'PageLoad is declared but its value is never read' when running svelte-check

[camargo]

Describe the bug

When running svelte-check against a new project with a +page.ts that uses the PageLoad type, the PageLoad type is not used in the generated proxy+page.ts in the .svelte-kit directory. This causes the hint 'PageLoad' is declared but its value is never read to be thrown.

Reproduction

Create a new Svelte Kit app:

npm create svelte@latest my-app

Need to install the following packages:
  create-svelte@latest
Ok to proceed? (y) y

create-svelte version 2.0.0-next.161

Welcome to SvelteKit!

This is beta software; expect bugs and missing features.

Problems? Open an issue on https://github.com/sveltejs/kit/issues if none exists already.

✔ Which Svelte app template? › SvelteKit demo app
✔ Add type checking with TypeScript? › Yes, using TypeScript syntax
✔ Add ESLint for code linting? Yes
✔ Add Prettier for code formatting? Yes
✔ Add Playwright for browser testing? Yes

Install dependencies:

cd my-app
npm i

Add the following code to the end of src/routes/about/+page.ts:

import type { PageLoad } from './$types';

export const load: PageLoad = () => {
  console.log('loading about page');
  return {};
};

Run Svelte Check:

npm run check

Logs

npm run check

> my-app@0.0.1 check
> svelte-kit sync && svelte-check --tsconfig ./tsconfig.json


====================================
Loading svelte-check in workspace: /Users/ccamargo/Projects/my-app
Getting Svelte diagnostics...

/Users/ccamargo/Projects/my-app/.svelte-kit/types/src/routes/about/proxy+page.ts:15:1
Hint: 'PageLoad' is declared but its value is never read. 

import type { PageLoad } from './$types';

System Info

System:
  OS: macOS 11.6.8
  CPU: (16) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
  Memory: 275.84 MB / 16.00 GB
  Shell: 5.8 - /bin/zsh
Binaries:
  Node: 16.14.2 - /usr/local/opt/node@16/bin/node
  Yarn: 1.22.17 - /usr/local/bin/yarn
  npm: 8.5.0 - /usr/local/opt/node@16/bin/npm
Browsers:
  Chrome: 104.0.5112.101
  Edge: 104.0.1293.63
  Firefox: 101.0.1
  Safari: 15.6
npmPackages:
  @sveltejs/adapter-auto: next => 1.0.0-next.66 
  @sveltejs/kit: next => 1.0.0-next.440 
  svelte: ^3.46.0 => 3.49.0 
  vite: ^3.0.8 => 3.0.9

Severity

annoyance

Additional Information

Here is the resulting section of the proxy+page.ts file in .svelte-kit:

import type { PageLoad } from './$types';

export const load = () => {
  console.log('loading about page');
  return {};
};

Notice PageLoad is imported but not used.

[camargo]

Hi @dummdidumm. I am still seeing this issue with the latest version. It seems the appended type from the fix is not being recognized as the imported type.

One option would be to append <PageLoad>{} instead so the imported type is recognized.

[dummdidumm]

Ah yeah, my bad, that way it's recognized as a value, not a type. Will fix.