Support array of scalars in structured output

diff/diff_test.go

@@ -602,6 +602,23 @@ spec:
       containers:
       - name: app
         image: demo:v1
+      affinity:
+        nodeAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+            nodeSelectorTerms:
+            - matchExpressions:
+              - key: node-type
+                operator: In
+                values:
+                - standard
+      priorities:
+      - 1
+      booleanArrayField:
+      - true
+      multiTypeField:
+      - 3
+      - true
+      - "string"
 `
 	newManifest := `
 apiVersion: apps/v1
@@ -616,6 +633,23 @@ spec:
       containers:
       - name: app
         image: demo:v2
+      affinity:
+        nodeAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+            nodeSelectorTerms:
+            - matchExpressions:
+              - key: node-type
+                operator: In
+                values:
+                - dedicated
+      priorities:
+      - 2
+      booleanArrayField:
+      - false
+      multiTypeField:
+      - false
+      - "new-string"
+      - 2
 `
 	oldIndex := manifest.Parse([]byte(oldManifest), "prod", true)
 	newIndex := manifest.Parse([]byte(newManifest), "prod", true)
@@ -633,7 +667,7 @@ spec:
 	require.Equal(t, "Deployment", entry.Kind)
 	require.Equal(t, "prod", entry.Namespace)
 	require.Equal(t, "web", entry.Name)
-	require.Len(t, entry.Changes, 2)
+	require.Len(t, entry.Changes, 8)
 	replicasChange, ok := findChange(entry.Changes, "spec", "replicas")
 	require.True(t, ok)
 	require.InDelta(t, float64(2), replicasChange.OldValue, 0.001)
@@ -643,6 +677,36 @@ spec:
 	require.True(t, ok)
 	require.Equal(t, "demo:v1", imageChange.OldValue)
 	require.Equal(t, "demo:v2", imageChange.NewValue)
+
+	affinityChange, ok := findChange(entry.Changes, "spec.template.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution.nodeSelectorTerms[0].matchExpressions[0].values", "0")
+	require.True(t, ok)
+	require.Equal(t, "standard", affinityChange.OldValue)
+	require.Equal(t, "dedicated", affinityChange.NewValue)
+
+	priorityChange, ok := findChange(entry.Changes, "spec.template.spec.priorities", "0")
+	require.True(t, ok)
+	require.InDelta(t, float64(1), priorityChange.OldValue, 0.001)
+	require.InDelta(t, float64(2), priorityChange.NewValue, 0.001)
+
+	booleanArrayFieldChange, ok := findChange(entry.Changes, "spec.template.spec.booleanArrayField", "0")
+	require.True(t, ok)
+	require.Equal(t, true, booleanArrayFieldChange.OldValue)
+	require.Equal(t, false, booleanArrayFieldChange.NewValue)
+
+	multiTypeFieldChange0, ok := findChange(entry.Changes, "spec.template.spec.multiTypeField", "0")
+	require.True(t, ok)
+	require.InDelta(t, float64(3), multiTypeFieldChange0.OldValue, 0.001)
+	require.Equal(t, false, multiTypeFieldChange0.NewValue)
+
+	multiTypeFieldChange1, ok := findChange(entry.Changes, "spec.template.spec.multiTypeField", "1")
+	require.True(t, ok)
+	require.Equal(t, true, multiTypeFieldChange1.OldValue)
+	require.Equal(t, "new-string", multiTypeFieldChange1.NewValue)
+
+	multiTypeFieldChange2, ok := findChange(entry.Changes, "spec.template.spec.multiTypeField", "2")
+	require.True(t, ok)
+	require.Equal(t, "string", multiTypeFieldChange2.OldValue)
+	require.InDelta(t, float64(2), multiTypeFieldChange2.NewValue, 0.001)
 }
 
 func TestStructuredOutputAddAndRemove(t *testing.T) {
@@ -654,7 +718,20 @@ kind: Job
 metadata:
   name: migrate
   namespace: ops
-spec: {}
+spec:
+  restartPolicy: "Never"
+  containers:
+  - name: app
+    image: demo:v1
+    affinity:
+      nodeAffinity:
+        requiredDuringSchedulingIgnoredDuringExecution:
+          nodeSelectorTerms:
+          - matchExpressions:
+            - key: node-type
+              operator: In
+              values:
+              - standard
 `
 	newIndex := manifest.Parse([]byte(newManifest), "ops", true)
 
@@ -665,6 +742,7 @@ spec: {}
 	var entries []StructuredEntry
 	require.NoError(t, json.Unmarshal(buf.Bytes(), &entries))
 	require.Len(t, entries, 1)
+
 	require.Equal(t, "ADD", entries[0].ChangeType)
 	require.True(t, entries[0].ResourceStatus.NewExists)
 	require.False(t, entries[0].ResourceStatus.OldExists)

diff/structured.go

@@ -271,6 +271,18 @@ func diffArrayNodes(changes *[]FieldChange, tokens []string, oldNode, newNode in
 			if reflect.DeepEqual(oldVal, newVal) {
 				continue
 			}
+			// createNodePatch only supports JSON objects; handle scalar values directly
+			if isScalarValue(oldVal) && isScalarValue(newVal) {
+				path, field := splitTokens(next)
+				*changes = append(*changes, FieldChange{
+					Path:     path,
+					Field:    field,
+					Change:   "replace",
+					OldValue: oldVal,
+					NewValue: newVal,
+				})
+				continue
+			}
 			subPatch, err := createNodePatch(oldVal, newVal)
 			if err != nil {
 				return err
@@ -311,6 +323,18 @@ func diffArrayNodes(changes *[]FieldChange, tokens []string, oldNode, newNode in
 	return nil
 }
 
+func isScalarValue(value interface{}) bool {
+	switch value.(type) {
+	case string, bool,
+		float32, float64,
+		int, int8, int16, int32, int64,
+		uint, uint8, uint16, uint32, uint64:
+		return true
+	default:
+		return false
+	}
+}
+
 func createNodePatch(oldNode, newNode interface{}) (interface{}, error) {
 	oldJSON, err := json.Marshal(oldNode)
 	if err != nil {