mirror of
https://github.com/golang/go
synced 2024-11-21 15:14:43 -07:00
exp/norm: added Reader and Writer and bug fixes to support these.
Needed to ensure that finding the last boundary does not result in O(n^2)-like behavior. Now prevents lookbacks beyond 31 characters across the board (starter + 30 non-starters). composition.go: - maxCombiningCharacters now means exactly that. - Bug fix. - Small performance improvement/ made code consistent with other code. forminfo.go: - Bug fix: ccc needs to be 0 for inert runes. normalize.go: - A few bug fixes. - Limit the amount of combining characters considered in FirstBoundary. - Ditto for LastBoundary. - Changed semantics of LastBoundary to not consider trailing illegal runes a boundary as long as adding bytes might still make them legal. trie.go: - As utf8.UTFMax is 4, we should treat UTF-8 encodings of size 5 or greater as illegal. This has no impact on the normalization process, but it prevents buffer overflows where we expect at most UTFMax bytes. R=r CC=golang-dev https://golang.org/cl/4963041
This commit is contained in:
Marcel van Lohuizen
parent
b349cd2b0a
commit
2517143957
@ -9,6 +9,7 @@ GOFILES=\
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composition.go\
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forminfo.go\
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normalize.go\
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readwriter.go\
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tables.go\
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trie.go\
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@ -7,12 +7,13 @@ package norm
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import "utf8"
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const (
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maxCombiningChars = 30 + 2 // +2 to hold CGJ and Hangul overflow.
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maxCombiningChars = 30
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maxBufferSize = maxCombiningChars + 2 // +1 to hold starter +1 to hold CGJ
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maxBackRunes = maxCombiningChars - 1
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maxNFCExpansion = 3 // NFC(0x1D160)
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maxNFKCExpansion = 18 // NFKC(0xFDFA)
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maxByteBufferSize = utf8.UTFMax * maxCombiningChars // 128
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maxByteBufferSize = utf8.UTFMax * maxBufferSize // 128
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)
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// reorderBuffer is used to normalize a single segment. Characters inserted with
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@ -21,10 +22,10 @@ const (
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// the UTF-8 characters in order. Only the rune array is maintained in sorted
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// order. flush writes the resulting segment to a byte array.
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type reorderBuffer struct {
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rune [maxCombiningChars]runeInfo // Per character info.
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byte [maxByteBufferSize]byte // UTF-8 buffer. Referenced by runeInfo.pos.
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nrune int // Number of runeInfos.
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nbyte uint8 // Number or bytes.
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rune [maxBufferSize]runeInfo // Per character info.
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byte [maxByteBufferSize]byte // UTF-8 buffer. Referenced by runeInfo.pos.
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nrune int // Number of runeInfos.
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nbyte uint8 // Number or bytes.
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f formInfo
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}
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@ -47,10 +48,10 @@ func (rb *reorderBuffer) flush(out []byte) []byte {
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// insertOrdered inserts a rune in the buffer, ordered by Canonical Combining Class.
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// It returns false if the buffer is not large enough to hold the rune.
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// It is used internally by insert.
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// It is used internally by insert and insertString only.
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func (rb *reorderBuffer) insertOrdered(info runeInfo) bool {
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n := rb.nrune
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if n >= maxCombiningChars {
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if n >= maxCombiningChars+1 {
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return false
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}
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b := rb.rune[:]
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@ -92,6 +93,7 @@ func (rb *reorderBuffer) insert(src []byte, info runeInfo) bool {
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i = end
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}
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} else {
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// insertOrder changes nbyte
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pos := rb.nbyte
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if !rb.insertOrdered(info) {
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return false
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@ -121,10 +123,12 @@ func (rb *reorderBuffer) insertString(src string, info runeInfo) bool {
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i = end
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}
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} else {
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copy(rb.byte[rb.nbyte:], src[:info.size])
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// insertOrder changes nbyte
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pos := rb.nbyte
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if !rb.insertOrdered(info) {
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return false
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}
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copy(rb.byte[pos:], src[:info.size])
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}
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return true
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}
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@ -305,9 +309,12 @@ func (rb *reorderBuffer) compose() {
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// blocked from S if and only if there is some character B between S
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// and C, and either B is a starter or it has the same or higher
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// combining class as C."
