From a4e725810ea18db2e948bfca49c264edde2a26b3 Mon Sep 17 00:00:00 2001
From: junderw <junderwood@bitcoinbank.co.jp>
Date: Sat, 16 Oct 2021 20:17:56 +0900
Subject: [PATCH 1/3] Fix: NodeJS Buffer behavior differed, also perf
 improvement on hex parsing

---
 index.js                        | 20 +++++++++++++++++---
 test/node/test-buffer-badhex.js |  6 ++++++
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/index.js b/index.js
index cc199262..99e6b76c 100644
--- a/index.js
+++ b/index.js
@@ -844,9 +844,12 @@ function hexWrite (buf, string, offset, length) {
   }
   let i
   for (i = 0; i < length; ++i) {
-    const parsed = parseInt(string.substr(i * 2, 2), 16)
-    if (numberIsNaN(parsed)) return i
-    buf[offset + i] = parsed
+    const a = hexCharValueTable[string[i * 2]]
+    const b = hexCharValueTable[string[i * 2 + 1]]
+    if (a === undefined || b === undefined) {
+      return i
+    }
+    buf[offset + i] = a << 4 | b
   }
   return i
 }
@@ -2098,6 +2101,17 @@ const hexSliceLookupTable = (function () {
   return table
 })()
 
+// Lookup table for Buffer.from(x, 'hex')
+const hexCharValueTable = (function () {
+  const alphabet = '0123456789abcdefABCDEF'
+  const table = {}
+  for (let i = 0; i < 22; ++i) {
+    // ABCDEF should be same value as abcdef
+    table[alphabet[i]] = i < 16 ? i : i - 6
+  }
+  return table
+})()
+
 // Return not function with Error if BigInt not supported
 function defineBigIntMethod (fn) {
   return typeof BigInt === 'undefined' ? BufferBigIntNotDefined : fn
diff --git a/test/node/test-buffer-badhex.js b/test/node/test-buffer-badhex.js
index a6388e31..486e166c 100644
--- a/test/node/test-buffer-badhex.js
+++ b/test/node/test-buffer-badhex.js
@@ -14,6 +14,12 @@ const assert = require('assert');
   assert.strictEqual(buf.write('abcdef01', 0, 'hex'), 4);
   assert.deepStrictEqual(buf, new Buffer([0xab, 0xcd, 0xef, 0x01]));
   assert.strictEqual(buf.toString('hex'), 'abcdef01');
+  // Node Buffer behavior check
+  // > Buffer.from('abc def01','hex')
+  // <Buffer ab>
+  assert.strictEqual(buf.write('abc def01', 0, 'hex'), 1);
+  assert.deepStrictEqual(buf, new Buffer([0xab]));
+  assert.strictEqual(buf.toString('hex'), 'ab');
 
   const copy = Buffer.from(buf.toString('hex'), 'hex');
   assert.strictEqual(buf.toString('hex'), copy.toString('hex'));

From ddd37ec84287d37fc5136ae1835b27324e9c7e1a Mon Sep 17 00:00:00 2001
From: junderw <junderwood@bitcoinbank.co.jp>
Date: Sat, 16 Oct 2021 21:54:29 +0900
Subject: [PATCH 2/3] Add myself to AUTHORS.md with the script

---
 AUTHORS.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/AUTHORS.md b/AUTHORS.md
index 468aa190..3f4918c7 100644
--- a/AUTHORS.md
+++ b/AUTHORS.md
@@ -69,5 +69,6 @@
 - jkkang (jkkang@smartauth.kr)
 - Deklan Webster (deklanw@gmail.com)
 - Martin Heidegger (martin.heidegger@gmail.com)
+- junderw (junderwood@bitcoinbank.co.jp)
 
 #### Generated by bin/update-authors.sh.

From d2d197807628d1dad8cf336a7bc68e5f13ae570a Mon Sep 17 00:00:00 2001
From: Daniel Cousens <413395+dcousens@users.noreply.github.com>
Date: Wed, 11 Oct 2023 15:43:14 +1100
Subject: [PATCH 3/3] prefer constant table

---
 index.js | 35 +++++++++++++++++++++++++----------
 1 file changed, 25 insertions(+), 10 deletions(-)

diff --git a/index.js b/index.js
index 99e6b76c..4c24ca8b 100644
--- a/index.js
+++ b/index.js
@@ -2101,16 +2101,31 @@ const hexSliceLookupTable = (function () {
   return table
 })()
 
-// Lookup table for Buffer.from(x, 'hex')
-const hexCharValueTable = (function () {
-  const alphabet = '0123456789abcdefABCDEF'
-  const table = {}
-  for (let i = 0; i < 22; ++i) {
-    // ABCDEF should be same value as abcdef
-    table[alphabet[i]] = i < 16 ? i : i - 6
-  }
-  return table
-})()
+// hex lookup table for Buffer.from(x, 'hex')
+const hexCharValueTable = {
+  '0': 0, 
+  '1': 1,
+  '2': 2,
+  '3': 3,
+  '4': 4,
+  '5': 5,
+  '6': 6,
+  '7': 7,
+  '8': 8,
+  '9': 9,
+  a: 10,
+  b: 11,
+  c: 12,
+  d: 13,
+  e: 14,
+  f: 15,
+  A: 10,
+  B: 11,
+  C: 12,
+  D: 13,
+  E: 14,
+  F: 15
+}
 
 // Return not function with Error if BigInt not supported
 function defineBigIntMethod (fn) {