ArgoCD UI breaks when spec.template.spec.sources are empty

[seos-vcbs]

Checklist:

• [ x] I've searched in the docs and FAQ for my answer: https://bit.ly/argocd-faq.
• [ x] I've included steps to reproduce the bug.
• [ x] I've pasted the output of argocd version.

Describe the bug ArgoCD UI breaks when spec.template.spec.sources are empty

To Reproduce

kind: ApplicationSet
metadata:
  name: foo-backend-support-services
  namespace: bar
  labels:
    argocd.baz.tech/name: foo-backend-support-services
  annotations:
    argocd.paramount.tech/description: |-
      ApplicationSet for 'foo-backend-support-services'.
    k8s.baz.tech/technical-owner: 'foo@example.com'
spec:
  generators:
  - list:
      elements:
      - id: foo-use1-dev
        env: dev
        region: use1
        cluster: foo.dev.aws.viacbs.tech
  template:
    metadata:
      name: '{{id}}'
      namespace: bar
      finalizers:
        - resources-finalizer.argocd.argoproj.io
    spec:
      project: abcd
      syncPolicy:
        automated:
          prune: true
          selfHeal: true
      sources:
      destination:
        name: '{{cluster}}'
        namespace: bar

Expected behavior

ArgoCD UI for my dev app-of-apps project breaks. I am attaching the screenshot.

Screenshots

Version

v2.12.4+27d1e64

Logs

[crenshaw-dev]

Try 2.12.6, there were two PRs related to this.

[seos-vcbs]

Thank you very much for the quick response. @crenshaw-dev

[dee-kryvenko]

We just updated to 2.12.7 @crenshaw-dev, and we can see that there is now a validation that prevents this sort of sync, but still the fact that the intent in git was in the ApplicationSet even if was not synced - it breaks the UI on the list of apps screen.