Fixed the return type of the Symbol.observable method in the generated .d.ts

[Andarist]

Notice how the return type in the generated .d.ts is currently just any:

export declare function observable<T>(input: Accessor<T>): {
    subscribe(observer: ObservableObserver<T>): {
        unsubscribe(): void;
    };
    [Symbol.observable](): any;
};

You can verify this easily and quickly here: https://unpkg.com/browse/[email protected]/types/reactive/observable.d.ts#L26

It seems that TS can't emit the computed type when it depends on the this outside of the class context and when this refers to an "anonymous type". You can verify this in this TS playground in the ".D.TS" tab. It's a TypeScript issue - I didn't have time to look if it's already reported though, I might do that later.

Note that within the package itself when TS sees the source files the type of this property is correct. It's purely an issue with the declaration emit.

By adding an explicit type declaration for this we enable the correct declaration emit. I confirmed this locally:

export declare function observable<T>(input: Accessor<T>): Observable<T>;

[changeset-bot]

🦋 Changeset detected

Latest commit: 5ac7fea

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

This PR includes changesets to release 2 packages

Name	Type
solid-js	Patch
test-integration	Patch

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[ryansolid]

Thank you.

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• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 88.233%

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Totals
Change from base Build 3993280735:	0.0%
Covered Lines:	1292
Relevant Lines:	1389

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💛 - Coveralls

[Andarist]

You are welcome. I created a TS issue for this here: microsoft/TypeScript#52415