"node is null" when manipulating an array state in a Snippet

[ChristopheCorbalan]

Describe the bug

When re-arranging an array state which is displayed inside an {#each} block via a snippet it does trigger an error saying "node is null".

The bug disappear if I remove the key parameter in the each block or if I don't use the snippet.

Reproduction

REPL

Logs

No response

System Info

System:
    OS: macOS 14.4
    CPU: (12) arm64 Apple M2 Max
    Memory: 8.70 GB / 32.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 20.6.1 - ~/.nvm/versions/node/v20.6.1/bin/node
    npm: 10.1.0 - ~/.nvm/versions/node/v20.6.1/bin/npm
    bun: 1.1.13 - ~/.bun/bin/bun
  Browsers:
    Chrome: 126.0.6478.114
    Firefox Nightly: 128.0a1
    Safari: 17.4

Severity

blocking an upgrade

[ChristopheCorbalan]

This bug seems to be happening since svelte@5.0.0-next.163

[trueadm]

Seems related to #12123 @dummdidumm.

[dummdidumm]

Locally reverted that commit, didn't change anything. This must be from another version.
My guess is this happens because of the if block: the entries are not all of the same length (dom-node-wise) so the move function inside the each somehow breaks.

[trueadm]

@dummdidumm Thanks for validating, I think I know what this is regarding now.