join field - hasamany false does not change the ts type definition

[altarapid]

Describe the Bug

When I add a join field to my collection it is automatically an HasMany field.

However, If I set it to hasmany:false then it does not update the type accordingly.
{ name: 'order', label: { en: 'Order', }, type: 'join', collection: 'orders', hasMany: false, on: 'bookedResources', },

order?: { docs?: (string | Order)[]; hasNextPage?: boolean; totalDocs?: number; };

There should not be an array type here imo.

Link to the code that reproduces this issue

https://payloadcms.com/docs/fields/join

Reproduction Steps

Create a field "join" and set has many to false - it does no update the ts type

Which area(s) are affected? (Select all that apply)

area: core, Not sure

Environment Info

> cross-env NODE_OPTIONS=--no-deprecation payload info

! The local project doesn't define a 'packageManager' field. Corepack will now add one referencing [email protected]+sha512.a6b2b721bba3d67d4aff083df04dad64c399707841b7acf00f6b133b7ac24255f2652fa22ae3534329dc6180534e98d1743203140556e2bb3137e.
! For more details about this field, consult the documentation at https://nodejs.org/api/packages.html#packagemanager

 ERROR  This project is configured to use yarn
For help, run: pnpm help

Binaries:
  Node: 18.20.4
  npm: 10.9.2
  Yarn: 1.22.22
  pnpm: N/A
Relevant Packages:
  payload: 3.48.0
  next: 15.3.3
  @payloadcms/db-mongodb: 3.48.0
  @payloadcms/email-nodemailer: 3.48.0
  @payloadcms/graphql: 3.45.0
  @payloadcms/live-preview: 3.45.0
  @payloadcms/live-preview-react: 3.48.0
  @payloadcms/next/utilities: 3.48.0
  @payloadcms/payload-cloud: 3.48.0
  @payloadcms/plugin-form-builder: 3.48.0
  @payloadcms/plugin-nested-docs: 3.48.0
  @payloadcms/plugin-redirects: 3.48.0
  @payloadcms/plugin-search: 3.48.0
  @payloadcms/plugin-seo: 3.48.0
  @payloadcms/richtext-lexical: 3.48.0
  @payloadcms/translations: 3.48.0
  @payloadcms/ui/shared: 3.48.0
  react: 19.1.0
  react-dom: 19.1.0
Operating System:
  Platform: linux
  Arch: x64
  Version: #27~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Tue Jul 22 17:38:49 UTC 2
  Available memory (MB): 31211
  Available CPU cores: 32

[github-actions[bot]]

Please add a reproduction in order for us to be able to investigate.

Depending on the quality of reproduction steps, this issue may be closed if no reproduction is provided.

Why was this issue marked with the invalid-reproduction label?

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Useful Resources

• Reproduction Guide
• Contributing to Payload

[DanRibbens]

When I initially worked on adding the join field I had some type issues when I tried to define hasMany to be hasMany: never. It is something we can revisit or implement as a full feature. For this reason I've converted this to a discussion since we use those for feature requests instead of issues.

[Illuday]

I agree, it feels strange to get a docs array when setting up a one-to-one relationship. What’s more, there’s no safeguard when adding multiple docs, it’s still allowed, even if the join field is defined with hasMany: false.

In the end, hasMany: false doesn’t seem to have any effect on a join field.