Bulk Edit causes deletion of array fields

[thekiwi]

Describe the Bug

It seems that with 3.0.0 and newer (I've tried up to 3.1.0 but I haven't tested older versions) when using bulk edit to update one field causes Payload to delete another field of type array.

Link to the code that reproduces this issue

https://github.com/thekiwi/payload-bulk-edit-bug

Reproduction Steps

1. Start the reproduction repo, pointing at a PostgreSQL database (I used 16.3)

2. Log into the Admin panel (first creating a user, if necessary)

3. Create a new Thing, leave 'enabled' unchecked, but add an entry to the 'foos' array
   

4. View the list of things, you should see 1 Foos for the new thing

5. Check the things_foos collection in the DB and observe there is now 1 record.
   

6. Check the thing you just created and click "Edit" to start bulk editing

7. Toggle the 'enabled' field to true for the thing you just created
   

8. Click "Save"

9. Return to the list of things, you should see 0 Foos for the thing you just edited
   

10. Check the things_foos collection in the DB and observe there are now 0 records
    

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

db-postgres, area: core

Environment Info

Binaries:
  Node: 20.16.0
  npm: 10.8.1
  Yarn: 1.22.22
  pnpm: 9.7.0
Relevant Packages:
  payload: 3.1.0
  next: 15.0.0
  @payloadcms/db-postgres: 3.1.0
  @payloadcms/email-nodemailer: 3.1.0
  @payloadcms/graphql: 3.1.0
  @payloadcms/next/utilities: 3.1.0
  @payloadcms/payload-cloud: 3.1.0
  @payloadcms/richtext-lexical: 3.1.0
  @payloadcms/translations: 3.1.0
  @payloadcms/ui/shared: 3.1.0
  react: 19.0.0-rc-65a56d0e-20241020
  react-dom: 19.0.0-rc-65a56d0e-20241020
Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 24.0.0: Tue Sep 24 23:39:07 PDT 2024; root:xnu-11215.1.12~1/RELEASE_ARM64_T6000
  Available memory (MB): 16384
  Available CPU cores: 8

[akhrarovsaid]

I've reproduced this in the Payload monorepo pre 3.2 release using both db-postgres and db-mongodb. The odd thing is that it happens 4 / 5 times with the fifth time working as expected. Will double check if it's still happening.