Use with fluent-json-schema now requires to call valueOf in ObjectSchema when using Typescript

[Ceres6]

Prerequisites

• [X] I have written a descriptive issue title
• [X] I have searched existing issues to ensure the regression has not already been reported

Last working version

5.1.0

Stopped working in version

5.1.1

Node.js version

18.x

Operating system

macOS

Operating system version (i.e. 20.04, 11.3, 10)

12.3

💥 Regression Report

Typings in Typescript now throw an error when using a fluent-json-schema generated schema as input for envSchema

Steps to Reproduce

In a Typescript file the next block of code reproduces the issue

import envSchema from 'env-schema'
import S from 'fluent-json-schema'

envSchema({
  schema: S.object()
})

Type 'ObjectSchema' is not assignable to type 'AnySchema | UncheckedJSONSchemaType<EnvSchemaData, false> | undefined'.
  Type 'ObjectSchema' is not assignable to type '{ type: "object"; additionalProperties?: boolean | UncheckedJSONSchemaType<unknown, false> | undefined; unevaluatedProperties?: boolean | UncheckedJSONSchemaType<unknown, false> | undefined; ... 7 more ...; maxProperties?: number | undefined; } & { ...; } & { ...; } & { ...; }'.
    Property 'type' is missing in type 'ObjectSchema' but required in type '{ type: "object"; additionalProperties?: boolean | UncheckedJSONSchemaType<unknown, false> | undefined; unevaluatedProperties?: boolean | UncheckedJSONSchemaType<unknown, false> | undefined; ... 7 more ...; maxProperties?: number | undefined; }'.ts(2322)

Nevertheless the following block of code does not throw an error

import envSchema from 'env-schema'
import S from 'fluent-json-schema'

envSchema({
  schema: S.object().valueOf
})

Expected Behavior

As ObjectSchema from fluent-json-schema was removed from typings in #137 it might be solved otherwise or maybe be documented to avoid future confusion

[climba03003]

cc @klaseca

I think I would revert all those changes. It cannot support all the third-party library. Especially, it cannot support fluent-json-schema.

[klaseca]

Under the hood, valueOf is called when passing a schema from fluent-json-schema. How about we remove this code and explicitly call valueOf when passing the schema? It seems to me that if env-schema should work not only with fluent-json-schema, then there should be no code specifically for this library

[climba03003]

How about we remove this code and explicitly call valueOf when passing the schema?

No, it should support out-of-the-box. Since, fastify itself do the same. cc @fastify/core WDYT?

Anyway, it would be a breaking change in either end. If no other fixes come up, the only choice is revert on current release.

[Uzlopak]

I would also revert the problematic PR and maybe add fluent-json-schema as dependency or as peerDependency

[klaseca]

Perhaps the best solution in this situation would be to return the object type for the schema. At the same time, leave the re-import of the JSONSchemaType type from the ajv package. In this case, we will return the previous fully working state and leave the option to declare a type-checked schema

[mcollina]

Fastify can support fluent-json-schema without the need of it being a dependency. Take a look how it's done there.

[jessekrubin]

FWIW: Something similar is going on with types here when using with typebox