compileParser does not appear to support properties with type field?: Record<string, unknown> via JTDSchemaType.

[elhedran]

What version of Ajv are you using? Does the issue happen if you use the latest version?*

8.12.0

Ajv options object

none

import Ajv, { JTDSchemaType } from 'ajv/dist/jtd'

const ajv = new Ajv()

JSON Schema

export interface IRequest {
    work_type: string,
    meta?: Record<string, unknown>
}

const RequestJDTSchema: JTDSchemaType<IRequest> = {
    properties: {
        work_type: { type: 'string' },
    },
    optionalProperties: {
        meta: { values: {}, nullable: false  },
    }
}

Sample data

{
  "work_type": "example.integration.2',"
  "meta": {
    "picks": [],
    "picks_error": []
  }
}

Your code

NOTE: could not reproduce this in Jest, only in the browser - as such the code is a Lit element that allows interaction to reproduce the issue. I could not work out how to write a standalone automated test to produce the same error.

import { LitElement, html, nothing } from 'lit'
import { customElement, state } from 'lit/decorators.js'
import Ajv, { JTDSchemaType } from 'ajv/dist/jtd'

const ajv = new Ajv()

export interface IRequest {
    work_type: string,
    meta?: Record<string, unknown>
}

const RequestJDTSchema: JTDSchemaType<IRequest> = {
    properties: {
        work_type: { type: 'string' },
    },
    optionalProperties: {
        meta: { values: {}, nullable: false  },
    }
}

export const serializeRequest = ajv.compileSerializer<IRequest>(RequestJDTSchema)

export const parseRequest = ajv.compileParser<IRequest>(RequestJDTSchema)

const jsonTextBad = serializeRequest({
  work_type: 'example.integration.2',
  meta: {
    picks: [],
    picks_error: []
  }
})

const jsonTextGood = serializeRequest({
  work_type: 'example.integration.2',
})

/**
 * An example element.
 *
 * @slot - This element has a slot
 * @csspart button - The button
 */
@customElement('my-element')
export class MyElement extends LitElement {

  @state()
  private errorText: string | undefined
  private request: IRequest | undefined

  render() {
    return html`
      <div>
      <button @click=${this._onBad}>attempt validation of fail case</button>
      <button @click=${this._onGood}>attempt validation of success case</button>
        ${this.errorText
        ? html`<h3>error text</h3>
        <pre>${this.errorText}</pre>`
        : nothing
      }
      ${this.request
        ? html`<h3>request</h3>
        <pre>${JSON.stringify(this.request, null, 2)}</pre>`
        : nothing
      }
      </div>
    `
  }

  private _onGood() {
    this.errorText = undefined
    this.request = parseRequest(jsonTextGood)
    if (!this.request) {
      this.errorText = `${parseRequest.position}: ${parseRequest.message}`
    }
  }

  private _onBad() {
    this.errorText = undefined
    this.request = parseRequest(jsonTextBad)
    if (!this.request) {
      this.errorText = `${parseRequest.position}: ${parseRequest.message}`
    }
  }
}

declare global {
  interface HTMLElementTagNameMap {
    'my-element': MyElement
  }
}

Validation result, data AFTER validation, error messages

74: unexpected end

What results did you expect?

Json was valid (especially given it is created via the compiled serializer)

Are you going to resolve the issue?

I honestly have no idea how this might be resolved. For now I'm working around it in my code by not using compileParser for this particular schema.

[elhedran]

I should also admit I'm new to the JTDSchemaType - so I'm not going to take offense if it turns out the bug is in my code.
The version of the browser I was reproducing this in most recently is Edge: Version 123.0.2420.97 (Official build) (64-bit)

[jasoniangreen]

Hi there, is there any chance you can create a simpler failing example in runkit without using other dependencies (like Lit)? It would simplify understanding and debugging greatly.