[RFC] Throw an EntityNotFoundError when loading a non-existent singleton Entity?

[GregBrimble]

If you attempt to load a non-singleton Entity which does not exist, an EntityNotFoundError is thrown:

@Entity({ datastore })
class ComplexEntity {

    @Column({ isPrimary: true })
    public id: string

    constructor(id: string) {
        this.id = id
    }
}

const complexRepository = getRepository(ComplexEntity)

const complexInstance = new ComplexEntity('12345')
await complexRepository.save(complexInstance)

await complexRepository.load('12345')  // returns a new ComplexEntity instance

await complexRepository.load('99999')  // throws EntityNotFoundError

This behaviour is not found with singleton Entities:

@Entity({ datastore })
class SingletonEntity {
    // ...
}

const singletonRepository = getRepository(SingletonEntity)

const singletonInstance = new SingletonEntity()

await singletonRepository.load()  // returns a new SingletonEntity instance <--

await singletonRepository.save(singletonInstance)
await singletonRepository.load()  // returns a new SingletonEntity instance

Should the indicated line (<--) throw an EntityNotFoundError? If so, why? If not, why not?

[GregBrimble]

See #45 for the non-singleton Entity implementation.