ModelRelations type seems to always resolve to the 'never' type

[tony-oldport]

I'm using objection.js 3.0.0 with TypeScript and am trying to utilize the ModelRelations type which the docs say exists to "extract the relation names of the model class". Small example below results in the compilation error on modelRelations: Type 'string' is not assignable to type 'never'. ts(2322)

import { Model, ModelRelations, RelationMappings } from 'objection'
import { UserModel } from './UserModel'

export class TestModel extends Model {
  static tableName = 'test'
  static relationMappings = (): RelationMappings => ({
    user: {
      relation: Model.BelongsToOneRelation,
      modelClass: UserModel,
      join: {
        from: 'test.userId',
        to: 'users.id'
      }
    }
  })
}

type TestModelRelations = ModelRelations<TestModel>

export function testModelClass (): void {
  const modelRelations: TestModelRelations = 'thisvaluedoesntmatter'
  console.log(modelRelations)
}

[lehni]

Related: #2380