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-rw-r--r--vendor/github.com/dlclark/regexp2/match.go347
1 files changed, 347 insertions, 0 deletions
diff --git a/vendor/github.com/dlclark/regexp2/match.go b/vendor/github.com/dlclark/regexp2/match.go
new file mode 100644
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+++ b/vendor/github.com/dlclark/regexp2/match.go
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+package regexp2
+
+import (
+ "bytes"
+ "fmt"
+)
+
+// Match is a single regex result match that contains groups and repeated captures
+// -Groups
+// -Capture
+type Match struct {
+ Group //embeded group 0
+
+ regex *Regexp
+ otherGroups []Group
+
+ // input to the match
+ textpos int
+ textstart int
+
+ capcount int
+ caps []int
+ sparseCaps map[int]int
+
+ // output from the match
+ matches [][]int
+ matchcount []int
+
+ // whether we've done any balancing with this match. If we
+ // have done balancing, we'll need to do extra work in Tidy().
+ balancing bool
+}
+
+// Group is an explicit or implit (group 0) matched group within the pattern
+type Group struct {
+ Capture // the last capture of this group is embeded for ease of use
+
+ Name string // group name
+ Captures []Capture // captures of this group
+}
+
+// Capture is a single capture of text within the larger original string
+type Capture struct {
+ // the original string
+ text []rune
+ // the position in the original string where the first character of
+ // captured substring was found.
+ Index int
+ // the length of the captured substring.
+ Length int
+}
+
+// String returns the captured text as a String
+func (c *Capture) String() string {
+ return string(c.text[c.Index : c.Index+c.Length])
+}
+
+// Runes returns the captured text as a rune slice
+func (c *Capture) Runes() []rune {
+ return c.text[c.Index : c.Index+c.Length]
+}
+
+func newMatch(regex *Regexp, capcount int, text []rune, startpos int) *Match {
+ m := Match{
+ regex: regex,
+ matchcount: make([]int, capcount),
+ matches: make([][]int, capcount),
+ textstart: startpos,
+ balancing: false,
+ }
+ m.Name = "0"
+ m.text = text
+ m.matches[0] = make([]int, 2)
+ return &m
+}
+
+func newMatchSparse(regex *Regexp, caps map[int]int, capcount int, text []rune, startpos int) *Match {
+ m := newMatch(regex, capcount, text, startpos)
+ m.sparseCaps = caps
+ return m
+}
+
+func (m *Match) reset(text []rune, textstart int) {
+ m.text = text
+ m.textstart = textstart
+ for i := 0; i < len(m.matchcount); i++ {
+ m.matchcount[i] = 0
+ }
+ m.balancing = false
+}
+
+func (m *Match) tidy(textpos int) {
+
+ interval := m.matches[0]
+ m.Index = interval[0]
+ m.Length = interval[1]
+ m.textpos = textpos
+ m.capcount = m.matchcount[0]
+ //copy our root capture to the list
+ m.Group.Captures = []Capture{m.Group.Capture}
+
+ if m.balancing {
+ // The idea here is that we want to compact all of our unbalanced captures. To do that we
+ // use j basically as a count of how many unbalanced captures we have at any given time
+ // (really j is an index, but j/2 is the count). First we skip past all of the real captures
+ // until we find a balance captures. Then we check each subsequent entry. If it's a balance
+ // capture (it's negative), we decrement j. If it's a real capture, we increment j and copy
+ // it down to the last free position.
+ for cap := 0; cap < len(m.matchcount); cap++ {
+ limit := m.matchcount[cap] * 2
+ matcharray := m.matches[cap]
+
+ var i, j int
+
+ for i = 0; i < limit; i++ {
+ if matcharray[i] < 0 {
+ break
+ }
+ }
+
+ for j = i; i < limit; i++ {
+ if matcharray[i] < 0 {
+ // skip negative values
+ j--
+ } else {
+ // but if we find something positive (an actual capture), copy it back to the last
+ // unbalanced position.
+ if i != j {
+ matcharray[j] = matcharray[i]
+ }
+ j++
+ }
+ }
+
+ m.matchcount[cap] = j / 2
+ }
+
+ m.balancing = false
+ }
+}
+
+// isMatched tells if a group was matched by capnum
+func (m *Match) isMatched(cap int) bool {
+ return cap < len(m.matchcount) && m.matchcount[cap] > 0 && m.matches[cap][m.matchcount[cap]*2-1] != (-3+1)
+}
+
+// matchIndex returns the index of the last specified matched group by capnum
+func (m *Match) matchIndex(cap int) int {
+ i := m.matches[cap][m.matchcount[cap]*2-2]
+ if i >= 0 {
+ return i
+ }
+
+ return m.matches[cap][-3-i]
+}
+
+// matchLength returns the length of the last specified matched group by capnum
+func (m *Match) matchLength(cap int) int {
+ i := m.matches[cap][m.matchcount[cap]*2-1]
+ if i >= 0 {
+ return i
+ }
+
+ return m.matches[cap][-3-i]
+}
+
+// Nonpublic builder: add a capture to the group specified by "c"
+func (m *Match) addMatch(c, start, l int) {
+
+ if m.matches[c] == nil {
+ m.matches[c] = make([]int, 2)
+ }
+
+ capcount := m.matchcount[c]
+
+ if capcount*2+2 > len(m.matches[c]) {
+ oldmatches := m.matches[c]
+ newmatches := make([]int, capcount*8)
+ copy(newmatches, oldmatches[:capcount*2])
+ m.matches[c] = newmatches
+ }
+
+ m.matches[c][capcount*2] = start
+ m.matches[c][capcount*2+1] = l
+ m.matchcount[c] = capcount + 1
+ //log.Printf("addMatch: c=%v, i=%v, l=%v ... matches: %v", c, start, l, m.matches)
+}
+
+// Nonpublic builder: Add a capture to balance the specified group. This is used by the
+// balanced match construct. (?<foo-foo2>...)
