test: added tests for the ReplicaSet analyzer (#997)

This commit introduces comprehensive tests for the ReplicaSet analyzer
defined in the `pkg/analyzer` package.

Adding these tests increases the code coverage of the `rs.go` file to
>95%.

Partially addresses: #889

Signed-off-by: VaibhavMalik4187 <vaibhavmalik2018@gmail.com>

pkg/analyzer/rs_test.go

@@ -0,0 +1,151 @@
+/*
+Copyright 2024 The K8sGPT 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 analyzer
+
+import (
+	"context"
+	"sort"
+	"testing"
+
+	"github.com/k8sgpt-ai/k8sgpt/pkg/common"
+	"github.com/k8sgpt-ai/k8sgpt/pkg/kubernetes"
+	"github.com/stretchr/testify/require"
+	appsv1 "k8s.io/api/apps/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes/fake"
+)
+
+func TestReplicaSetAnalyzer(t *testing.T) {
+	config := common.Analyzer{
+		Client: &kubernetes.Client{
+			Client: fake.NewSimpleClientset(
+				&appsv1.ReplicaSet{
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "ReplicaSet1",
+						Namespace: "default",
+					},
+					Status: appsv1.ReplicaSetStatus{
+						Replicas: 0,
+						Conditions: []appsv1.ReplicaSetCondition{
+							{
+								// Should contribute to failures.
+								Type:    appsv1.ReplicaSetReplicaFailure,
+								Reason:  "FailedCreate",
+								Message: "failed to create test replica set 1",
+							},
+						},
+					},
+				},
+				&appsv1.ReplicaSet{
+					// This replicaset won't be discovered as it is not in the
+					// default namespace.
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "ReplicaSet2",
+						Namespace: "test",
+					},
+				},
+				&appsv1.ReplicaSet{
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "ReplicaSet3",
+						Namespace: "default",
+					},
+					Status: appsv1.ReplicaSetStatus{
+						Replicas: 0,
+						Conditions: []appsv1.ReplicaSetCondition{
+							{
+								Type: appsv1.ReplicaSetReplicaFailure,
+								// Should not be included in the failures.
+								Reason: "RandomError",
+							},
+						},
+					},
+				},
+				&appsv1.ReplicaSet{
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "ReplicaSet4",
+						Namespace: "default",
+					},
+					Status: appsv1.ReplicaSetStatus{
+						Replicas: 0,
+						Conditions: []appsv1.ReplicaSetCondition{
+							{
+								// Should contribute to failures.
+								Type:    appsv1.ReplicaSetReplicaFailure,
+								Reason:  "FailedCreate",
+								Message: "failed to create test replica set 4 condition 1",
+							},
+							{
+								// Should not contribute to failures.
+								Type:   appsv1.ReplicaSetReplicaFailure,
+								Reason: "Unknown",
+							},
+							{
+								// Should not contribute to failures.
+								Type:    appsv1.ReplicaSetReplicaFailure,
+								Reason:  "FailedCreate",
+								Message: "failed to create test replica set 4 condition 3",
+							},
+						},
+					},
+				},
+				&appsv1.ReplicaSet{
+					// Replicaset without any failures.
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "ReplicaSet5",
+						Namespace: "default",
+					},
+					Status: appsv1.ReplicaSetStatus{
+						Replicas: 3,
+					},
+				},
+			),
+		},
+		Context:   context.Background(),
+		Namespace: "default",
+	}
+
+	rsAnalyzer := ReplicaSetAnalyzer{}
+	results, err := rsAnalyzer.Analyze(config)
+	require.NoError(t, err)
+
+	sort.Slice(results, func(i, j int) bool {
+		return results[i].Name < results[j].Name
+	})
+
+	expectations := []struct {
+		name         string
+		failuresText []string
+	}{
+		{
+			name: "default/ReplicaSet1",
+			failuresText: []string{
+				"failed to create test replica set 1",
+			},
+		},
+		{
+			name: "default/ReplicaSet4",
+			failuresText: []string{
+				"failed to create test replica set 4 condition 1",
+				"failed to create test replica set 4 condition 3",
+			},
+		},
+	}
+
+	for i, result := range results {
+		require.Equal(t, expectations[i].name, result.Name)
+		for j, failure := range result.Error {
+			require.Equal(t, expectations[i].failuresText[j], failure.Text)
+		}
+	}
+}