Update libkv dependency

vendor/golang.org/x/text/unicode/norm/composition.go

@@ -33,17 +33,9 @@ const (
 // streamSafe implements the policy of when a CGJ should be inserted.
 type streamSafe uint8
 
-// mkStreamSafe is a shorthand for declaring a streamSafe var and calling
-// first on it.
-func mkStreamSafe(p Properties) streamSafe {
-	return streamSafe(p.nTrailingNonStarters())
-}
-
-// first inserts the first rune of a segment.
+// first inserts the first rune of a segment. It is a faster version of next if
+// it is known p represents the first rune in a segment.
 func (ss *streamSafe) first(p Properties) {
-	if *ss != 0 {
-		panic("!= 0")
-	}
 	*ss = streamSafe(p.nTrailingNonStarters())
 }
 
@@ -66,7 +58,7 @@ func (ss *streamSafe) next(p Properties) ssState {
 	// be a non-starter. Note that it always hold that if nLead > 0 then
 	// nLead == nTrail.
 	if n == 0 {
-		*ss = 0
+		*ss = streamSafe(p.nTrailingNonStarters())
 		return ssStarter
 	}
 	return ssSuccess
@@ -142,7 +134,6 @@ func (rb *reorderBuffer) setFlusher(out []byte, f func(*reorderBuffer) bool) {
 func (rb *reorderBuffer) reset() {
 	rb.nrune = 0
 	rb.nbyte = 0
-	rb.ss = 0
 }
 
 func (rb *reorderBuffer) doFlush() bool {
@@ -257,6 +248,9 @@ func (rb *reorderBuffer) insertUnsafe(src input, i int, info Properties) {
 // It flushes the buffer on each new segment start.
 func (rb *reorderBuffer) insertDecomposed(dcomp []byte) insertErr {
 	rb.tmpBytes.setBytes(dcomp)
+	// As the streamSafe accounting already handles the counting for modifiers,
+	// we don't have to call next. However, we do need to keep the accounting
+	// intact when flushing the buffer.
 	for i := 0; i < len(dcomp); {
 		info := rb.f.info(rb.tmpBytes, i)
 		if info.BoundaryBefore() && rb.nrune > 0 && !rb.doFlush() {

vendor/golang.org/x/text/unicode/norm/forminfo.go

@@ -10,7 +10,7 @@ package norm
 // and its corresponding decomposing form share the same trie.  Each trie maps
 // a rune to a uint16. The values take two forms.  For v >= 0x8000:
 //   bits
-//   15:    1 (inverse of NFD_QD bit of qcInfo)
+//   15:    1 (inverse of NFD_QC bit of qcInfo)
 //   13..7: qcInfo (see below). isYesD is always true (no decompostion).
 //    6..0: ccc (compressed CCC value).
 // For v < 0x8000, the respective rune has a decomposition and v is an index
@@ -56,28 +56,31 @@ type formInfo struct {
 	nextMain                 iterFunc
 }
 
-var formTable []*formInfo
-
-func init() {
-	formTable = make([]*formInfo, 4)
-
-	for i := range formTable {
-		f := &formInfo{}
-		formTable[i] = f
-		f.form = Form(i)
-		if Form(i) == NFKD || Form(i) == NFKC {
-			f.compatibility = true
-			f.info = lookupInfoNFKC
-		} else {
-			f.info = lookupInfoNFC
-		}
-		f.nextMain = nextDecomposed
-		if Form(i) == NFC || Form(i) == NFKC {
-			f.nextMain = nextComposed
-			f.composing = true
-		}
-	}
-}
+var formTable = []*formInfo{{
+	form:          NFC,
+	composing:     true,
+	compatibility: false,
+	info:          lookupInfoNFC,
+	nextMain:      nextComposed,
+}, {
+	form:          NFD,
+	composing:     false,
+	compatibility: false,
+	info:          lookupInfoNFC,
+	nextMain:      nextDecomposed,
+}, {
+	form:          NFKC,
+	composing:     true,
+	compatibility: true,
+	info:          lookupInfoNFKC,
+	nextMain:      nextComposed,
+}, {
+	form:          NFKD,
+	composing:     false,
+	compatibility: true,
+	info:          lookupInfoNFKC,
+	nextMain:      nextDecomposed,
+}}
 
