switch to fork of go-git

vendor/github.com/jesseduffield/go-git/v5/plumbing/reference.go

@@ -0,0 +1,209 @@
+package plumbing
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+)
+
+const (
+	refPrefix       = "refs/"
+	refHeadPrefix   = refPrefix + "heads/"
+	refTagPrefix    = refPrefix + "tags/"
+	refRemotePrefix = refPrefix + "remotes/"
+	refNotePrefix   = refPrefix + "notes/"
+	symrefPrefix    = "ref: "
+)
+
+// RefRevParseRules are a set of rules to parse references into short names.
+// These are the same rules as used by git in shorten_unambiguous_ref.
+// See: https://github.com/git/git/blob/e0aaa1b6532cfce93d87af9bc813fb2e7a7ce9d7/refs.c#L417
+var RefRevParseRules = []string{
+	"refs/%s",
+	"refs/tags/%s",
+	"refs/heads/%s",
+	"refs/remotes/%s",
+	"refs/remotes/%s/HEAD",
+}
+
+var (
+	ErrReferenceNotFound = errors.New("reference not found")
+)
+
+// ReferenceType reference type's
+type ReferenceType int8
+
+const (
+	InvalidReference  ReferenceType = 0
+	HashReference     ReferenceType = 1
+	SymbolicReference ReferenceType = 2
+)
+
+func (r ReferenceType) String() string {
+	switch r {
+	case InvalidReference:
+		return "invalid-reference"
+	case HashReference:
+		return "hash-reference"
+	case SymbolicReference:
+		return "symbolic-reference"
+	}
+
+	return ""
+}
+
+// ReferenceName reference name's
+type ReferenceName string
+
+// NewBranchReferenceName returns a reference name describing a branch based on
+// his short name.
+func NewBranchReferenceName(name string) ReferenceName {
+	return ReferenceName(refHeadPrefix + name)
+}
+
+// NewNoteReferenceName returns a reference name describing a note based on his
+// short name.
+func NewNoteReferenceName(name string) ReferenceName {
+	return ReferenceName(refNotePrefix + name)
+}
+
+// NewRemoteReferenceName returns a reference name describing a remote branch
+// based on his short name and the remote name.
+func NewRemoteReferenceName(remote, name string) ReferenceName {
+	return ReferenceName(refRemotePrefix + fmt.Sprintf("%s/%s", remote, name))
+}
+
+// NewRemoteHEADReferenceName returns a reference name describing a the HEAD
+// branch of a remote.
+func NewRemoteHEADReferenceName(remote string) ReferenceName {
+	return ReferenceName(refRemotePrefix + fmt.Sprintf("%s/%s", remote, HEAD))
+}
+
+// NewTagReferenceName returns a reference name describing a tag based on short
+// his name.
+func NewTagReferenceName(name string) ReferenceName {
+	return ReferenceName(refTagPrefix + name)
+}
+
+// IsBranch check if a reference is a branch
+func (r ReferenceName) IsBranch() bool {
+	return strings.HasPrefix(string(r), refHeadPrefix)
+}
+
+// IsNote check if a reference is a note
+func (r ReferenceName) IsNote() bool {
+	return strings.HasPrefix(string(r), refNotePrefix)
+}
+
+// IsRemote check if a reference is a remote
+func (r ReferenceName) IsRemote() bool {
+	return strings.HasPrefix(string(r), refRemotePrefix)
+}
+
+// IsTag check if a reference is a tag
+func (r ReferenceName) IsTag() bool {
+	return strings.HasPrefix(string(r), refTagPrefix)
+}
+
+func (r ReferenceName) String() string {
+	return string(r)
+}
+
+// Short returns the short name of a ReferenceName
+func (r ReferenceName) Short() string {
+	s := string(r)
+	res := s
+	for _, format := range RefRevParseRules {
+		_, err := fmt.Sscanf(s, format, &res)
+		if err == nil {
+			continue
+		}
+	}
+
+	return res
+}
+
+const (
+	HEAD   ReferenceName = "HEAD"
+	Master ReferenceName = "refs/heads/master"
+)
+
+// Reference is a representation of git reference
+type Reference struct {
+	t      ReferenceType
+	n      ReferenceName
+	h      Hash
+	target ReferenceName
+}
+
+// NewReferenceFromStrings creates a reference from name and target as string,
+// the resulting reference can be a SymbolicReference or a HashReference base
+// on the target provided
+func NewReferenceFromStrings(name, target string) *Reference {
+	n := ReferenceName(name)
+
+	if strings.HasPrefix(target, symrefPrefix) {
+		target := ReferenceName(target[len(symrefPrefix):])
+		return NewSymbolicReference(n, target)
+	}
+
+	return NewHashReference(n, NewHash(target))
+}
+
+// NewSymbolicReference creates a new SymbolicReference reference
+func NewSymbolicReference(n, target ReferenceName) *Reference {
+	return &Reference{
+		t:      SymbolicReference,
+		n:      n,
+		target: target,
+	}
+}
+
+// NewHashReference creates a new HashReference reference
+func NewHashReference(n ReferenceName, h Hash) *Reference {
+	return &Reference{
+		t: HashReference,
+		n: n,
+		h: h,
+	}
+}
+
+// Type return the type of a reference
+func (r *Reference) Type() ReferenceType {
+	return r.t
+}
+
+// Name return the name of a reference
+func (r *Reference) Name() ReferenceName {
+	return r.n
+}
+
+// Hash return the hash of a hash reference
+func (r *Reference) Hash() Hash {
+	return r.h
+}
+
+// Target return the target of a symbolic reference
+func (r *Reference) Target() ReferenceName {
+	return r.target
+}
+
+// Strings dump a reference as a [2]string
+func (r *Reference) Strings() [2]string {
+	var o [2]string
+	o[0] = r.Name().String()
+
+	switch r.Type() {
+	case HashReference:
+		o[1] = r.Hash().String()
+	case SymbolicReference:
+		o[1] = symrefPrefix + r.Target().String()
+	}
+
+	return o
+}
+
+func (r *Reference) String() string {
+	s := r.Strings()
+	return fmt.Sprintf("%s %s", s[1], s[0])
+}