Svelte 5: Spread args function extraction issue

[brunnerh]

Describe the bug

The compiler extracts functions to the top level scope and adds dependencies as arguments at the end.
This does not work if the function has spread arguments.

(Found by jakub on Discord.)

Reproduction

<script>
    let count = $state(0);
    function increment(...args) {
        count += 1
    }
</script>

<button on:click={increment}>
    clicks: {count}
</button>

Comma is not permitted after the rest element (6:26)

REPL

Generated JS:

function increment(...args, count) {
	$.set(count, $.get(count) + 1);
}

Logs

No response

System Info

REPL

Severity

annoyance

[dummdidumm]

Another one in the family of hoisting bugs