Improve backup log command UT coverage.

Signed-off-by: Xun Jiang <[email protected]>

pkg/cmd/cli/backup/logs_test.go

@@ -143,4 +143,24 @@ func TestNewLogsCommand(t *testing.T) {
 		case <-done:
 		}
 	})
+
+	t.Run("Invalid client test", func(t *testing.T) {
+		// create a factory
+		f := &factorymocks.Factory{}
+
+		kbClient := velerotest.NewFakeControllerRuntimeClient(t)
+
+		f.On("Namespace").Return(cmdtest.VeleroNameSpace)
+
+		c := NewLogsCommand(f)
+		assert.Equal(t, "Get backup logs", c.Short)
+
+		l := NewLogsOptions()
+		flags := new(flag.FlagSet)
+		l.BindFlags(flags)
+
+		f.On("KubebuilderClient").Return(kbClient, fmt.Errorf("test error"))
+		err := l.Complete([]string{""}, f)
+		require.Equal(t, "test error", err.Error())
+	})
 }