fix: prevent TypeError in serialize_refreshes when state.refreshes is null

[robinbraemer]

Problem

When calling redirect() in remote functions, SvelteKit crashes with:

TypeError: Cannot convert undefined or null to object
    at Object.keys (<anonymous>)
    at serialize_refreshes (packages/kit/src/runtime/server/remote.js:214:14)

This happens because:

1. Remote function calls redirect(302, '/some-path')
2. SvelteKit catches the Redirect exception and tries to create a JSON response
3. During response creation, it calls serialize_refreshes() to handle any pending refreshes
4. serialize_refreshes assumes state.refreshes is always an object, but it can be null/undefined
5. Object.keys(refreshes) throws when refreshes is null/undefined

Solution

Add a fallback to an empty object when state.refreshes is null/undefined:

const refreshes = /** @type {Record<string, Promise<any>>} */ (state.refreshes || {});

Testing

• ✅ Remote function redirects now work without crashing
• ✅ Normal remote function calls still work as expected
• ✅ The fix is minimal and doesn't affect existing functionality

Reproduction

// This would previously cause a 500 error
export const myRemoteFunction = query(async () => {
  redirect(302, '/auth/logout');
});

Impact

This is a bug fix that allows remote functions to use redirects as intended, without breaking existing functionality.

[changeset-bot]

⚠️ No Changeset found

Latest commit: adc4a89

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-14402-svelte.vercel.app/

[dummdidumm]

Thank you, the fix is correct - but #14400 also fixes this while adding tests+changeset, therefore closing in favor of that

[Rich-Harris]

merged #14400, closing — thanks