Svelte 5: External $derived variable inside effect/inspect runes causes infinite re-renders

[zaknaj]

Describe the bug

The inspect rune in this example causes an ERR_SVELTE_TOO_MANY_UPDATES error.

The error doesn't happen when the state doesn't include an array, and instead is a primitive (the rest is the same), example

Reproduction

https://svelte-5-preview.vercel.app/#H4sIAAAAAAAAE2VRXW-cMBD8KysrD6BYoKafugBSf8f5HhxYrk7MGtkLbYT83yuby12avq1nNZ6ZnU2MxmIQh-MmSE8oDuLnPAsp-HVOj7CiZRRSBLf4PiFN6L2ZuVOk2Eyz8wwbBHYeIcLo3QRKVHUGqp1dPQclHhUlhkWG3i3E0MJdYM1Y_Cj31Z2hMGPPxc612p-xhLqGp-UMZ4cB9G_9CmYE_mUCWEMIJkDvpgmJcVDU1Ddv1Axm7baLjyRUrdrGpk7wv9usdN0oap4WZkfgqLemf2m3ooS2gy2Z_PAftHCsquoDKveIp0TI0_29ohjzyfSQje4SnZBicoMZDQ7iwH7BKK89vD_hrZDn8L6M3lFgyMK3g2ajq7YHOH6SD_Kz_CK_ym_y-0lRLBXtnBw6cQb0ZsWhuLqvRmMZfYEpNHYPZakI_-Si3-RS2e3bQTSjTNMZL78W5b5S7JEXTxetBEVF8f_Mp_gXRyQpuYcCAAA=

Logs

No response

System Info

svelte-5-preview.vercel.app

Severity

annoyance

[dummdidumm]

More minimal reproduction. Observation: When moving the code from the outside into the script tag the error doesn't show up. When removing the template code, the error doesn't show up.

[zaknaj]

The $effect rune also causes this issue, logging not even necessary

[zaknaj]

I'm pretty sure $inspect uses the $effect rune, so this might be closer to the root cause.

[zaknaj]

Even simpler reproduction

Appears that the issue is with arrays & objects in derived. State rune is irrelevant.

[zaknaj]

@trueadm I don't think it's fixed yet? maybe i'm wrong.
Only fixes the case where the derived signal has no dependency, previous 2 reproductions still bugging.