FindOptionsRelations when @OneToMany

[Stephen2]

Issue Description

Have an Entity

User {
  @OneToMany(() => Child, ({ parent }) => parent, { cascade: true })
  children!: readonly Child[] | undefined;
}

Have an Entity

Child {
  @ManyToOne(() => User, ({ children }) => children, { nullable: false, onDelete: "CASCADE" })
  parent!: User | undefined;

  @OneToMany(() => Claim, ({ child }) => child, { cascade: true })
  claims!: readonly Claim[] | undefined;
}

Try and select user+children+claims:

    const user = await baseRepository.findOne({
      relations: {
        children: {
          claims: true,
          journalEntries: true,
        },
      },
      where: {
        id,
      },
    });

Get compile time error:

Type '{ children: { claims: true; journalEntries: true; }; }' is not assignable to type 'FindOptionsRelationByString | FindOptionsRelations<User>'.
  Types of property 'children' are incompatible.
    Type '{ claims: true; journalEntries: true; }' is not assignable to type 'boolean | readonly (boolean | FindOptionsRelations<Child> | undefined)[] | undefined'.
      Object literal may only specify known properties, and 'claims' does not exist in type 'readonly (boolean | FindOptionsRelations<Child> | undefined)[]'.ts(2322)

Such that you have to write code:

      relations: {
        children: [
          {
            claims: true,
            journalEntries: true,
          },
        ],
      },

Note the addition of [] which doesn't make sense when writing code.

Causes runtime error: EntityPropertyNotFoundError: Property "0" was not found in "Child". Make sure your query is correct.

Can workaround with ts-expect-error:

      relations: {
        children: {
          // @ts-expect-error TypeORM types want this to be an [] becuase it's silly
          // That causes runtime error: EntityPropertyNotFoundError: Property "0" was not found in "Child". Make sure your query is correct.
          claims: true,
          journalEntries: true,
        },
      },

Expected Behavior

FindOptionsRelations types to be modified for this nested case

Actual Behavior

Types are wrong, error messages shown above

Steps to Reproduce

As above

My Environment

Dependency	Version
Operating System
Node.js version	16.15.1
Typescript version	4.8.2
TypeORM version	0.3.9

Are you willing to resolve this issue by submitting a Pull Request?

• ✅ No, I don’t have the time and I’m okay to wait for the community / maintainers to resolve this issue.

[iJhefe]

it's occurs because your property type is "readonly" and the FindOptionsRelationsProperty interface does not handle this.
May it be fixed just adding to FindOptionsRelationsProperty

Property extends Readonly<Array<infer I>> ? FindOptionsRelationsProperty<NonNullable<I>> | boolean

[Stephen2]

Awesome thank you for the find @iJhefe !