`writeEarlyHints` never resolves with node runtime

[pajecawav]

Environment

h3 2.0.1-rc.22
node v24.15.0

Reproduction

// server.mjs
import { H3, serve, writeEarlyHints } from "h3/node";

const app = new H3().get("/", async event => {
	await writeEarlyHints(event, {});
	return "⚡️ Tadaa!";
});

serve(app, { port: 3000 });

Or clone repo from here https://github.com/pajecawav/h3-early-hints-bug and run pnpm install && node server.mjs

Describe the bug

When using writeEarlyHints with Node runtime promise never resolves so the request handler hangs indefinitely

Additional context

No response

Logs

[pajecawav]

Apparently event.runtime?.node?.res?.writeEarlyHints doesn't execute callback when no hints were provided, so

await writeEarlyHints(event, {}); // hangs
await writeEarlyHints(event, { link: [] }); // hangs
await writeEarlyHints(event, { link: [`</test>; rel=modulepreload`] }); // resolves

h3/src/utils/response.ts

Lines 111 to 120 in 84244b4

	export function writeEarlyHints(
	event: H3Event,
	hints: Record<string, string | string[]>,
	): void | Promise<void> {
	// Use native early hints if available (Node.js)
	if (event.runtime?.node?.res?.writeEarlyHints) {
	return new Promise((resolve) => {
	event.runtime?.node?.res?.writeEarlyHints(hints, () => resolve());
	});
	}