return nil, errMain
}
func (f matchStringOnly) CheckCorpus([]any, []reflect.Type) error { return nil }
func (f matchStringOnly) ResetCoverage()                          {}
func (f matchStringOnly) SnapshotCoverage()                       {}

func (f matchStringOnly) InitRuntimeCoverage() (mode string, tearDown func(string, string) (string, error), snapcov func() float64) {
	return
}