Rename Format to Builder.

format.go

-package cid
-
-import (
-	mh "github.com/multiformats/go-multihash"
-)
-
-type Format interface {
-	Sum(data []byte) (*Cid, error)
-	GetCodec() uint64
-	WithCodec(uint64) Format
-}
-
-type FormatV0 struct{}
-
-type FormatV1 struct {
-	Codec   uint64
-	HashFun uint64
-	HashLen int // HashLen <= 0 means the default length
-}
-
-func PrefixToFormat(p Prefix) Format {
-	if p.Version == 0 {
-		return FormatV0{}
-	}
-	mhLen := p.MhLength
-	if p.MhType == mh.ID {
-		mhLen = 0
-	}
-	if mhLen < 0 {
-		mhLen = 0
-	}
-	return FormatV1{
-		Codec:   p.Codec,
-		HashFun: p.MhType,
-		HashLen: mhLen,
-	}
-}
-
-func (p Prefix) GetCodec() uint64 {
-	return p.Codec
-}
-
-func (p Prefix) WithCodec(c uint64) Format {
-	if c == p.Codec {
-		return p
-	}
-	p.Codec = c
-	if c != DagProtobuf {
-		p.Version = 1
-	}
-	return p
-}
-
-func (p FormatV0) Sum(data []byte) (*Cid, error) {
-	hash, err := mh.Sum(data, mh.SHA2_256, -1)
-	if err != nil {
-		return nil, err
-	}
-	return NewCidV0(hash), nil
-}
-
-func (p FormatV0) GetCodec() uint64 {
-	return DagProtobuf
-}
-
-func (p FormatV0) WithCodec(c uint64) Format {
-	if c == DagProtobuf {
-		return p
-	}
-	return FormatV1{Codec: c, HashFun: mh.SHA2_256}
-}
-
-func (p FormatV1) Sum(data []byte) (*Cid, error) {
-	mhLen := p.HashLen
-	if mhLen <= 0 {
-		mhLen = -1
-	}
-	hash, err := mh.Sum(data, p.HashFun, mhLen)
-	if err != nil {
-		return nil, err
-	}
-	return NewCidV1(p.Codec, hash), nil
-}
-
-func (p FormatV1) GetCodec() uint64 {
-	return p.Codec
-}
-
-func (p FormatV1) WithCodec(c uint64) Format {
-	p.Codec = c
-	return p
-}

format_test.go

-package cid
-
-import (
-	"testing"
-
-	mh "github.com/multiformats/go-multihash"
-)
-
-func TestFormatV1(t *testing.T) {
-	data := []byte("this is some test content")
-
-	// Construct c1
-	format := FormatV1{Codec: DagCBOR, HashFun: mh.SHA2_256}
-	c1, err := format.Sum(data)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Construct c2
-	hash, err := mh.Sum(data, mh.SHA2_256, -1)
-	if err != nil {
-		t.Fatal(err)
-	}
-	c2 := NewCidV1(DagCBOR, hash)
-
-	if !c1.Equals(c2) {
-		t.Fatal("cids mismatch")
-	}
-	if c1.Prefix() != c2.Prefix() {
-		t.Fatal("prefixes mismatch")
-	}
-}
-
-func TestFormatV0(t *testing.T) {
-	data := []byte("this is some test content")
-
-	// Construct c1
-	format := FormatV0{}
-	c1, err := format.Sum(data)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Construct c2
-	hash, err := mh.Sum(data, mh.SHA2_256, -1)
-	if err != nil {
-		t.Fatal(err)
-	}
-	c2 := NewCidV0(hash)
-
-	if !c1.Equals(c2) {
-		t.Fatal("cids mismatch")
-	}
-	if c1.Prefix() != c2.Prefix() {
-		t.Fatal("prefixes mismatch")
-	}
-}
-