test(fluidapp): add Ginkgo controller unit coverage (#5828)

* test(fluidapp): add ginkgo controller unit coverage

Signed-off-by: Harsh <harshmastic@gmail.com>

* test(fluidapp): tighten reconciler coverage gaps

Signed-off-by: Harsh <harshmastic@gmail.com>

---------

Signed-off-by: Harsh <harshmastic@gmail.com>

Author: hxrshxz

pkg/controllers/v1alpha1/fluidapp/fluidapp_controller_ut_test.go

@@ -0,0 +1,237 @@
+/*
+Copyright 2026 The Fluid 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 fluidapp
+
+import (
+	"context"
+	"errors"
+
+	"github.com/agiledragon/gomonkey/v2"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/client-go/tools/record"
+	ctrl "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/reconcile"
+
+	datav1alpha1 "github.com/fluid-cloudnative/fluid/api/v1alpha1"
+	"github.com/fluid-cloudnative/fluid/pkg/common"
+	"github.com/fluid-cloudnative/fluid/pkg/utils/fake"
+	"github.com/fluid-cloudnative/fluid/pkg/utils/kubeclient"
+)
+
+var _ = Describe("FluidAppReconciler", func() {
+	const (
+		testNamespace = "default"
+		testPodName   = "fluidapp-pod"
+	)
+
+	var scheme *runtime.Scheme
+	var patches *gomonkey.Patches
+
+	BeforeEach(func() {
+		scheme = runtime.NewScheme()
+		Expect(corev1.AddToScheme(scheme)).To(Succeed())
+		Expect(datav1alpha1.AddToScheme(scheme)).To(Succeed())
+	})
+
+	AfterEach(func() {
+		if patches != nil {
+			patches.Reset()
+			patches = nil
+		}
+	})
+
+	Describe("ControllerName", func() {
+		It("returns the controller name constant", func() {
+			r := &FluidAppReconciler{}
+			Expect(r.ControllerName()).To(Equal(controllerName))
+		})
+	})
+
+	Describe("ManagedResource", func() {
+		It("returns a pod object", func() {
+			r := &FluidAppReconciler{}
+			Expect(r.ManagedResource()).To(BeAssignableToTypeOf(&corev1.Pod{}))
+		})
+	})
+
+	Describe("NewFluidAppReconciler", func() {
+		It("constructs a reconciler with the provided dependencies", func() {
+			fakeClient := fake.NewFakeClientWithScheme(scheme)
+			recorder := record.NewFakeRecorder(10)
+
+			r := NewFluidAppReconciler(fakeClient, fake.NullLogger(), recorder)
+
+			Expect(r).NotTo(BeNil())
+			Expect(r.Client).To(Equal(fakeClient))
+			Expect(r.Recorder).To(Equal(recorder))
+			Expect(r.FluidAppReconcilerImplement).NotTo(BeNil())
+			Expect(r.FluidAppReconcilerImplement.Client).To(Equal(fakeClient))
+		})
+	})
+
+	Describe("Reconcile", func() {
+		It("returns the pod lookup error", func() {
+			expectedErr := errors.New("get pod failed")
+			patches = gomonkey.ApplyFunc(kubeclient.GetPodByName, func(_ client.Client, name, namespace string) (*corev1.Pod, error) {
+				Expect(name).To(Equal(testPodName))
+				Expect(namespace).To(Equal(testNamespace))
+				return nil, expectedErr
+			})
+
+			r := NewFluidAppReconciler(fake.NewFakeClientWithScheme(scheme), fake.NullLogger(), record.NewFakeRecorder(10))
+
+			result, err := r.Reconcile(context.Background(), reconcile.Request{
+				NamespacedName: types.NamespacedName{Name: testPodName, Namespace: testNamespace},
+			})
+
+			Expect(err).To(MatchError(expectedErr))
+			Expect(result).To(Equal(ctrl.Result{}))
+		})
+
+		It("returns no requeue when the pod does not exist", func() {
+			fakeClient := fake.NewFakeClientWithScheme(scheme)
+			r := NewFluidAppReconciler(fakeClient, fake.NullLogger(), record.NewFakeRecorder(10))
+
+			result, err := r.Reconcile(context.Background(), reconcile.Request{
+				NamespacedName: types.NamespacedName{Name: testPodName, Namespace: testNamespace},
+			})
+
+			Expect(err).NotTo(HaveOccurred())
+			Expect(result).To(Equal(ctrl.Result{}))
+		})
+
+		It("returns no requeue when the pod should not enter the queue", func() {
+			pod := &corev1.Pod{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      testPodName,
+					Namespace: testNamespace,
+				},
+			}
