Support circular schema definitions

[Stefano31]

First of all, great job.

I have tried to use this library but in a test case I have found a problem with the circular schema.

To Reproduce
Use any circular schema, here an example:

// file tree.oas.ts
// Open API Specification
export default {
  openapi: "3.0.3",
  info: {
    version: "1",
    title: "Tree - OpenAPI 3.0",
    description:
      "This is a sample of tree",
    termsOfService: "http://swagger.io/terms/",
  },
  paths: {
    "/tree": {
      get: {
        tags: ["tree"],
        summary: "Get tree",
        description: "",
        operationId: "getTree",
        responses: {
          "200": {
            description: "successful operation",
            content: {
              "application/json": {
                schema: {
                  $ref: "#/components/schemas/Node",
                },
              },
            },
          },
          "404": {
            description: "Tree not found",
          },
        },
      },
    },
  },
  components: {
    schemas: {
      Node: {
        type: "object",
        properties: {
          number: {
            type: "integer",
            format: "int64",
            example: 10,
          },
          child: {
            $ref: "#/components/schemas/Node",
          },
        },
      },
    },
  },
} as const;

// file client.ts
import { createClient, Mutable } from 'fets'
import treeOAS from './tree.oas'
 
const client = createClient<Mutable<typeof treeOAS>>()

const response = await client['/tree'].get() // <--- HERE THERE IS AN ERROR TS2615 (circular reference for field "child")

const body = await response.json()

console.log(body)

Expected behavior

Honestly, I don't know how to works deeply this library and I'm trying to understand, but I think that should be there a flag that avoids these scenarios with circular reference

Environment:

• package-name...: fets
• NodeJS: 18

[ardatan]

Fixed in #335 ! Thanks for the feedback!