Svelte5: $inspect fails when an nested array/object inside state is not present after state update

[xl0]

Describe the bug

Array inside state fails:

let s = $state({ a: [1, 2, 3] });
...
s = {}'

https://svelte-5-preview.vercel.app/#H4sIAAAAAAAAA5WQwWrDMBBEf2VRApFB2LS9Obah9BNyjHJQFDkRlVfC2rQUoX8vsiEt9NTjDjszuy-x0ToTWXtMDNVkWMteQ2CC0VcoQ_wwjgwTLPr7rIvSRT3bQOAUXnvJKEo2SJRkp-Bngjc_BY8GCcbZT7Crm4dSr2G7vcRicIYgQg_bSIoMT6BaOD4JeBbwcoJc7SV2zVpWCrA734k8gkftrH7vE6-gH4CXjJSrPBwMwaFkdc26utjSxo4Qa5VLZ9oYpW9lBBVBCbCLLKn7ufts8dKqPsVaHe0pQ7O8l5rizBJTY8cskQk2-Ysdrbmwlua7yeJB8JH1f44AAAVMAlXQlFvU2RleQS5zmH2IvFoIltWtxRiMJq6q-tPSjXMSoBcu2mP0ztTOX1dxdf1C2oUhqdw1Yfj7zCl_A7tXesIaAgAA

Error:

Uncaught TypeError: Cannot read properties of undefined (reading '0')
    at get a (playground:output:3973:23)
    at eval (playground:output:3931:26)
    at eval (playground:output:3303:55)
    at update_reaction (playground:output:2104:57)
    at update_effect (playground:output:2243:19)
    at set (playground:output:422:8)
    at HTMLButtonElement.on_click (playground:output:3945:27)
    at HTMLBodyElement.handle_event_propagation (playground:output:2817:11)

While a plain $state([]) seems to work - I'm getting update with undefined as expected:
https://svelte-5-preview.vercel.app/#H4sIAAAAAAAAA5WQwWrDMBBEf2VRApFB2LS9ObKh9BNytHxQFDkRlSVhbVqK0L8X2ZAWeupxh53ZnZfIZKyOpB0ScXLWpCWvIRBG8CuUIX5oi5owEv19UUXhUS0mIFjprp0gGAXphRNo5uAXhDc_B--0Q5gWP8Ohbh5KvYUdjsIVg9UIETrYR5So6fDE4JnBy1gdhePNdqUkO36-I3oH3ilr1HuXaAVdD7SYh7HK_UkjnEoIb7bV1ZZ2ZoKYy6m001LdIIKMIBmYVRTIf549G3dpZZfiYMYMzdooNcWVhUuNmbJwhJHZX8xk9IW0uNx1Zg9oj6T_owMAKCwSyEKjfCLPVtMKcpnD4kOk1QqtrO6Ni0ErpLKqPw3eKEUGaiWivIve6tr66yZurl8weeiTzLwJ_d8yY_4G81ONhA0CAAA=

Reproduction

Run in playground

Logs

No response

System Info

5.0.0-next.264

Severity

annoyance

[xl0]

Could be related to
#13494

I tried the proposed PR, and it did not seem to resolve the issue @trueadm

[xl0]

Update:
This is not limited to arrays:

	let s = $state({ a: {"1": "a", "2": "b"} });
       ...

{#if s.a}
	{#each Object.entries(s.a) as [k, v]}
		<Component bind:a={s.a[k]} />
	{/each}
{/if}

fails too:
https://svelte-5-preview.vercel.app/#H4sIAAAAAAAAA5WQQUvEMBCF_8owCptCadFjbQviD_DgcbOHNDt147ZJaGZXJOS_S1pYBU8e32Pem5kv4mgmCtjsI1o1Ezb47D2WyF8-i3CliQlLDO6y6Oy0QS_GM0zKvncSOUjspZVsZu8Whhc3e2fJMoyLm2FX1Ten2sp2T9LmwEQMATq4D6yYRATVQJT4ILEBiUpiCRIfNzVITJCKJ2nbetufd9p2uDA7C87qyehzF0UBXQ8i18ZUpP6NGN5yfVtvo2ss3pkRQqVSPiPekdIneB0-SHNFlhdDQYRKFaAC7M8lXA_roOT257nB2GOjuhgqtT8fEtQrg1jnriRtrM2YpMUSZ3c0o6EjNrxcKJU3zLeu_8MGAMj0IqjML9-iholEASlrvzgfRLFizqP3xgZPmoUqqk_DJyG4BL2S0s4GN1E1uffN3FK_ILe-jyq1te__PnNI3-N1kO4_AgAA

[trueadm]

This is a different issue from #13494.

[xl0]

@trueadm This is in .269, right? I'm still seeing the exact same issue with 269.

[xl0]

Nah, all good. The error is shown (which is mildly annoying), but no exception.