svelte-package: svelte-5: Using ComponentConstructorOptions in svelte.d.ts after running svelte-package

[shinokada]

Describe the bug

After running pnpm package, and checking a created svelte.d.ts file, it uses ComponentConstructorOptions with stroke line on VSCode.

'ComponentConstructorOptions' is deprecated.ts(6385)
index.d.ts(3, 5): The declaration was marked as deprecated here.

Reproduction

Create a sample component, lib/Mycompo.svelte:

<script lang="ts">
  interface Props {
    firstName: string;
    lastName: string;
  }
  let { firstName, lastName }: Props = $props();
</script>

<p>
  Hello {firstName} {lastName}
</p>

In lib/index.ts:

export { default as MyCompo } from './MyCompo.svelte'

Run pnpm package and check dist/MyCompo.svelte.d.ts

Logs

No response

System Info

System:
    OS: macOS 14.6
    CPU: (10) arm64 Apple M2 Pro
    Memory: 43.16 MB / 16.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 20.14.0 - ~/.nvm/versions/node/v20.14.0/bin/node
    npm: 10.7.0 - ~/.nvm/versions/node/v20.14.0/bin/npm
    pnpm: 9.4.0 - /opt/homebrew/bin/pnpm
    bun: 1.1.8 - ~/.bun/bin/bun
  Browsers:
    Chrome: 126.0.6478.62
    Edge: 126.0.2592.68
    Safari: 17.6
  npmPackages:
    @sveltejs/adapter-auto: ^3.2.2 => 3.2.2 
    @sveltejs/kit: ^2.5.17 => 2.5.17 
    @sveltejs/package: ^2.3.2 => 2.3.2 
    @sveltejs/vite-plugin-svelte: ^3.1.1 => 3.1.1 
    svelte: 5.0.0-next.162 => 5.0.0-next.162 
    vite: ^5.3.1 => 5.3.1

Severity

annoyance

Additional Information

No response

[jasonlyu123]

This is intentional. The component is a function in svelte 5 and the constructor signature is kept for compatibility. See sveltejs/svelte#11775 for the reasoning. Is there a specific reason why you don't want to see it or you just find that unexpected?

[shinokada]

Is it possible to adjust for Svelte 5 since it is going to be out of next version?

[dummdidumm]

No, this is intentional for backwards compatibility as the linked issue explains. We want to output both so that people can use it both way. This will be removed once Svelte 4 syntax is no longer be usable in a future major version of Svelte.

Does this output cause any issues for you in practise? Or is it just that you're wondering why it's using a deprecated syntax?

[shinokada]

Thanks. I just wanted to clarify. Since VSCode uses the line stroke, I thought I was doing something wrong.