feat: support JSON Schema as input for a Type

[TizzySaurus]

Closes #729.

What

This PR adds @ark/jsonschema, which is a library enabling users to convert a valid JSON Schema schema into an ArkType type.

API

Below is a basic sample-use of @ark/jsonschema:

import { parseJsonSchema } from "@ark/jsonschema"

const type = parseJsonSchema({type: "string"})
// ^? 
// NB: `type` is correctly inferred as `Type<string>`, and can now be used as-per any other ArkType type

Remaining Work Before Merging

• For some reason parseJsonSchema({type: "array", items: {type: "string"}}) raises TypeError: this.Schema1Apply is not a function despite working against an earlier ArkType version (probably a bug in ArkType that I've not yet delved into to properly give details).

• Similar to above, const t = parseJsonSchema({oneOf: [{type: "string"}, {type: "number"}]}) raises TypeError: this.CompositionKeywords1Apply is not a function:
  

• Tests are only partially implemented.

  • I wasn't entirely confident on what should/shouldn't be tested, and where things should/shouldn't be tested, so am waiting on feedback for this before finishing the tests.
    • For example, I have tests for {type: "string", "maxLength": 5} and {type: "string", "pattern": "es"}, but not {type: "string", "maxLength": 5, "pattern": "es"}. Is it worth having tests for the various "permutations"? I think this is perhaps overly excessive?
  • All test files also give this linting errors stating it can't find the @ark/jsonschema package:
    

• Haven't yet properly filled out ark/jsonschema/CHANGELOG.md.

Known Limitations (things I didn't implement from JSON Schema spec)

• No type inference (this was removed in 07a5215)
• No support for JSON Schema dependencies keyword on objects.
• No support for JSON Schema if/else/then.
  • Sort of not required, since you can write the same (admittedly more verbosely) by combining any/oneOf/allOf/not.
• multipleOf on numbers only supports integer divisors, due to ArkType only supporting integer divisors.

[TizzySaurus]

Type inference removed in 07a5215. Maybe at some point in the future it can be re-added, but agree that for now we should focus on getting a version without inference merged.

I still need to address the rest of your comments but I've run out of time for now so will have to wait. Work's been super hectic recently so haven't been able to work on this as much as I would've liked 😅

[gabrielgrant]

@ssalbdivad are you open to lifting ArkType's restriction on divisors being non-integers? Or, if not/as an interim solution, it seems this could be added as a custom narrow constraint?

[ssalbdivad]

You can add whatever arbitrary validation you want in a narrow, but the reason we don't support this is because there isn't a straightforward way to test float divisibility without complex + potentially fallible string math.

@TizzySaurus was actually working on an implementation but it doesn't make sense to add a dependency or implement that much custom logic for such a niche case.

For rational values like 0.1, you could testing something like (n: number) => (n * 10) % 1 === 0. Outside that though, things tend to get scary so be careful.

[TizzySaurus]

Yes, I looked into this and it's just not feasible to do floating point division in NodeJS: