Remote form functions: errors caught in enhance always return status code 500

[cnolte]

Describe the bug

Hello everyone,

I want to retrieve the error status code 400 from a form remote function. The problem is that when I catch the error in enhance, it has a status of 500 instead of 400. However, when I check Chrome DevTools, I can see that the remote function responds with a 400 status. Is this a bug, or is there another way to access the response status?

Reproduction

I have the following remote function:

export const update = form(async (data) => {
  error(400, 'Some error')
}

In my form I try to get the status code from the error:

<form {...update.enhance(async ({ submit }) => {
    try {
      await submit()
    } catch(err) {
      console.log(err.status) // This logs 500
    }
  })}
>
  <button type="submit">Update</button>
</form>

Logs

System Info

System:
    OS: macOS 15.6
    CPU: (10) arm64 Apple M1 Pro
    Memory: 794.78 MB / 32.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 24.3.0 - /opt/homebrew/bin/node
    npm: 11.4.2 - /opt/homebrew/bin/npm
    pnpm: 10.12.4 - /opt/homebrew/bin/pnpm
    bun: 1.2.17 - /opt/homebrew/bin/bun
  Browsers:
    Chrome: 139.0.7258.128
    Safari: 18.6
  npmPackages:
    @auth/sveltekit: ^1.10.0 => 1.10.0 
    @eslint/compat: ^1.3.2 => 1.3.2 
    @eslint/js: ^9.33.0 => 9.33.0 
    @inlang/paraglide-js: ^2.2.0 => 2.2.0 
    @playwright/test: ^1.54.2 => 1.54.2 
    @sentry/sveltekit: 10.5.0 => 10.5.0 
    @sveltejs/adapter-node: ^5.3.1 => 5.3.1 
    @sveltejs/kit: ^2.31.1 => 2.31.1 
    @sveltejs/vite-plugin-svelte: ^6.1.2 => 6.1.2 
    @tailwindcss/vite: ^4.1.12 => 4.1.12 
    @types/papaparse: ^5.3.16 => 5.3.16 
    esbuild: ^0.25.9 => 0.25.9 
    eslint: ^9.33.0 => 9.33.0 
    eslint-config-prettier: ^10.1.8 => 10.1.8 
    eslint-plugin-svelte: ^3.11.0 => 3.11.0 
    exceljs: ^4.4.0 => 4.4.0 
    globals: ^16.3.0 => 16.3.0 
    googleapis: ^156.0.0 => 156.0.0 
    msw: ^2.10.5 => 2.10.5 
    noph-ui: ^0.22.5 => 0.22.5 
    papaparse: ^5.5.3 => 5.5.3 
    prettier: ^3.6.2 => 3.6.2 
    prettier-plugin-svelte: ^3.4.0 => 3.4.0 
    prettier-plugin-tailwindcss: ^0.6.14 => 0.6.14 
    svelte: ^5.38.2 => 5.38.2 
    svelte-check: ^4.3.1 => 4.3.1 
    tailwindcss: ^4.1.12 => 4.1.12 
    typescript: ^5.9.2 => 5.9.2 
    typescript-eslint: ^8.39.1 => 8.39.1 
    vite: ^7.1.2 => 7.1.2 
    vitest: ^3.2.4 => 3.2.4 
    zod: ^4.0.17 => 4.0.17

Severity

blocking an upgrade

Additional Information

No response

[cnolte]

Thaaaaank you