add test case

kustomize/commands/edit/fix/convert_test.go

@@ -8,6 +8,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+
 	testutils_test "sigs.k8s.io/kustomize/kustomize/v5/commands/internal/testutils"
 	"sigs.k8s.io/kustomize/kyaml/filesys"
 )
@@ -1143,3 +1144,76 @@ metadata:
     a.b.c: SOME_SECRET_NAME_PLACEHOLDER
 `, string(content))
 }
+
+func TestFixVarsWithPatch(t *testing.T) {
+	kustomization := []byte(`
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+
+patchesStrategicMerge:
+  - patch.yaml
+
+vars:
+  - name: CERTIFICATE_NAMESPACE
+    objref:
+      name: system
+    fieldref:
+      fieldpath: metadata.namespace
+`)
+	patch := []byte(`
+apiVersion: apps/v1
+kapiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: controller-manager
+  namespace: system
+spec:
+  template:
+    spec:
+      containers:
+        - name: $(CERTIFICATE_NAMESPACE)
+`)
+
+	fSys := filesys.MakeFsInMemory()
+	testutils_test.WriteTestKustomizationWith(fSys, kustomization)
+	fSys.WriteFile("patch.yaml", patch)
+	cmd := NewCmdFix(fSys, os.Stdout)
+	assert.NoError(t, cmd.Flags().Set("vars", "true"))
+	assert.NoError(t, cmd.RunE(cmd, nil))
+	content, err := testutils_test.ReadTestKustomization(fSys)
+	assert.NoError(t, err)
+
+	assert.Equal(t, `
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+
+
+patches:
+- path: patch.yaml
+replacements:
+- source:
+    fieldPath: metadata.namespace
+    name: system
+  targets:
+  - fieldPaths:
+    - spec.template.spec.containers.0.name
+    select:
+      namespace: system
+`, string(content))
+
+	content, err = fSys.ReadFile("patch.yaml")
+	assert.NoError(t, err)
+	assert.Equal(t, `
+apiVersion: apps/v1
+kapiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: controller-manager
+  namespace: system
+spec:
+  template:
+    spec:
+      containers:
+        - name: CERTIFICATE_NAMESPACE_PLACEHOLDER
+`, string(content))
+}