code: func (c *MockStore) Search(ctx context.Context, metric schema.AMKey, ttl, start, end uint32) ([]chunk.IterGen, error) {
  	var itgens, res []chunk.IterGen
  	var ok bool
  
  	if itgens, ok = c.results[metric]; !ok {
  		return res, errors.New("metric not found")
  	}
  
  	for _, itgen := range itgens {
  		// start is inclusive, end is exclusive
  		if itgen.T0 < end && itgen.EndTs() > start && start < end {
  			res = append(res, itgen)
  		}
  	}
  
  	return res, nil
  }
docs: // searches through the mock results and returns the right ones according to start / end