if err != nil && pmain.Error == nil {
			pmain.Error = &PackageError{Err: err}
			pmain.Incomplete = true
		}
		// Set TestmainGo even if it is empty: the presence of a TestmainGo
		// indicates that this package is, in fact, a test main.
		pmain.Internal.TestmainGo = &data
	}

	if done != nil {
		go func() {
			parallelizablePart()
			done()
		}()
	} else {
		parallelizablePart()
	}