preloadCode errors during page load

[WaltzingPenguin]

Describe the bug

Calling preloadCode during initial page load results in

TypeError: Failed to construct 'URL': Invalid base URL

This issue is present in @sveltejs/kit version 2.15.0 but not present in 2.14.0

Reproduction

https://github.com/WaltzingPenguin/sveltekit-preloadCode/tree/main/src/routes/login

• Create a new SvelteKit project
• Create src/routes/login/+page.svelte with any content
• Create src/routes/login/+page.ts with

import { browser } from "$app/environment";
import { preloadCode } from "$app/navigation";
import { base } from "$app/paths";

export function load() {
  if (browser) {
    preloadCode(base)
  }
}

• Run the dev server and navigate directly to /login

Logs

No response

System Info

System:
    OS: Windows 11 10.0.22631
    CPU: (20) x64 13th Gen Intel(R) Core(TM) i5-13600KF
    Memory: 39.54 GB / 63.85 GB
  Binaries:
    Node: 20.9.0 - C:\Program Files\nodejs\node.EXE
    npm: 10.1.0 - C:\Program Files\nodejs\npm.CMD
    pnpm: 8.11.0 - ~\AppData\Local\pnpm\pnpm.CMD
  Browsers:
    Edge: Chromium (127.0.2651.74)
    Internet Explorer: 11.0.22621.3527
  npmPackages:
    @sveltejs/adapter-static: ^3.0.8 => 3.0.8
    @sveltejs/kit: ^2.15.2 => 2.15.2
    @sveltejs/vite-plugin-svelte: ^5.0.3 => 5.0.3
    svelte: ^5.17.3 => 5.17.3
    vite: ^6.0.7 => 6.0.7

Severity

blocking an upgrade

Additional Information

No response

[eltigerchino]

Calling preloadCode in load in the browser doesn't seem to work in 2.14.0 either.

The issue is that preloadCode relies on current.url but that isn't populated until after the load functions are run.

preloadCode is called when the nodes are loaded

kit/packages/kit/src/runtime/client/client.js

Line 2459 in 5b667e4

return load_node({

but current.url is only populated much later when we call initialize

kit/packages/kit/src/runtime/client/client.js

Line 448 in 5b667e4

current = result.state;