 // We do not distinguish between boundaries for NFC, NFD, etc. to avoid
 // unexpected behavior for the user.  For example, in NFD, there is a boundary

vendor/golang.org/x/text/unicode/norm/input.go

@@ -90,16 +90,20 @@ func (in *input) charinfoNFKC(p int) (uint16, int) {
 }
 
 func (in *input) hangul(p int) (r rune) {
+	var size int
 	if in.bytes == nil {
 		if !isHangulString(in.str[p:]) {
 			return 0
 		}
-		r, _ = utf8.DecodeRuneInString(in.str[p:])
+		r, size = utf8.DecodeRuneInString(in.str[p:])
 	} else {
 		if !isHangul(in.bytes[p:]) {
 			return 0
 		}
-		r, _ = utf8.DecodeRune(in.bytes[p:])
+		r, size = utf8.DecodeRune(in.bytes[p:])
+	}
+	if size != hangulUTF8Size {
+		return 0
 	}
 	return r
 }

vendor/golang.org/x/text/unicode/norm/iter.go

@@ -41,6 +41,7 @@ func (i *Iter) Init(f Form, src []byte) {
 	i.next = i.rb.f.nextMain
 	i.asciiF = nextASCIIBytes
 	i.info = i.rb.f.info(i.rb.src, i.p)
+	i.rb.ss.first(i.info)
 }
 
 // InitString initializes i to iterate over src after normalizing it to Form f.
@@ -56,11 +57,12 @@ func (i *Iter) InitString(f Form, src string) {
 	i.next = i.rb.f.nextMain
 	i.asciiF = nextASCIIString
 	i.info = i.rb.f.info(i.rb.src, i.p)
+	i.rb.ss.first(i.info)
 }
 
 // Seek sets the segment to be returned by the next call to Next to start
 // at position p.  It is the responsibility of the caller to set p to the
-// start of a UTF8 rune.
+// start of a segment.
 func (i *Iter) Seek(offset int64, whence int) (int64, error) {
 	var abs int64
 	switch whence {
@@ -84,6 +86,7 @@ func (i *Iter) Seek(offset int64, whence int) (int64, error) {
 	i.multiSeg = nil
 	i.next = i.rb.f.nextMain
 	i.info = i.rb.f.info(i.rb.src, i.p)
+	i.rb.ss.first(i.info)
 	return abs, nil
 }
 
@@ -161,6 +164,7 @@ func nextHangul(i *Iter) []byte {
 	if next >= i.rb.nsrc {
 		i.setDone()
 	} else if i.rb.src.hangul(next) == 0 {
+		i.rb.ss.next(i.info)
 		i.info = i.rb.f.info(i.rb.src, i.p)
 		i.next = i.rb.f.nextMain
 		return i.next(i)
@@ -204,12 +208,10 @@ func nextMultiNorm(i *Iter) []byte {
 		if info.BoundaryBefore() {
 			i.rb.compose()
 			seg := i.buf[:i.rb.flushCopy(i.buf[:])]
-			i.rb.ss.first(info)
 			i.rb.insertUnsafe(input{bytes: d}, j, info)
 			i.multiSeg = d[j+int(info.size):]
 			return seg
 		}
-		i.rb.ss.next(info)
 		i.rb.insertUnsafe(input{bytes: d}, j, info)
 		j += int(info.size)
 	}
@@ -222,9 +224,9 @@ func nextMultiNorm(i *Iter) []byte {
 func nextDecomposed(i *Iter) (next []byte) {
 	outp := 0
 	inCopyStart, outCopyStart := i.p, 0
-	ss := mkStreamSafe(i.info)
 	for {
 		if sz := int(i.info.size); sz <= 1 {
+			i.rb.ss = 0
 			p := i.p
 			i.p++ // ASCII or illegal byte.  Either way, advance by 1.
 			if i.p >= i.rb.nsrc {
@@ -243,6 +245,8 @@ func nextDecomposed(i *Iter) (next []byte) {
 			p := outp + len(d)
 			if outp > 0 {
 				i.rb.src.copySlice(i.buf[outCopyStart:], inCopyStart, i.p)
+				// TODO: this condition should not be possible, but we leave it
+				// in for defensive purposes.
 				if p > len(i.buf) {
 					return i.buf[:outp]
 				}
@@ -266,7 +270,7 @@ func nextDecomposed(i *Iter) (next []byte) {
 			} else {
 				i.info = i.rb.f.info(i.rb.src, i.p)
 			}
-			switch ss.next(i.info) {
+			switch i.rb.ss.next(i.info) {
 			case ssOverflow:
 				i.next = nextCGJDecompose
 				fallthrough
@@ -309,7 +313,7 @@ func nextDecomposed(i *Iter) (next []byte) {
 		}
 		prevCC := i.info.tccc
 		i.info = i.rb.f.info(i.rb.src, i.p)
-		if v := ss.next(i.info); v == ssStarter {
+		if v := i.rb.ss.next(i.info); v == ssStarter {
 			break
 		} else if v == ssOverflow {
 			i.next = nextCGJDecompose
@@ -335,10 +339,6 @@ doNorm:
 