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bn := rb.nrune
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if bn == 0 {
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return
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}
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k := 1
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b := rb.rune[:]
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bn := rb.nrune
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for s, i := 0, 1; i < bn; i++ {
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if isJamoVT(rb.bytesAt(i)) {
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// Redo from start in Hangul mode. Necessary to support
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@ -89,7 +89,7 @@ func compBoundaryBefore(f *formInfo, info runeInfo) bool {
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func compBoundaryAfter(f *formInfo, info runeInfo) bool {
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// This misses values where the last char in a decomposition is a
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// boundary such as Hangul with JamoT.
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return info.flags.isInert()
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return info.isInert()
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}
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// We pack quick check data in 4 bits:
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@ -108,12 +108,15 @@ func (i qcInfo) isNoC() bool { return i&0x6 == 0x2 }
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func (i qcInfo) isMaybe() bool { return i&0x4 != 0 }
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func (i qcInfo) isYesD() bool { return i&0x1 == 0 }
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func (i qcInfo) isNoD() bool { return i&0x1 != 0 }
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func (i qcInfo) isInert() bool { return i&0xf == 0 }
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func (i qcInfo) combinesForward() bool { return i&0x8 != 0 }
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func (i qcInfo) combinesBackward() bool { return i&0x4 != 0 } // == isMaybe
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func (i qcInfo) hasDecomposition() bool { return i&0x1 != 0 } // == isNoD
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func (r runeInfo) isInert() bool {
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return r.flags&0xf == 0 && r.ccc == 0
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}
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// Wrappers for tables.go
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// The 16-bit value of the decompostion tries is an index into a byte
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@ -98,7 +98,7 @@ func (f Form) IsNormalString(s string) bool {
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// have been dropped.
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func patchTail(rb *reorderBuffer, buf []byte) ([]byte, int) {
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info, p := lastRuneStart(&rb.f, buf)
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if p == -1 {
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if p == -1 || info.size == 0 {
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return buf, 0
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}
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end := p + int(info.size)
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@ -129,7 +129,10 @@ func (f Form) Append(out []byte, src ...byte) []byte {
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}
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fd := formTable[f]
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rb := &reorderBuffer{f: *fd}
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return doAppend(rb, out, src)
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}
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func doAppend(rb *reorderBuffer, out, src []byte) []byte {
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doMerge := len(out) > 0
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p := 0
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if !utf8.RuneStart(src[0]) {
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@ -145,20 +148,24 @@ func (f Form) Append(out []byte, src ...byte) []byte {
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out = decomposeToLastBoundary(rb, buf) // force decomposition
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}
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}
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fd := &rb.f
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if doMerge {
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var info runeInfo
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if p < len(src[p:]) {
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if p < len(src) {
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info = fd.info(src[p:])
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if p == 0 && !fd.boundaryBefore(fd, info) {
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out = decomposeToLastBoundary(rb, out)
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}
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}
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if info.size == 0 {
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if info.size == 0 || fd.boundaryBefore(fd, info) {
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if fd.composing {
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rb.compose()
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}
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// Append incomplete UTF-8 encoding.
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return append(rb.flush(out), src[p:]...)
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out = rb.flush(out)
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if info.size == 0 {
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// Append incomplete UTF-8 encoding.
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return append(out, src[p:]...)
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}
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}
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}
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if rb.nrune == 0 {
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@ -249,8 +256,11 @@ func (f Form) FirstBoundary(b []byte) int {
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}
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fd := formTable[f]
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info := fd.info(b[i:])
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for info.size != 0 && !fd.boundaryBefore(fd, info) {
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for n := 0; info.size != 0 && !fd.boundaryBefore(fd, info); {
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i += int(info.size)
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if n++; n >= maxCombiningChars {
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return i
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}
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if i >= len(b) {
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if !fd.boundaryAfter(fd, info) {
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return -1
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@ -274,29 +284,42 @@ func (f Form) FirstBoundaryInString(s string) (i int, ok bool) {
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// LastBoundary returns the position i of the last boundary in b
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// or -1 if b contains no boundary.
