func (s *scratch) bytes() []byte { return s.data[0:s.fill] }

// grow scratch buffer
func (s *scratch) grow() {
	ndata := make([]byte, cap(s.data)*2)
	copy(ndata, s.data)
	s.data = ndata
}

// append single byte to scratch buffer
func (s *scratch) add(c byte) {
	if s.fill+1 >= cap(s.data) {
		s.grow()
	}

	s.data[s.fill] = c
	s.fill++
}

// append encoded rune to scratch buffer

// for multipart checksum
func TestChecksumSerializeDeserializeMultiPart(t *testing.T) {
	// Create dummy data that we'll split into 3 parts
	dummyData := []byte("The quick brown fox jumps over the lazy dog. " +
		"Pack my box with five dozen brown eggs. " +
		"Have another go it will all make sense in the end!")

	// Split data into 3 parts
	partSize := len(dummyData) / 3
	part1Data := dummyData[0:partSize]

			return
		}

		if db.Statement.Schema != nil {
			for _, c := range db.Statement.Schema.UpdateClauses {
				db.Statement.AddClause(c)
			}
		}

		if db.Statement.SQL.Len() == 0 {
			db.Statement.SQL.Grow(180)
			db.Statement.AddClauseIfNotExists(clause.Update{})
			if _, ok := db.Statement.Clauses["SET"]; !ok {
				if set := ConvertToAssignments(db.Statement); len(set) != 0 {
					defer delete(db.Statement.Clauses, "SET")

		}

		if db.Statement.Schema != nil {
			for _, c := range db.Statement.Schema.DeleteClauses {
				db.Statement.AddClause(c)
			}
		}

		if db.Statement.SQL.Len() == 0 {
			db.Statement.SQL.Grow(100)
			db.Statement.AddClauseIfNotExists(clause.Delete{})

			if db.Statement.Schema != nil {