+			fakeClient := fake.NewFakeClientWithScheme(scheme, pod)
+			r := NewFluidAppReconciler(fakeClient, fake.NullLogger(), record.NewFakeRecorder(10))
+
+			result, err := r.Reconcile(context.Background(), reconcile.Request{
+				NamespacedName: types.NamespacedName{Name: testPodName, Namespace: testNamespace},
+			})
+
+			Expect(err).NotTo(HaveOccurred())
+			Expect(result).To(Equal(ctrl.Result{}))
+		})
+
+		It("reconciles queueable pods and returns no requeue on successful fuse unmount", func() {
+			pod := &corev1.Pod{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      testPodName,
+					Namespace: testNamespace,
+					Labels: map[string]string{
+						common.InjectServerless:  common.True,
+						common.InjectSidecarDone: common.True,
+					},
+				},
+				Spec: corev1.PodSpec{
+					RestartPolicy: corev1.RestartPolicyNever,
+					Containers: []corev1.Container{
+						{Name: "app"},
+						{
+							Name: common.FuseContainerName + "-0",
+							Lifecycle: &corev1.Lifecycle{
+								PreStop: &corev1.LifecycleHandler{
+									Exec: &corev1.ExecAction{Command: []string{"umount", "/mnt/fuse"}},
+								},
+							},
+						},
+					},
+				},
+				Status: corev1.PodStatus{
+					Phase: corev1.PodRunning,
+					ContainerStatuses: []corev1.ContainerStatus{
+						{
+							Name:  "app",
+							State: corev1.ContainerState{Terminated: &corev1.ContainerStateTerminated{ExitCode: 0}},
+						},
+						{
+							Name:  common.FuseContainerName + "-0",
+							State: corev1.ContainerState{Running: &corev1.ContainerStateRunning{}},
+						},
+					},
+				},
+			}
+
+			fakeClient := fake.NewFakeClientWithScheme(scheme, pod)
+			r := NewFluidAppReconciler(fakeClient, fake.NullLogger(), record.NewFakeRecorder(10))
+
+			patches = gomonkey.ApplyFunc((*FluidAppReconcilerImplement).umountFuseSidecars, func(_ *FluidAppReconcilerImplement, gotPod *corev1.Pod) error {
+				Expect(gotPod.Name).To(Equal(testPodName))
+				return nil
+			})
+
+			result, err := r.Reconcile(context.Background(), reconcile.Request{
+				NamespacedName: types.NamespacedName{Name: testPodName, Namespace: testNamespace},
+			})
+
+			Expect(err).NotTo(HaveOccurred())
+			Expect(result).To(Equal(ctrl.Result{}))
+		})
+	})
+
+	Describe("internalReconcile", func() {
+		It("requeues when unmounting fuse sidecars returns an error", func() {
+			r := NewFluidAppReconciler(fake.NewFakeClientWithScheme(scheme), fake.NullLogger(), record.NewFakeRecorder(10))
+			pod := &corev1.Pod{ObjectMeta: metav1.ObjectMeta{Name: testPodName, Namespace: testNamespace}}
+			expectedErr := errors.New("umount failed")
+
+			patches = gomonkey.ApplyFunc((*FluidAppReconcilerImplement).umountFuseSidecars, func(_ *FluidAppReconcilerImplement, gotPod *corev1.Pod) error {
+				Expect(gotPod).To(Equal(pod))
+				return expectedErr
+			})
+
+			result, err := r.internalReconcile(reconcileRequestContext{
+				Context: context.Background(),
+				Log:     fake.NullLogger(),
+				pod:     pod,
+			})
+
+			Expect(err).To(MatchError(expectedErr))
+			Expect(result).To(Equal(ctrl.Result{}))
+		})
+
+		It("returns no requeue when unmounting fuse sidecars succeeds", func() {
+			r := NewFluidAppReconciler(fake.NewFakeClientWithScheme(scheme), fake.NullLogger(), record.NewFakeRecorder(10))
+			pod := &corev1.Pod{ObjectMeta: metav1.ObjectMeta{Name: testPodName, Namespace: testNamespace}}
+
+			patches = gomonkey.ApplyFunc((*FluidAppReconcilerImplement).umountFuseSidecars, func(_ *FluidAppReconcilerImplement, gotPod *corev1.Pod) error {
+				Expect(gotPod).To(Equal(pod))
+				return nil
+			})
+
+			result, err := r.internalReconcile(reconcileRequestContext{
+				Context: context.Background(),
+				Log:     fake.NullLogger(),
+				pod:     pod,
+			})
+
+			Expect(err).NotTo(HaveOccurred())
+			Expect(result).To(Equal(ctrl.Result{}))
+		})
+	})
+})