aboutsummaryrefslogtreecommitdiffstats
path: root/config/refspec.go
blob: 391705ccccef967ceb2bc7716444e545cf14b2e5 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
package config

import (
	"errors"
	"strings"

	"gopkg.in/src-d/go-git.v4/plumbing"
)

const (
	refSpecWildcard  = "*"
	refSpecForce     = "+"
	refSpecSeparator = ":"
)

var (
	ErrRefSpecMalformedSeparator = errors.New("malformed refspec, separators are wrong")
	ErrRefSpecMalformedWildcard  = errors.New("malformed refspec, mismatched number of wildcards")
)

// RefSpec is a mapping from local branches to remote references
// The format of the refspec is an optional +, followed by <src>:<dst>, where
// <src> is the pattern for references on the remote side and <dst> is where
// those references will be written locally. The + tells Git to update the
// reference even if it isn’t a fast-forward.
// eg.: "+refs/heads/*:refs/remotes/origin/*"
//
// https://git-scm.com/book/es/v2/Git-Internals-The-Refspec
type RefSpec string

// Validate validates the RefSpec
func (s RefSpec) Validate() error {
	spec := string(s)
	if strings.Count(spec, refSpecSeparator) != 1 {
		return ErrRefSpecMalformedSeparator
	}

	sep := strings.Index(spec, refSpecSeparator)
	if sep == len(spec)-1 {
		return ErrRefSpecMalformedSeparator
	}

	ws := strings.Count(spec[0:sep], refSpecWildcard)
	wd := strings.Count(spec[sep+1:], refSpecWildcard)
	if ws == wd && ws < 2 && wd < 2 {
		return nil
	}

	return ErrRefSpecMalformedWildcard
}

// IsForceUpdate returns if update is allowed in non fast-forward merges.
func (s RefSpec) IsForceUpdate() bool {
	return s[0] == refSpecForce[0]
}

// IsDelete returns true if the refspec indicates a delete (empty src).
func (s RefSpec) IsDelete() bool {
	return s[0] == refSpecSeparator[0]
}

// Src return the src side.
func (s RefSpec) Src() string {
	spec := string(s)

	var start int
	if s.IsForceUpdate() {
		start = 1
	} else {
		start = 0
	}
	end := strings.Index(spec, refSpecSeparator)

	return spec[start:end]
}

// Match match the given plumbing.ReferenceName against the source.
func (s RefSpec) Match(n plumbing.ReferenceName) bool {
	if !s.IsWildcard() {
		return s.matchExact(n)
	}

	return s.matchGlob(n)
}

// IsWildcard returns true if the RefSpec contains a wildcard.
func (s RefSpec) IsWildcard() bool {
	return strings.Contains(string(s), refSpecWildcard)
}

func (s RefSpec) matchExact(n plumbing.ReferenceName) bool {
	return s.Src() == n.String()
}

func (s RefSpec) matchGlob(n plumbing.ReferenceName) bool {
	src := s.Src()
	name := n.String()
	wildcard := strings.Index(src, refSpecWildcard)

	var prefix, suffix string
	prefix = src[0:wildcard]
	if len(src) < wildcard {
		suffix = src[wildcard+1 : len(suffix)]
	}

	return len(name) > len(prefix)+len(suffix) &&
		strings.HasPrefix(name, prefix) &&
		strings.HasSuffix(name, suffix)
}

// Dst returns the destination for the given remote reference.
func (s RefSpec) Dst(n plumbing.ReferenceName) plumbing.ReferenceName {
	spec := string(s)
	start := strings.Index(spec, refSpecSeparator) + 1
	dst := spec[start:]
	src := s.Src()

	if !s.IsWildcard() {
		return plumbing.ReferenceName(dst)
	}

	name := n.String()
	ws := strings.Index(src, refSpecWildcard)
	wd := strings.Index(dst, refSpecWildcard)
	match := name[ws : len(name)-(len(src)-(ws+1))]

	return plumbing.ReferenceName(dst[0:wd] + match + dst[wd+1:])
}

func (s RefSpec) String() string {
	return string(s)
}

// MatchAny returns true if any of the RefSpec match with the given ReferenceName.
func MatchAny(l []RefSpec, n plumbing.ReferenceName) bool {
	for _, r := range l {
		if r.Match(n) {
			return true
		}
	}

	return false
}