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func (f Form) LastBoundary(b []byte) int {
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fd := formTable[f]
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return lastBoundary(formTable[f], b)
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}
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func lastBoundary(fd *formInfo, b []byte) int {
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i := len(b)
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if i == 0 {
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info, p := lastRuneStart(fd, b)
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if p == -1 {
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return -1
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}
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info, p := lastRuneStart(fd, b)
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if int(info.size) != len(b)-p {
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if p != -1 {
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if info.size == 0 { // ends with incomplete rune
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if p == 0 { // starts wtih incomplete rune
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return -1
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}
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i = p
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info, p = lastRuneStart(fd, b[:i])
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if p == -1 { // incomplete UTF-8 encoding or non-starter bytes without a starter
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return i
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}
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return -1
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}
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if p+int(info.size) != i { // trailing non-starter bytes: illegal UTF-8
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return i
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}
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if fd.boundaryAfter(fd, info) {
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return i
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}
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i = p
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for i >= 0 && !fd.boundaryBefore(fd, info) {
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for n := 0; i >= 0 && !fd.boundaryBefore(fd, info); {
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info, p = lastRuneStart(fd, b[:i])
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if int(info.size) != i-p {
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if p != -1 {
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return i
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if n++; n >= maxCombiningChars {
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return len(b)
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}
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if p+int(info.size) != i {
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if p == -1 { // no boundary found
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return -1
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}
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return -1
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return i // boundary after an illegal UTF-8 encoding
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}
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i = p
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}
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@ -349,12 +372,13 @@ func lastRuneStart(fd *formInfo, buf []byte) (runeInfo, int) {
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// decomposeToLastBoundary finds an open segment at the end of the buffer
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// and scans it into rb. Returns the buffer minus the last segment.
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func decomposeToLastBoundary(rb *reorderBuffer, buf []byte) []byte {
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info, i := lastRuneStart(&rb.f, buf)
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fd := &rb.f
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info, i := lastRuneStart(fd, buf)
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if int(info.size) != len(buf)-i {
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// illegal trailing continuation bytes
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return buf
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}
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if rb.f.boundaryAfter(&rb.f, info) {
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if rb.f.boundaryAfter(fd, info) {
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return buf
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}
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var add [maxBackRunes]runeInfo // stores runeInfo in reverse order
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@ -362,8 +386,8 @@ func decomposeToLastBoundary(rb *reorderBuffer, buf []byte) []byte {
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padd := 1
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n := 1
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p := len(buf) - int(info.size)
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for ; p >= 0 && !rb.f.boundaryBefore(&rb.f, info); p -= int(info.size) {
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info, i = lastRuneStart(&rb.f, buf[:p])
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for ; p >= 0 && !rb.f.boundaryBefore(fd, info); p -= int(info.size) {
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info, i = lastRuneStart(fd, buf[:p])
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if int(info.size) != p-i {
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break
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}
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@ -53,9 +53,7 @@ var decomposeSegmentTests = []PositionTest{
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{"\u00C0", 2, "A\u0300"},
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{"\u00C0b", 2, "A\u0300"},
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// long
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{strings.Repeat("\u0300", 32), 64, strings.Repeat("\u0300", 32)},
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// overflow
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{strings.Repeat("\u0300", 33), 64, strings.Repeat("\u0300", 32)},
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{strings.Repeat("\u0300", 31), 62, strings.Repeat("\u0300", 31)},
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// ends with incomplete UTF-8 encoding
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{"\xCC", 0, ""},
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{"\u0300\xCC", 2, "\u0300"},
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@ -86,6 +84,10 @@ var firstBoundaryTests = []PositionTest{
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{"\u110B\u1173\u11B7", 0, ""},
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{"\u1161\u110B\u1173\u11B7", 3, ""},
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{"\u1173\u11B7\u1103\u1161", 6, ""},
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// too many combining characters.
