breaking: Remove hash from url passed to load

[elliott-with-the-longest-name-on-github]

Fixes #4788. More specifically, this sets the hash of the url passed to load to the empty string, unifying the client- and server-side behavior. See the linked issue for discussion around why this is important.

Please don't delete this checklist! Before submitting the PR, please make sure you do the following:

• It's really useful if your PR references an issue where it is discussed ahead of time. In many cases, features are absent for a reason. For large changes, please create an RFC: https://github.com/sveltejs/rfcs
• This message body should clearly illustrate what problems it solves.
• Ideally, include a test that fails without this PR but passes with it.

Tests

• Run the tests with pnpm test and lint the project with pnpm lint and pnpm check

Changesets

• If your PR makes a change that should be noted in one or more packages' changelogs, generate a changeset by running pnpm changeset and following the prompts. All changesets should be patch until SvelteKit 1.0

[changeset-bot]

🦋 Changeset detected

Latest commit: e78f953

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@sveltejs/kit	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[Rich-Harris]

Nice, thank you! Thinking aloud: I wonder if we should return a Proxy from get url that errors if you try to access url.hash (in bother server and client contexts, I suppose) so that people aren't confused about why it's empty?

[elliott-with-the-longest-name-on-github]

Nice, thank you! Thinking aloud: I wonder if we should return a Proxy from get url that errors if you try to access url.hash (in bother server and client contexts, I suppose) so that people aren't confused about why it's empty?

Wow, I don't know how I've gone this long without seeing a JavaScript Proxy object. That's pretty awesome. Give me five...

[elliott-with-the-longest-name-on-github]

@Rich-Harris

Updated both the behavior and the test. I had to wrap the test in javaScriptEnabled, because obviously load can't run client-side when JavaScript is disabled.

As a sidenote, maybe I'm going crazy, but I may have uncovered a new bug while working on this. In order to separate concerns a bit, I was trying to create a __error.svelte file in src/routes/load. When I created it and caused an error in the load of src/routes/load/url-hash by trying to access url.hash, I could only get src/routes/__error.svelte to render, no matter what I did. You might try replicating on your end to see if it's just something silly I was doing.

[Rich-Harris]

thank you!