`add` works similarly `replace`

[tebaly]

What happened?

- op: add
  path: /spec
  value: {}

Such a patch leads to replacement /spec with a {} object

What did you expect to happen?

Should be added if the path is missing. Don't replace an existing value

How can we reproduce it (as minimally and precisely as possible)?

kind: HorizontalPodAutoscaler
metadata:
  name: api
spec: 
  minReplicas: 1
---
kind: HorizontalPodAutoscaler
metadata:
  name: api
  labels: 
    add.spec: true

Expected output

kind: HorizontalPodAutoscaler
metadata:
  name: api
spec: 
  minReplicas: 1
---
kind: HorizontalPodAutoscaler
metadata:
  name: api
  labels: 
    add.spec: true
spec: {}

Actual output

kind: HorizontalPodAutoscaler
metadata:
  name: api
spec: {}
---
kind: HorizontalPodAutoscaler
metadata:
  name: api
  labels: 
    add.spec: true
spec: {}

Kustomize version

v5.3.0

Operating system

Linux

[k8s-ci-robot]

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[tebaly]

https://datatracker.ietf.org/doc/html/rfc6902#section-4.1