LocalBusiness type does not recognise `@type: 'LocalBusiness'` about schema-dts

[Eyas]

The error is misleading, but TypeScript is being tripped up by "@context" and excess property checks.

tl;dr: If this is a top-level object, change the type to WithContext<LocalBusiness>. Or otherwise drop @context (you only need a context at the topmost JSON-LD object or graph).

Explanation

TypeScript generally has excess property checks to make sure you're not misspelling something, e.g.:

type A = { x?: string; y?: string; }
const thing: A = {z: string};

while technically thing is a subtype of A, this is often a sign of mistake, so TS will warn that z is wrong.

In schema-dts, @context is only supplied in WithContext<T>. Unfortunately, instead of straightforwardly complaining about @context not being found, TS does it in a very weird way when there's a discriminated union.

[Eyas]

I think we can close this, but let me know if you have any issues here!

[a-ogilvie]

@Eyas Thank you!! It feels great to have some type safety on my structured data. Thanks to this library, I found a small error in the existing data.

I wonder if the WithContext trick could be documented somewhere. I tried Googling my way out of the problem, but I couldn't find any documentation on this error.

[Eyas]

That's a good point! WithContext is briefly mentioned in the "Root Context" section of the readme (right under usage), but if you're troubleshooting your failure (especially cryptic sounding errors from TS) then you'll have trouble finding WithContext as the answer.

Honestly I'm open to feedback. I agree additional documentation is helpful, but I'm not sure what/where. You can always open a PR and fix/add docs as well!