 func doNormDecomposed(i *Iter) []byte {
 	for {
-		if s := i.rb.ss.next(i.info); s == ssOverflow {
-			i.next = nextCGJDecompose
-			break
-		}
 		i.rb.insertUnsafe(i.rb.src, i.p, i.info)
 		if i.p += int(i.info.size); i.p >= i.rb.nsrc {
 			i.setDone()
@@ -348,6 +348,10 @@ func doNormDecomposed(i *Iter) []byte {
 		if i.info.ccc == 0 {
 			break
 		}
+		if s := i.rb.ss.next(i.info); s == ssOverflow {
+			i.next = nextCGJDecompose
+			break
+		}
 	}
 	// new segment or too many combining characters: exit normalization
 	return i.buf[:i.rb.flushCopy(i.buf[:])]
@@ -357,6 +361,7 @@ func nextCGJDecompose(i *Iter) []byte {
 	i.rb.ss = 0
 	i.rb.insertCGJ()
 	i.next = nextDecomposed
+	i.rb.ss.first(i.info)
 	buf := doNormDecomposed(i)
 	return buf
 }
@@ -365,7 +370,6 @@ func nextCGJDecompose(i *Iter) []byte {
 func nextComposed(i *Iter) []byte {
 	outp, startp := 0, i.p
 	var prevCC uint8
-	ss := mkStreamSafe(i.info)
 	for {
 		if !i.info.isYesC() {
 			goto doNorm
@@ -385,11 +389,12 @@ func nextComposed(i *Iter) []byte {
 			i.setDone()
 			break
 		} else if i.rb.src._byte(i.p) < utf8.RuneSelf {
+			i.rb.ss = 0
 			i.next = i.asciiF
 			break
 		}
 		i.info = i.rb.f.info(i.rb.src, i.p)
-		if v := ss.next(i.info); v == ssStarter {
+		if v := i.rb.ss.next(i.info); v == ssStarter {
 			break
 		} else if v == ssOverflow {
 			i.next = nextCGJCompose
@@ -401,8 +406,10 @@ func nextComposed(i *Iter) []byte {
 	}
 	return i.returnSlice(startp, i.p)
 doNorm:
+	// reset to start position
 	i.p = startp
 	i.info = i.rb.f.info(i.rb.src, i.p)
+	i.rb.ss.first(i.info)
 	if i.info.multiSegment() {
 		d := i.info.Decomposition()
 		info := i.rb.f.info(input{bytes: d}, 0)

vendor/golang.org/x/text/unicode/norm/maketables.go

@@ -35,12 +35,9 @@ func main() {
 	computeNonStarterCounts()
 	verifyComputed()
 	printChars()
-	if *test {
-		testDerived()
-		printTestdata()
-	} else {
-		makeTables()
-	}
+	testDerived()
+	printTestdata()
+	makeTables()
 }
 
 var (
@@ -602,6 +599,7 @@ func printCharInfoTables(w io.Writer) int {
 		}
 		index := normalDecomp
 		nTrail := chars[r].nTrailingNonStarters
+		nLead := chars[r].nLeadingNonStarters
 		if tccc > 0 || lccc > 0 || nTrail > 0 {
 			tccc <<= 2
 			tccc |= nTrail
@@ -612,7 +610,7 @@ func printCharInfoTables(w io.Writer) int {
 					index = firstCCC
 				}
 			}
-			if lccc > 0 {
+			if lccc > 0 || nLead > 0 {
 				s += string([]byte{lccc})
 				if index == firstCCC {
 					log.Fatalf("%U: multi-segment decomposition not supported for decompositions with leading CCC != 0", r)

vendor/golang.org/x/text/unicode/norm/normalize.go

@@ -2,13 +2,18 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Note: the file data_test.go that is generated should not be checked in.
 //go:generate go run maketables.go triegen.go
-//go:generate go run maketables.go triegen.go -test
+//go:generate go test -tags test
 
