Protect ProviderConfigs while managed resources terminate

pkg/meta/meta.go

@@ -205,6 +205,25 @@ func FinalizerExists(o metav1.Object, finalizer string) bool {
 	return slices.Contains(f, finalizer)
 }
 
+// NonGCFinalizers returns the supplied object's finalizers, excluding the two
+// the Kubernetes garbage collector uses to implement deletion propagation -
+// foregroundDeletion and orphan. Neither belongs to a controller, and neither
+// makes a claim on an external system.
+func NonGCFinalizers(o metav1.Object) []string {
+	f := o.GetFinalizers()
+	out := make([]string, 0, len(f))
+
+	for _, e := range f {
+		if e == metav1.FinalizerDeleteDependents || e == metav1.FinalizerOrphanDependents {
+			continue
+		}
+
+		out = append(out, e)
+	}
+
+	return out
+}
+
 // AddLabels to the supplied object.
 func AddLabels(o metav1.Object, labels map[string]string) {
 	l := o.GetLabels()

pkg/meta/meta_test.go

@@ -605,6 +605,50 @@ func TestFinalizerExists(t *testing.T) {
 	}
 }
 
+func TestNonGCFinalizers(t *testing.T) {
+	type args struct {
+		o metav1.Object
+	}
+
+	cases := map[string]struct {
+		reason string
+		args   args
+		want   []string
+	}{
+		"NoFinalizers": {
+			reason: "An object without finalizers has no finalizers after garbage collector finalizers are excluded.",
+			args:   args{o: &corev1.Pod{}},
+			want:   []string{},
+		},
+		"OnlyGCFinalizers": {
+			reason: "The foregroundDeletion and orphan finalizers must both be excluded.",
+			args: args{o: &corev1.Pod{ObjectMeta: metav1.ObjectMeta{Finalizers: []string{
+				metav1.FinalizerDeleteDependents,
+				metav1.FinalizerOrphanDependents,
+			}}}},
+			want: []string{},
+		},
+		"KeepsControllerFinalizers": {
+			reason: "Finalizers that don't belong to the garbage collector must be kept, in order.",
+			args: args{o: &corev1.Pod{ObjectMeta: metav1.ObjectMeta{Finalizers: []string{
+				metav1.FinalizerDeleteDependents,
+				"example.org/first",
+				metav1.FinalizerOrphanDependents,
+				"example.org/second",
+			}}}},
+			want: []string{"example.org/first", "example.org/second"},
+		},
+	}
+
+	for name, tc := range cases {
+		t.Run(name, func(t *testing.T) {
+			if diff := cmp.Diff(tc.want, NonGCFinalizers(tc.args.o)); diff != "" {
+				t.Errorf("%s\nNonGCFinalizers(...): -want, +got:\n%s", tc.reason, diff)
+			}
+		})
+	}
+}
+
 func TestAddLabels(t *testing.T) {
 	key, value := "key", "value"
 	existingKey, existingValue := "ekey", "evalue"

pkg/reconciler/managed/providerconfigusage_test.go

@@ -0,0 +1,112 @@
+/*
+Copyright 2026 The Crossplane 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 managed
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"k8s.io/apimachinery/pkg/runtime"
+
+	"github.com/crossplane/crossplane-runtime/v2/pkg/resource"
+	"github.com/crossplane/crossplane-runtime/v2/pkg/resource/fake"
+	"github.com/crossplane/crossplane-runtime/v2/pkg/test"
+)
+
+// anotherProviderConfigUsage is a second namespaced usage kind, so a scheme can
+// register more than one of them.
+type anotherProviderConfigUsage struct {
+	fake.ProviderConfigUsage
+}
+
+func (p *anotherProviderConfigUsage) DeepCopyObject() runtime.Object {
+	return &anotherProviderConfigUsage{}
+}
+
+func TestDefaultProviderConfigUsageCleaner(t *testing.T) {
+	type args struct {
+		mg     resource.Managed
+		scheme *runtime.Scheme
+	}
+
+	cases := map[string]struct {
+		reason string
+		args   args
+		want   string
+	}{
+		"LegacyManaged": {
+			reason: "A cluster scoped managed resource gets a legacy tracker for the cluster scoped usage kind in its scheme.",
+			args: args{
+				mg:     &fake.LegacyManaged{},
+				scheme: fake.SchemeWith(&fake.LegacyManaged{}, &fake.LegacyProviderConfigUsage{}, &fake.ProviderConfigUsage{}),
+			},
+			want: "*resource.LegacyProviderConfigUsageTracker",
+		},
+		"ModernManaged": {
+			reason: "A namespaced managed resource gets a tracker for the namespaced usage kind in its scheme.",
+			args: args{
+				mg:     &fake.ModernManaged{},
+				scheme: fake.SchemeWith(&fake.ModernManaged{}, &fake.LegacyProviderConfigUsage{}, &fake.ProviderConfigUsage{}),
+			},
+			want: "*resource.ProviderConfigUsageTracker",
+		},
+		"NoUsageKind": {
+			reason: "A scheme that registers no usage kind yields a cleaner that does nothing.",
+			args: args{
+				mg:     &fake.ModernManaged{},
+				scheme: fake.SchemeWith(&fake.ModernManaged{}),
+			},
+			want: "resource.ProviderConfigUsageCleanerFns",
+		},
+		"UsageKindOfOtherScope": {
+			reason: "A usage kind of the other scope must not be used.",
+			args: args{
+				mg:     &fake.LegacyManaged{},
+				scheme: fake.SchemeWith(&fake.LegacyManaged{}, &fake.ProviderConfigUsage{}),
+			},
+			want: "resource.ProviderConfigUsageCleanerFns",
+		},
+		"AmbiguousUsageKind": {
+			reason: "A scheme that registers several usage kinds of the managed resource's scope yields a cleaner that does nothing.",
+			args: args{
+				mg:     &fake.ModernManaged{},
+				scheme: fake.SchemeWith(&fake.ModernManaged{}, &fake.ProviderConfigUsage{}, &anotherProviderConfigUsage{}),
+			},
+			want: "resource.ProviderConfigUsageCleanerFns",
+		},
+		"UnscopedManaged": {
+			reason: "A managed resource that is neither cluster scoped nor namespaced yields a cleaner that does nothing.",
+			args: args{
+				mg:     &fake.Managed{},
+				scheme: fake.SchemeWith(&fake.Managed{}, &fake.LegacyProviderConfigUsage{}, &fake.ProviderConfigUsage{}),
+			},
+			want: "resource.ProviderConfigUsageCleanerFns",
+		},
+	}
+
+	for name, tc := range cases {
+		t.Run(name, func(t *testing.T) {
+			m := &fake.Manager{Client: &test.MockClient{}, Scheme: tc.args.scheme}
+
+			got := fmt.Sprintf("%T", defaultProviderConfigUsageCleaner(m, tc.args.mg))
+			if diff := cmp.Diff(tc.want, got); diff != "" {
+				t.Errorf("%s\ndefaultProviderConfigUsageCleaner(...): -want, +got:\n%s", tc.reason, diff)
+			}
+		})
+	}
+}