Language Service Locks when you have a svelte file which doesn't start with a char in TS

[orta]

Describe the bug

To Reproduce
Steps to reproduce the behavior:

Using the npx degit sveltejs/template numbers, then making a file 1_File.svelte and editing the main.svelte to:

<script lang="ts">
	import File from "1_File.svelte"
	export let name: string;
</script>

<main>
	<h1>Hello {name}!</h1>
	<File></File>
	<p>Visit the <a href="https://svelte.dev/tutorial">Svelte tutorial</a> to learn how to build Svelte apps.</p>
</main>

Works fine in JS mode, but after running node scripts/setupTypeScript.ts then the reference to File gets an error with:

Type definitions are missing for this Svelte Component. It needs a class definition with at least the property '$$prop_def' which should contain a map of input property definitions.
Example:
class ComponentName { $$prop_def: { propertyName: string; } }

'File' cannot be used as a JSX component.
  Its instance type 'SvelteComponentDev' is not a valid JSX element.
    Property '$$prop_def' is missing in type 'SvelteComponentDev' but required in type 'ElementClass'.ts(2786)

It's very likely that somewhere there's probably an assumption that the filename can be a legal JS identifier. This can cause locks in the LSP (my guess is in file renames) which means things like formatting fail to happen.

Expected behavior

I can use any filename (I was writing a wizard and wanted my components in the order folks see them)

Screenshots
N/A

( Other than this, everything has been smooth sailing so far )

[dummdidumm]

Your assumption is correct. We assume the filename is a valid class name which the produces invalid code. We need to strip out leading invalid characters.