Added tests for cmd/descheduler

Signed-off-by: Anuj Agrawal <anujagrawal380@gmail.com>

Added tests for cmd/descheduler

Signed-off-by: Anuj Agrawal <anujagrawal380@gmail.com>

cmd/descheduler/app/descheduler_test.go

@@ -0,0 +1,128 @@
+/*
+Copyright 2024 The Karmada 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 app
+
+import (
+	"net/http"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/karmada-io/karmada/cmd/descheduler/app/options"
+)
+
+func TestNewDeschedulerCommand(t *testing.T) {
+	stopCh := make(chan struct{})
+	cmd := NewDeschedulerCommand(stopCh)
+
+	assert.NotNil(t, cmd)
+	assert.Equal(t, "karmada-descheduler", cmd.Use)
+	assert.NotEmpty(t, cmd.Long)
+}
+
+func TestDeschedulerCommandFlagParsing(t *testing.T) {
+	testCases := []struct {
+		name        string
+		args        []string
+		expectError bool
+	}{
+		{"Default flags", []string{}, false},
+		{"With custom health probe bind address", []string{"--health-probe-bind-address=127.0.0.1:8080"}, false},
+		{"With custom metrics bind address", []string{"--metrics-bind-address=127.0.0.1:8081"}, false},
+		{"With leader election enabled", []string{"--leader-elect=true"}, false},
+		{"With invalid flag", []string{"--invalid-flag=value"}, true},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			stopCh := make(chan struct{})
+			cmd := NewDeschedulerCommand(stopCh)
+			cmd.SetArgs(tc.args)
+			err := cmd.ParseFlags(tc.args)
+			if tc.expectError {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+			}
+		})
+	}
+}
+
+func TestServeHealthzAndMetrics(t *testing.T) {
+	healthAddress := "127.0.0.1:8082"
+	metricsAddress := "127.0.0.1:8083"
+
+	go serveHealthzAndMetrics(healthAddress, metricsAddress)
+
+	// For servers to start
+	time.Sleep(100 * time.Millisecond)
+
+	t.Run("Healthz endpoint", func(t *testing.T) {
+		resp, err := http.Get("http://" + healthAddress + "/healthz")
+		require.NoError(t, err)
+		assert.Equal(t, http.StatusOK, resp.StatusCode)
+	})
+
+	t.Run("Metrics endpoint", func(t *testing.T) {
+		resp, err := http.Get("http://" + metricsAddress + "/metrics")
+		require.NoError(t, err)
+		assert.Equal(t, http.StatusOK, resp.StatusCode)
+	})
+}
+
+func TestDeschedulerOptionsValidation(t *testing.T) {
+	testCases := []struct {
+		name        string
+		setupOpts   func(*options.Options)
+		expectError bool
+	}{
+		{
+			name: "Default options",
+			setupOpts: func(_ *options.Options) {
+				// Default options are valid
+			},
+			expectError: false,
+		},
+		{
+			name: "Invalid descheduling interval",
+			setupOpts: func(o *options.Options) {
+				o.DeschedulingInterval.Duration = -1 * time.Second
+			},
+			expectError: true,
+		},
+		{
+			name: "Invalid unschedulable threshold",
+			setupOpts: func(o *options.Options) {
+				o.UnschedulableThreshold.Duration = -1 * time.Second
+			},
+			expectError: true,
+		},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			opts := options.NewOptions()
+			tc.setupOpts(opts)
+			errs := opts.Validate()
+			if tc.expectError {
+				assert.NotEmpty(t, errs)
+			} else {
+				assert.Empty(t, errs)
+			}
+		})
+	}
+}