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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
import { assert } from "../testing/asserts.ts";
/** Compare to array buffers or data views in a way that timing based attacks * cannot gain information about the platform. */export function timingSafeEqual(  a: ArrayBufferView | ArrayBufferLike | DataView,  b: ArrayBufferView | ArrayBufferLike | DataView,): boolean {  if (a.byteLength !== b.byteLength) {    return false;  }  if (!(a instanceof DataView)) {    a = new DataView(ArrayBuffer.isView(a) ? a.buffer : a);  }  if (!(b instanceof DataView)) {    b = new DataView(ArrayBuffer.isView(b) ? b.buffer : b);  }  assert(a instanceof DataView);  assert(b instanceof DataView);  const length = a.byteLength;  let out = 0;  let i = -1;  while (++i < length) {    out |= a.getUint8(i) ^ b.getUint8(i);  }  return out === 0;}