add tests for sorting objects

On-behalf-of: @SAP christoph.mewes@sap.com

Author: xrstf

internal/manifest/sort_test.go

@@ -0,0 +1,103 @@
+/*
+Copyright 2026 The kcp Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package manifest
+
+import (
+	"testing"
+
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+)
+
+func TestSortObjectsByHierarchy(t *testing.T) {
+	crd := newUnstructured("apiextensions.k8s.io/v1", "CustomResourceDefinition", "test-crd")
+	apiExport := newUnstructured("apis.kcp.io/v1alpha1", "APIExport", "test-export")
+	apiBinding := newUnstructured("apis.kcp.io/v1alpha1", "APIBinding", "test-binding")
+	namespace := newUnstructured("v1", "Namespace", "test-ns")
+	configMap := newUnstructured("v1", "ConfigMap", "test-cm")
+	deployment := newUnstructured("apps/v1", "Deployment", "test-deploy")
+	service := newUnstructured("v1", "Service", "test-svc")
+
+	testcases := []struct {
+		name     string
+		input    []*unstructured.Unstructured
+		expected []*unstructured.Unstructured
+	}{
+		{
+			name:     "empty input",
+			input:    []*unstructured.Unstructured{},
+			expected: []*unstructured.Unstructured{},
+		},
+		{
+			name:     "single object",
+			input:    []*unstructured.Unstructured{configMap},
+			expected: []*unstructured.Unstructured{configMap},
+		},
+		{
+			name:     "already sorted",
+			input:    []*unstructured.Unstructured{crd, apiExport, apiBinding, namespace, configMap},
+			expected: []*unstructured.Unstructured{crd, apiExport, apiBinding, namespace, configMap},
+		},
+		{
+			name:     "reverse order",
+			input:    []*unstructured.Unstructured{configMap, namespace, apiBinding, apiExport, crd},
+			expected: []*unstructured.Unstructured{crd, apiExport, apiBinding, namespace, configMap},
+		},
+		{
+			name:     "mixed order",
+			input:    []*unstructured.Unstructured{namespace, configMap, crd, deployment, apiBinding, apiExport},
+			expected: []*unstructured.Unstructured{crd, apiExport, apiBinding, namespace, configMap, deployment},
+		},
+		{
+			name:     "multiple objects of same kind",
+			input:    []*unstructured.Unstructured{configMap, crd, configMap, crd},
+			expected: []*unstructured.Unstructured{crd, crd, configMap, configMap},
+		},
+		{
+			name:     "only regular objects",
+			input:    []*unstructured.Unstructured{service, configMap, deployment},
+			expected: []*unstructured.Unstructured{service, configMap, deployment},
+		},
+	}
+
+	for _, tt := range testcases {
+		t.Run(tt.name, func(t *testing.T) {
+			SortObjectsByHierarchy(tt.input)
+
+			if len(tt.input) != len(tt.expected) {
+				t.Fatalf("Expected %d objects, got %d", len(tt.expected), len(tt.input))
+			}
+
+			for i, obj := range tt.input {
+				if obj != tt.expected[i] {
+					t.Fatalf("At index %d: expected %s, got %s", i, tt.expected[i].GetKind(), obj.GetKind())
+				}
+			}
+		})
+	}
+}
+
+func newUnstructured(apiVersion, kind, name string) *unstructured.Unstructured {
+	return &unstructured.Unstructured{
+		Object: map[string]any{
+			"apiVersion": apiVersion,
+			"kind":       kind,
+			"metadata": map[string]any{
+				"name": name,
+			},
+		},
+	}
+}