+//
+// If there were no such thing as backtracking, this would be as simple as calling RemoveMatch(c).
+// However, since we have backtracking, we need to keep track of everything.
+func (m *Match) balanceMatch(c int) {
+ m.balancing = true
+
+ // we'll look at the last capture first
+ capcount := m.matchcount[c]
+ target := capcount*2 - 2
+
+ // first see if it is negative, and therefore is a reference to the next available
+ // capture group for balancing. If it is, we'll reset target to point to that capture.
+ if m.matches[c][target] < 0 {
+ target = -3 - m.matches[c][target]
+ }
+
+ // move back to the previous capture
+ target -= 2
+
+ // if the previous capture is a reference, just copy that reference to the end. Otherwise, point to it.
+ if target >= 0 && m.matches[c][target] < 0 {
+ m.addMatch(c, m.matches[c][target], m.matches[c][target+1])
+ } else {
+ m.addMatch(c, -3-target, -4-target /* == -3 - (target + 1) */)
+ }
+}
+
+// Nonpublic builder: removes a group match by capnum
+func (m *Match) removeMatch(c int) {
+ m.matchcount[c]--
+}
+
+// GroupCount returns the number of groups this match has matched
+func (m *Match) GroupCount() int {
+ return len(m.matchcount)
+}
+
+// GroupByName returns a group based on the name of the group, or nil if the group name does not exist
+func (m *Match) GroupByName(name string) *Group {
+ num := m.regex.GroupNumberFromName(name)
+ if num < 0 {
+ return nil
+ }
+ return m.GroupByNumber(num)
+}
+
+// GroupByNumber returns a group based on the number of the group, or nil if the group number does not exist
+func (m *Match) GroupByNumber(num int) *Group {
+ // check our sparse map
+ if m.sparseCaps != nil {
+ if newNum, ok := m.sparseCaps[num]; ok {
+ num = newNum
+ }
+ }
+ if num >= len(m.matchcount) || num < 0 {
+ return nil
+ }
+
+ if num == 0 {
+ return &m.Group
+ }
+
+ m.populateOtherGroups()
+
+ return &m.otherGroups[num-1]
+}
+
+// Groups returns all the capture groups, starting with group 0 (the full match)
+func (m *Match) Groups() []Group {
+ m.populateOtherGroups()
+ g := make([]Group, len(m.otherGroups)+1)
+ g[0] = m.Group
+ copy(g[1:], m.otherGroups)
+ return g
+}
+
+func (m *Match) populateOtherGroups() {
+ // Construct all the Group objects first time called
+ if m.otherGroups == nil {
+ m.otherGroups = make([]Group, len(m.matchcount)-1)
+ for i := 0; i < len(m.otherGroups); i++ {
+ m.otherGroups[i] = newGroup(m.regex.GroupNameFromNumber(i+1), m.text, m.matches[i+1], m.matchcount[i+1])
+ }
+ }
+}
+
+func (m *Match) groupValueAppendToBuf(groupnum int, buf *bytes.Buffer) {
+ c := m.matchcount[groupnum]
+ if c == 0 {
+ return
+ }
+
+ matches := m.matches[groupnum]
+
+ index := matches[(c-1)*2]
+ last := index + matches[(c*2)-1]
+
+ for ; index < last; index++ {
+ buf.WriteRune(m.text[index])
+ }
+}
+
+func newGroup(name string, text []rune, caps []int, capcount int) Group {
+ g := Group{}
+ g.text = text
+ if capcount > 0 {
+ g.Index = caps[(capcount-1)*2]
+ g.Length = caps[(capcount*2)-1]
+ }
+ g.Name = name
+ g.Captures = make([]Capture, capcount)
+ for i := 0; i < capcount; i++ {
+ g.Captures[i] = Capture{
+ text: text,
+ Index: caps[i*2],
+ Length: caps[i*2+1],
+ }
+ }
+ //log.Printf("newGroup! capcount %v, %+v", capcount, g)
+
+ return g
+}
+
+func (m *Match) dump() string {
+ buf := &bytes.Buffer{}
+ buf.WriteRune('\n')
+ if len(m.sparseCaps) > 0 {
+ for k, v := range m.sparseCaps {
+ fmt.Fprintf(buf, "Slot %v -> %v\n", k, v)
+ }
+ }
+
+ for i, g := range m.Groups() {
+ fmt.Fprintf(buf, "Group %v (%v), %v caps:\n", i, g.Name, len(g.Captures))
+
+ for _, c := range g.Captures {
+ fmt.Fprintf(buf, " (%v, %v) %v\n", c.Index, c.Length, c.String())
+ }
+ }
+ /*
+ for i := 0; i < len(m.matchcount); i++ {
+ fmt.Fprintf(buf, "\nGroup %v (%v):\n", i, m.regex.GroupNameFromNumber(i))
+
+ for j := 0; j < m.matchcount[i]; j++ {
+ text := ""
+
+ if m.matches[i][j*2] >= 0 {
+ start := m.matches[i][j*2]
+ text = m.text[start : start+m.matches[i][j*2+1]]
+ }
+
+ fmt.Fprintf(buf, " (%v, %v) %v\n", m.matches[i][j*2], m.matches[i][j*2+1], text)
+ }
+ }
+ */
+ return buf.String()
+}