Load functions are not always re-run on user changes to URL with hash-based router

[stephenlrandall]

Describe the bug

When using router.type === 'pathname', all load functions are re-run if a user edits what would be part of $page.url.pathname (the page appears to reload).

When using router.type === 'hash', all load functions are not guaranteed to re-run when a user edits the URL. If the search params are modified, the page reloads and all load functions run. But when any part of the path (now following the hash) is edited, selective invalidation seems to be applied. This leads to inconsistent behavior between the two router types.

I don't know if this distinction between "reload on pathname change, don't reload on hash change" is just a browser thing that SvelteKit has no control over, but it would be nice to have full invalidation on hash changes when using the hash-based router, to mirror what happens with pathname changes and the pathname router.

I can work around this with something like:

<svelte:window on:hashchange={invalidateAll}/>

but this obviously ends up running some load functions twice.

Reproduction

Open the console when running https://github.com/stephenlrandall/kit-inline-test. Visit http://localhost:5173/?q=svelte#/search, then modify the URL to http://localhost:5173/?q=svelte#/v2/search. Note that in the console, only the search route's load function has been re-run.

Logs

System Info

System:
    OS: macOS 15.2
    CPU: (16) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
    Memory: 401.48 MB / 16.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 20.8.0 - /usr/local/bin/node
    npm: 10.1.0 - /usr/local/bin/npm
    pnpm: 9.15.4 - ~/Library/pnpm/pnpm
  Browsers:
    Chrome: 131.0.6778.265
    Edge: 131.0.2903.147
    Safari: 18.2
  npmPackages:
    @sveltejs/adapter-auto: ^3.3.1 => 3.3.1 
    @sveltejs/adapter-static: ^3.0.8 => 3.0.8 
    @sveltejs/kit: ^2.15.3 => 2.15.3 
    @sveltejs/vite-plugin-svelte: ^4.0.4 => 4.0.4 
    svelte: ^5.18.0 => 5.18.0

Severity

annoyance

Additional Information

No response

[eltigerchino]

Should we trigger a full page reload instead of client-side navigating when the address bar URL is edited so the router behaviours are aligned? cc: @dummdidumm

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

Lines 2393 to 2400 in f451f6c

	} else if (app.hash) {
	// If the user edits the hash via the browser URL bar, it
	// (surprisingly!) mutates `current.url`, allowing us to
	// detect it and trigger a navigation
	if (current.url.hash === location.hash) {
	navigate({ type: 'goto', url: current.url });
	}
	}