ -1152,7 +1151,7 @@ class Http2Session extends EventEmitter {
 
     this[kState].pendingAck++;
 
-    const settingsFn = submitSettings.bind(this, settings, callback);
+    const settingsFn = submitSettings.bind(this, { ...settings }, callback);
     if (this.connecting) {
       this.once('connect', settingsFn);
       return;
@@ -2817,7 +2816,8 @@ function createServer(options, handler) {
 // HTTP2-Settings header frame.
 function getPackedSettings(settings) {
   assertIsObject(settings, 'settings');
-  updateSettingsBuffer(validateSettings(settings));
+  validateSettings(settings);
+  updateSettingsBuffer({ ...settings });
   return binding.packSettings();
 }