export function formatMs(milliseconds: number): string { if (!Number.isFinite(milliseconds)) { return 'NaN'; } const absInput = Math.abs(Math.round(milliseconds)); let millis = (absInput % 1000).toString(); if (millis.length < 3) { if (millis.length === 2) { millis = '0' + millis; } else { millis = '00' + millis; } } const seconds = Math.floor(absInput / 1_000) % 60; const minutes = Math.floor(absInput / 60_000); let output = `${seconds}.${millis}s`; if (minutes > 0) { output = `${minutes}m${output}`; } if (milliseconds < 0) { output = `-${output}`; } return output; }