From 255352a0fcaf5c21374718371222a96395736adb Mon Sep 17 00:00:00 2001
From: Paul Miller <paul@paulmillr.com>
Date: Tue, 5 Mar 2024 01:45:37 +0000
Subject: [PATCH] Debug import bug

---
 benchmark/bug.js |  5 +++++
 src/utils.ts     | 12 +++++++++---
 2 files changed, 14 insertions(+), 3 deletions(-)
 create mode 100644 benchmark/bug.js

diff --git a/benchmark/bug.js b/benchmark/bug.js
new file mode 100644
index 0000000..ec67cdb
--- /dev/null
+++ b/benchmark/bug.js
@@ -0,0 +1,5 @@
+const { scrypt } = require('../scrypt.js');
+let start = Date.now();
+scrypt('password', 'salt', { N: 2 ** 15, r: 8, p: 1, dkLen: 32 })
+let end = Date.now();
+console.log(end - start, 'ms');
\ No newline at end of file
diff --git a/src/utils.ts b/src/utils.ts
index 03582db..8e0ada9 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -7,7 +7,15 @@
 // Makes the utils un-importable in browsers without a bundler.
 // Once node.js 18 is deprecated (2025-04-30), we can just drop the import.
 import { crypto } from '@noble/hashes/crypto';
-import { isBytes, bytes as abytes } from './_assert.js';
+import { bytes as abytes } from './_assert.js';
+// export { isBytes } from './_assert.js';
+// We can't reuse isBytes from _assert, because somehow this causes huge perf issues
+export function isBytes(a: unknown): a is Uint8Array {
+  return (
+    a instanceof Uint8Array ||
+    (a != null && typeof a === 'object' && a.constructor.name === 'Uint8Array')
+  );
+}
 
 // prettier-ignore
 export type TypedArray = Int8Array | Uint8ClampedArray | Uint8Array |
@@ -38,8 +46,6 @@ export const byteSwap = (word: number) =>
 // Conditionally byte swap if on a big-endian platform
 export const byteSwapIfBE = isLE ? (n: number) => n : (n: number) => byteSwap(n);
 
-export { isBytes };
-
 // In place byte swap for Uint32Array
 export function byteSwap32(arr: Uint32Array) {
   for (let i = 0; i < arr.length; i++) {