Function loadRun

bench/diff.js:60–85

(arg)

// ─── result loading ──────────────────────────────────────────────────────────

function loadRun(arg) {
  if (!fs.existsSync(arg)) {
    throw new Error(`not found: ${arg}`);
  }
  const stat = fs.statSync(arg);
  let target = arg;
  if (stat.isDirectory()) {
    const candidates = fs.readdirSync(arg)
      .filter((f) => f.endsWith('.json'))
      .map((f) => path.join(arg, f))
      .sort((a, b) => fs.statSync(b).mtimeMs - fs.statSync(a).mtimeMs);
    if (candidates.length === 0) throw new Error(`no .json files in ${arg}`);
    target = candidates[0];
  }
  const raw = fs.readFileSync(target, 'utf-8');
  let data;
  try {
    data = JSON.parse(raw);
  } catch (e) {
    throw new Error(`malformed JSON in ${target}: ${e.message}`);
  }
  if (!Array.isArray(data.results)) {
    throw new Error(`${target}: missing "results" array — not a harness output?`);
  }
  return { path: target, data };
}

// ─── metric extraction ───────────────────────────────────────────────────────