if (!data) {
  throw fetch()
}

Suspense는 던져진 promise를 캐치해서 resolve될 때까지 fallback을 렌더하고, resolve되면 다시 렌더한다. 던지는 건 예외와 같은 메커니즘이다.

---

• https://github.com/facebook/react/blob/eb8feb71096eec5c885b2a4c7d8d030d3622f265/packages/react/src/ReactLazy.js#L222
• https://github.com/TanStack/query/blob/b8e35598ef24855a2792414faea5721d833fa61e/packages/react-query/src/suspense.ts#L61
• https://developer.mozilla.org/ko/docs/Web/JavaScript/Reference/Statements/throw
• https://jser.pro/ddir/rie?reactVersion=18.3.1&codeKey=ud62nsxll29yy0dzba8