Attempting to rename destructured slot variable keys results in a compilation error

[joelmukuthu]

Describe the bug

When using slot variables, if you have a variable that's an object and you try to destructure it there's no problem:

<!-- this is fine: -->
<Component let:data={{ foo, bar, baz }} />

However, if you try to rename some key in the object, or destructure a nested object, a compilation error is thrown:

<!-- this fails: -->
<Component let:data={{ foo: fooRenamed }} />
<!-- so does this: -->
<Component let:data={{ bar: { nestedInBar } }} />

Interestringly, the Svelte for VS Code extension doesn't show any errors on the destructured code, perhaps because it's valid javascript.

Reproduction

https://svelte.dev/repl/98917cf206794f20a4d3c45d012583be?version=3.58.0

Logs

Stack trace from svelte.repl:

TypeError: Cannot read properties of undefined (reading 'index')
    at get_slot_definition.ts:60:88
    at Array.map (<anonymous>)
    at get_slot_definition (get_slot_definition.ts:60:33)
    at new SlotTemplateWrapper (SlotTemplate.ts:57:4)
    at index.ts:92:52
    at Array.map (<anonymous>)
    at new InlineComponentWrapper (index.ts:92:39)
    at new FragmentWrapper (Fragment.ts:124:21)
    at new Renderer (Renderer.ts:90:19)
    at dom (index.ts:23:19)

System Info

Svelte: v3.58.0
All browsers

Severity

annoyance

[joelmukuthu]

I'd like to work on this and could use some help getting started. Am I missing something or are there no tests for get_slot_definition.ts? Is there a way I can test any changes I make to that file?

[dummdidumm]

Fixed in Svelte 5