add test that uses NewCancelRunnable

Signed-off-by: Tim Ramlot <42113979+inteon@users.noreply.github.com>

pkg/internal/controller/controller_test.go

@@ -42,6 +42,7 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/handler"
 	ctrlmetrics "sigs.k8s.io/controller-runtime/pkg/internal/controller/metrics"
 	"sigs.k8s.io/controller-runtime/pkg/internal/log"
+	"sigs.k8s.io/controller-runtime/pkg/manager"
 	"sigs.k8s.io/controller-runtime/pkg/predicate"
 	"sigs.k8s.io/controller-runtime/pkg/reconcile"
 	"sigs.k8s.io/controller-runtime/pkg/source"
@@ -345,6 +346,30 @@ var _ = Describe("controller", func() {
 			Expect(err.Error()).To(Equal("can not restart a stopped controller, you should create a new one"))
 		})
 
+		It("should be possible to cancel the controller using NewCancelRunnable", func() {
+			stoppedChan := make(chan struct{})
+			cancellableController, cancel := manager.NewCancelRunnable(ctrl)
+
+			go func() {
+				defer close(stoppedChan)
+				defer GinkgoRecover()
+				Expect(cancellableController.Start(context.Background())).NotTo(HaveOccurred())
+			}()
+
+			var started bool
+			for !started {
+				func() {
+					ctrl.mu.Lock()
+					defer ctrl.mu.Unlock()
+					started = ctrl.Started
+				}()
+			}
+
+			cancel()
+
+			<-stoppedChan
+			Eventually(ctrl.Stopped).Should(BeTrue())
+		})
 	})
 
 	Describe("Processing queue items from a Controller", func() {