func waitForDetach( t *testing.T, fakePlugin *volumetesting.FakeVolumePlugin, volumeName api.UniqueVolumeName, asw cache.ActualStateOfWorld) { err := retryWithExponentialBackOff( time.Duration(5*time.Millisecond), func() (bool, error) { if asw.VolumeExists(volumeName) { return false, nil } return true, nil }, ) if err != nil { t.Fatalf("Timed out waiting for volume %q to be detached.", volumeName) } }