From 4947abe88bc49eeaecb85ec12f0f3069bf2c287d Mon Sep 17 00:00:00 2001
From: Brian Gough <brian.gough@overleaf.com>
Date: Thu, 7 May 2020 10:42:05 +0100
Subject: [PATCH] fix deprecated usage of Buffer constructor

---
 services/clsi/app/js/OutputFileOptimiser.js            | 3 +--
 services/clsi/app/js/SafeReader.js                     | 2 +-
 services/clsi/test/unit/js/OutputFileOptimiserTests.js | 6 +++---
 3 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/services/clsi/app/js/OutputFileOptimiser.js b/services/clsi/app/js/OutputFileOptimiser.js
index c0b8cc141a..1af2045295 100644
--- a/services/clsi/app/js/OutputFileOptimiser.js
+++ b/services/clsi/app/js/OutputFileOptimiser.js
@@ -45,8 +45,7 @@ module.exports = OutputFileOptimiser = {
 
   checkIfPDFIsOptimised(file, callback) {
     const SIZE = 16 * 1024 // check the header of the pdf
-    const result = new Buffer(SIZE)
-    result.fill(0) // prevent leakage of uninitialised buffer
+    const result = Buffer.alloc(SIZE) // fills with zeroes by default
     return fs.open(file, 'r', function(err, fd) {
       if (err != null) {
         return callback(err)
diff --git a/services/clsi/app/js/SafeReader.js b/services/clsi/app/js/SafeReader.js
index d909e37e73..900826756a 100644
--- a/services/clsi/app/js/SafeReader.js
+++ b/services/clsi/app/js/SafeReader.js
@@ -43,7 +43,7 @@ module.exports = SafeReader = {
           }
           return callback(null, ...Array.from(result))
         })
-      const buff = new Buffer(size, 0) // fill with zeros
+      const buff = Buffer.alloc(size) // fills with zeroes by default
       return fs.read(fd, buff, 0, buff.length, 0, function(
         err,
         bytesRead,
diff --git a/services/clsi/test/unit/js/OutputFileOptimiserTests.js b/services/clsi/test/unit/js/OutputFileOptimiserTests.js
index 4546f08431..b4983bf0f8 100644
--- a/services/clsi/test/unit/js/OutputFileOptimiserTests.js
+++ b/services/clsi/test/unit/js/OutputFileOptimiserTests.js
@@ -124,7 +124,7 @@ describe('OutputFileOptimiser', function() {
       this.fs.read = sinon
         .stub()
         .withArgs(this.fd)
-        .yields(null, 100, new Buffer('hello /Linearized 1'))
+        .yields(null, 100, Buffer.from('hello /Linearized 1'))
       this.fs.close = sinon
         .stub()
         .withArgs(this.fd)
@@ -140,7 +140,7 @@ describe('OutputFileOptimiser', function() {
         this.fs.read = sinon
           .stub()
           .withArgs(this.fd)
-          .yields(null, 100, new Buffer('hello /Linearized 1'))
+          .yields(null, 100, Buffer.from('hello /Linearized 1'))
         return this.OutputFileOptimiser.checkIfPDFIsOptimised(
           this.src,
           this.callback
@@ -169,7 +169,7 @@ describe('OutputFileOptimiser', function() {
         this.fs.read = sinon
           .stub()
           .withArgs(this.fd)
-          .yields(null, 100, new Buffer('hello not linearized 1'))
+          .yields(null, 100, Buffer.from('hello not linearized 1'))
         return this.OutputFileOptimiser.checkIfPDFIsOptimised(
           this.src,
           this.callback