Fix for <List> "unused" signal

[maciek50322]

I found that the "signal created when used" is giving wrong values when it's read only later after changes (eg. only in event callback function and none in jsx or other signals or component creation - work correctly if it's used there).

[changeset-bot]

🦋 Changeset detected

Latest commit: 2f06d07

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

This PR includes changesets to release 1 package

Name	Type
@solid-primitives/list	Patch

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[thetarnav]

Please remove changes to the changelog and package json, these are updated automatically by the ci workflow.
Also could you add tests showing when the values were wrong?
mapArray and keyArray are using mapFn.length to check if the index signal is used or not. It would make sense to be consistent with a mapArray alternative.

[maciek50322]

Done.

mapArray and keyArray are using mapFn.length to check if the index signal is used or not.

But for that I argue that you can use arguments that are over what mapFn.length gives...

function mapFn(...args) {
    const value = args[0];
    const index = args[1];
    console.log(`value = ${value}, index = ${index}`);
}

console.log(mapFn.length); // logs: 0
mapFn(1, 2);               // logs: value = 1, index = 2

Probably uncommon but still

[maciek50322]

Ok so I found different way to fix this issue - when creating signal get fresh item index & value instead of one that it was created with. After this change new test passes