[feat] invalidate with predicate

[icalvin102]

Closes #4540

Problem

The current implementation of invalidate is quite limiting because the provided argument has to match the URL of the fetched resource exactly. It's not possible to invalidate resources that match a certain pattern. (Take a look at #4540 for more detailed problem description)

Solution

Extend invalidate to take a predicate function as argument (similar to Array.prototype.some).
The predicate is run for each item of dependencies and will cause a rerun of load if true is returned.

Signature:

function invalidate(href: string): Promise<void>;
function invalidate(predicate: (dep: string) => boolean): Promise<void>;

Example usage:

<script context="module">
export async function load({fetch, url}) {
  const response = await fetch(`/collections${url.search}`);
  const data = await response.json();
  
  return { props: { data }};
}
</script>
<script>
  import { invalidate } from '$app/navigation';
  const isCollectionURL = (dep) => dep.includes('/collections');
</script>

<button on:click={() => invalidate(isCollectionURL)}>Reload collection</button>

This makes the invalidate function far more useful IMO and would not break how it's currently used.

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Latest commit: 3dadac6

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[icalvin102]

I have included a test. However the test fails because playwright is unable to serialize the predicate function and throws a Unexpeced value error in

kit/packages/kit/test/utils.js

Line 27 in f445802

invalidate: (url) => page.evaluate((/** @type {string} */ url) => invalidate(url), url),

This is a problem with playwright and not with the actual feature. I don't have much experience with playright and am not sure how to solve this. It would be nice if someone could take a look at this or guide me in the right direction.

[Rich-Harris]

thank you!