missing params if route contains errors

Describe the bug

If a route contains an error (unhandled fetch-requests, errors in a component, etc.) then the __error.svelte file gets rendered. This will also call the load function from the __layout.svelte file, like a normal request would do. Except that the params object is empty.

In a production application I use the slug to get the locale from the url e.g. /en/settings. When something fails then I no longer have the locale information in the params object and I need to use a workaround to get the locale.

const lang = params.lang || url.pathname.split('/')[1]

In this case it’s simple and I know the position of the param, but for other cases it would be good if the params could also be accessed when a error page is rendered.

Reproduction

Here is a demo repository with a short description in the README.md: https://github.com/ivanhofer/sveltekit-missing-params

Logs

No response

System Info

System:
    OS: Linux 5.10 Ubuntu 20.04.3 LTS (Focal Fossa)
    CPU: (8) x64 11th Gen Intel(R) Core(TM) i7-11370H @ 3.30GHz
    Memory: 2.63 GB / 7.66 GB
    Container: Yes
    Shell: 5.8 - /usr/bin/zsh
  Binaries:
    Node: 16.13.1 - ~/.volta/tools/image/node/16.13.1/bin/node
    Yarn: 1.22.17 - ~/.volta/tools/image/yarn/1.22.17/bin/yarn
    npm: 8.1.2 - ~/.volta/tools/image/node/16.13.1/bin/npm
  npmPackages:
    @sveltejs/adapter-auto: next => 1.0.0-next.17 
    @sveltejs/kit: next => 1.0.0-next.251 
    svelte: ^3.44.0 => 3.46.3

Severity

serious, but I can work around it

Additional Information

No response

[Rich-Harris]

Since #4344, params are available in error pages: https://stackblitz.com/edit/sveltejs-kit-template-default-h6by79?file=src%2Froutes%2Findex.svelte&terminal=dev

[EstebanBorai]

@Badlapje thanks for taking the time! Yeah Im applying the workaround.