package testutil import "context" type FakeFileDownloader struct { Data []byte MimeType string Error error } func (f *FakeFileDownloader) Download(_ context.Context, _ string) ([]byte, string, error) { return f.Data, f.MimeType, f.Error } type FakeAudioConverter struct { Output []byte Error error } func (f *FakeAudioConverter) Convert(_ context.Context, _ []byte, _, _ string) ([]byte, error) { if f.Output != nil { return f.Output, f.Error } return []byte("converted-audio"), f.Error }