 // Package norm contains types and functions for normalizing Unicode strings.
 package norm // import "golang.org/x/text/unicode/norm"
 
-import "unicode/utf8"
+import (
+	"unicode/utf8"
+
+	"golang.org/x/text/transform"
+)
 
 // A Form denotes a canonical representation of Unicode code points.
 // The Unicode-defined normalization and equivalence forms are:
@@ -263,6 +268,34 @@ func (f Form) QuickSpan(b []byte) int {
 	return n
 }
 
+// Span implements transform.SpanningTransformer. It returns a boundary n such
+// that b[0:n] == f(b[0:n]). It is not guaranteed to return the largest such n.
+func (f Form) Span(b []byte, atEOF bool) (n int, err error) {
+	n, ok := formTable[f].quickSpan(inputBytes(b), 0, len(b), atEOF)
+	if n < len(b) {
+		if !ok {
+			err = transform.ErrEndOfSpan
+		} else {
+			err = transform.ErrShortSrc
+		}
+	}
+	return n, err
+}
+
+// SpanString returns a boundary n such that s[0:n] == f(s[0:n]).
+// It is not guaranteed to return the largest such n.
+func (f Form) SpanString(s string, atEOF bool) (n int, err error) {
+	n, ok := formTable[f].quickSpan(inputString(s), 0, len(s), atEOF)
+	if n < len(s) {
+		if !ok {
+			err = transform.ErrEndOfSpan
+		} else {
+			err = transform.ErrShortSrc
+		}
+	}
+	return n, err
+}
+
 // quickSpan returns a boundary n such that src[0:n] == f(src[0:n]) and
 // whether any non-normalized parts were found. If atEOF is false, n will
 // not point past the last segment if this segment might be become
@@ -291,7 +324,6 @@ func (f *formInfo) quickSpan(src input, i, end int, atEOF bool) (n int, ok bool)
 		// have an overflow for runes that are starters (e.g. with U+FF9E).
 		switch ss.next(info) {
 		case ssStarter:
-			ss.first(info)
 			lastSegStart = i
 		case ssOverflow:
 			return lastSegStart, false
@@ -321,7 +353,7 @@ func (f *formInfo) quickSpan(src input, i, end int, atEOF bool) (n int, ok bool)
 	return lastSegStart, false
 }
 
-// QuickSpanString returns a boundary n such that b[0:n] == f(s[0:n]).
+// QuickSpanString returns a boundary n such that s[0:n] == f(s[0:n]).
 // It is not guaranteed to return the largest such n.
 func (f Form) QuickSpanString(s string) int {
 	n, _ := formTable[f].quickSpan(inputString(s), 0, len(s), true)
@@ -408,6 +440,8 @@ func (f Form) nextBoundary(src input, nsrc int, atEOF bool) int {
 			}
 			return -1
 		}
+		// TODO: Using streamSafe to determine the boundary isn't the same as
+		// using BoundaryBefore. Determine which should be used.
 		if s := ss.next(info); s != ssSuccess {
 			return i
 		}
@@ -472,15 +506,14 @@ func decomposeSegment(rb *reorderBuffer, sp int, atEOF bool) int {
 	if info.size == 0 {
 		return 0
 	}
-	if rb.nrune > 0 {
-		if s := rb.ss.next(info); s == ssStarter {
-			goto end
-		} else if s == ssOverflow {
-			rb.insertCGJ()
+	if s := rb.ss.next(info); s == ssStarter {
+		// TODO: this could be removed if we don't support merging.
+		if rb.nrune > 0 {
 			goto end
 		}
-	} else {
-		rb.ss.first(info)
+	} else if s == ssOverflow {
+		rb.insertCGJ()
+		goto end
 	}
 	if err := rb.insertFlush(rb.src, sp, info); err != iSuccess {
 		return int(err)

vendor/golang.org/x/text/unicode/norm/readwriter.go

@@ -112,7 +112,6 @@ func (r *normReader) Read(p []byte) (int, error) {
 			}
 		}
 	}
-	panic("should not reach here")
 }
 
 // Reader returns a new reader that implements Read