// Thread-instanced fixture (prefix mt_): mutable module state each embedder
// thread's instance advances independently, allocation-heavy work that
// churns each instance's own collector, and a deliberately trapping export
// (array index OOB — the runtime's own range trap) that must reach only the
// calling thread's sink. No top-level output: four instances init
// concurrently in the probe.
import { performance } from "node:perf_hooks";

let calls = 0;

export function bump(x: number): number {
  calls++;
  return x + calls;
}

export function callsSeen(): number {
  return calls;
}

export function sumTo(n: number): number {
  const xs: number[] = [];
  for (let i = 1; i <= n; i++) xs.push(i);
  let s = 0;
  for (const x of xs) s += x;
  return s;
}

export function boom(i: number): number {
  const xs = [1, 2, 3];
  return xs[i]!;
}

export function uptime(): number {
  return process.uptime();
}

export function perfNow(): number {
  return performance.now();
}