withoutEnlargement doesn't work when height is undefined in upload.imageSizes

[Zhousiru]

Describe the Bug

I want to create image sizes like 1000w, 2000w, etc., to use with srcset. I hope that when the original image size is smaller than the corresponding thumbnail width, the thumbnail won't be generated (this seems to be the behavior when withoutEnlargement is undefined)

Also, I want to keep the original image's aspect ratio. After setting the height to undefined, I encountered an issue where, regardless of the image's width, it always enlarges the image and generates thumbnails in all sizes

I tried setting withoutEnlargement to true, but this led to the creation of duplicate-sized images, which does not meet my requirements 🥲

Here is my Media.ts configuration:

import type { CollectionConfig } from 'payload'

export const Media: CollectionConfig = {
  slug: 'media',
  access: {
    read: () => true,
  },
  fields: [
    {
      name: 'alt',
      type: 'text',
      required: true,
    },
  ],
  upload: {
    imageSizes: [
      {
        name: `100w`,
        width: 100,
        height: undefined,
        withoutEnlargement: undefined,
      },
      {
        name: `4000w`,
        width: 4000,
        height: undefined,
        withoutEnlargement: undefined,
      },
    ],
    adminThumbnail: '100w',
  },
}

And reproduction repo here

Link to the code that reproduces this issue

https://github.com/Zhousiru/payload-repro-2

Reproduction Steps

1. Launch the reproduction app
2. Upload the test-image.jpg (600x400, available in reproduction repo) to the media collection
3. The image was scaled to 4000x2667

And here is the screen recording:

repro.mp4

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

area: core

Environment Info

Binaries:
  Node: 20.16.0
  npm: 10.8.1
  Yarn: N/A
  pnpm: 9.15.0
Relevant Packages:
  payload: 3.7.0
  next: 15.1.0
  @payloadcms/email-nodemailer: 3.7.0
  @payloadcms/graphql: 3.7.0
  @payloadcms/next/utilities: 3.7.0
  @payloadcms/payload-cloud: 3.7.0
  @payloadcms/richtext-lexical: 3.7.0
  @payloadcms/translations: 3.7.0
  @payloadcms/ui/shared: 3.7.0
  react: 19.0.0
  react-dom: 19.0.0
Operating System:
  Platform: linux
  Arch: x64
  Version: #1 SMP PREEMPT_DYNAMIC Debian 6.11.9-1 (2024-11-17)
  Available memory (MB): 15998
  Available CPU cores: 12

[Zhousiru]

Hi there, I provided a possible fix in #10078 😉