kustomize: strategicMergePatch clobbers patched arrays

[joelanford]

What broke? What's expected?

When I enabled the manager_metrics_patch.yaml in config/default/kustomization.yaml, it wiped out the arguments that I had setup in the config/manager/manager.yaml.

Reproducing this issue

Initialize project and build manifests with and without metrics patch commented:

kubebuilder init --plugins go/v4 --domain example.org --owner "Your name" --repo example.org/test-project
make kustomize && bin/kustomize-v5.3.0 build config/default > default.yaml
sed -i 's/#- path: manager_metrics_patch.yaml/- path: manager_metrics_patch.yaml/' config/default/kustomization.yaml
make kustomize && bin/kustomize-v5.3.0 build config/default > metrics-patch.yaml

Diff the manifests:

diff default.yaml metrics-patch.yaml
151,153c151
<         - --leader-elect
<         - --health-probe-bind-address=:8081
<         - --metrics-bind-address=0
---
>         - --metrics-bind-address=0.0.0.0:8080

KubeBuilder (CLI) Version

v3.15.0

PROJECT version

v3

Plugin versions

go.kubebuilder.io/v4

Other versions

No response

Extra Labels

No response

[camilamacedo86]

Hi @joelanford,

For now I think the best is we ensure that it is as it was before: #3937
I tracked an issue for we analyse the suggestion to use Pod instead: #3936