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{strings.Repeat("\u0300", maxCombiningChars-1), -1, ""},
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{strings.Repeat("\u0300", maxCombiningChars), 60, ""},
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{strings.Repeat("\u0300", maxCombiningChars+1), 60, ""},
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}
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func firstBoundary(rb *reorderBuffer, s string) int {
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@ -105,6 +107,7 @@ var decomposeToLastTests = []PositionTest{
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{"a", 0, "a"},
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{"a\u0301a", 3, "a"},
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{"a\u0301\u03B9", 3, "\u03B9"},
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{"a\u0327", 0, "a\u0327"},
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// illegal runes
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{"\xFF", 1, ""},
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{"aa\xFF", 3, ""},
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@ -123,7 +126,7 @@ var decomposeToLastTests = []PositionTest{
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{"a\u00C0", 1, "A\u0300"},
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// decomposing
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{"a\u0300\uFDC0", 3, "\u0645\u062C\u064A"},
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{"\uFDC0" + strings.Repeat("\u0300", 28), 0, "\u0645\u062C\u064A" + strings.Repeat("\u0300", 28)},
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{"\uFDC0" + strings.Repeat("\u0300", 26), 0, "\u0645\u062C\u064A" + strings.Repeat("\u0300", 26)},
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// Hangul
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{"a\u1103", 1, "\u1103"},
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{"a\u110B", 1, "\u110B"},
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@ -138,7 +141,7 @@ var decomposeToLastTests = []PositionTest{
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{"다음음", 6, "\u110B\u1173\u11B7"},
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{"음다다", 6, "\u1103\u1161"},
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// buffer overflow
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{"a" + strings.Repeat("\u0300", 35), 9, strings.Repeat("\u0300", 31)},
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{"a" + strings.Repeat("\u0300", 30), 3, strings.Repeat("\u0300", 29)},
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{"\uFDFA" + strings.Repeat("\u0300", 14), 3, strings.Repeat("\u0300", 14)},
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// weird UTF-8
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{"a\u0300\u11B7", 0, "a\u0300\u11B7"},
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@ -165,13 +168,21 @@ var lastBoundaryTests = []PositionTest{
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{"a\xff\u0300", 1, ""},
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{"\xc0\x80\x80", 3, ""},
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{"\xc0\x80\x80\u0300", 3, ""},
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{"\xc0", 1, ""},
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// ends with incomplete UTF-8 encoding
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{"\xCC", -1, ""},
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{"\xE0\x80", -1, ""},
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{"\xF0\x80\x80", -1, ""},
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{"a\xCC", 0, ""},
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{"\x80\xCC", 1, ""},
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{"\xCC\xCC", 1, ""},
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// ends with combining characters
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{"a\u0300\u0301", 0, ""},
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{"aaaa\u0300\u0301", 3, ""},
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{"\u0300a\u0300\u0301", 2, ""},
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{"\u00C0", 0, ""},
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{"a\u00C0", 1, ""},
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// decomposition may recombine
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{"\u0226", 0, ""},
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// no boundary
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{"", -1, ""},
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{"\u0300\u0301", -1, ""},
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@ -183,16 +194,18 @@ var lastBoundaryTests = []PositionTest{
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{"다", 0, ""},
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{"\u1103\u1161\u110B\u1173\u11B7", 6, ""},
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{"\u110B\u1173\u11B7\u1103\u1161", 9, ""},
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// ends with incomplete UTF-8 encoding
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{"\xCC", 1, ""},
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// too many combining characters.
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{strings.Repeat("\u0300", maxCombiningChars-1), -1, ""},
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{strings.Repeat("\u0300", maxCombiningChars), 60, ""},
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{strings.Repeat("\u0300", maxCombiningChars+1), 62, ""},
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}
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func lastBoundary(rb *reorderBuffer, s string) int {
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func lastBoundaryF(rb *reorderBuffer, s string) int {
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return rb.f.form.LastBoundary([]byte(s))
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}
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func TestLastBoundary(t *testing.T) {
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runPosTests(t, "TestLastBoundary", NFC, lastBoundary, lastBoundaryTests)
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runPosTests(t, "TestLastBoundary", NFC, lastBoundaryF, lastBoundaryTests)
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}
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var quickSpanTests = []PositionTest{
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@ -342,8 +355,26 @@ func runAppendTests(t *testing.T, name string, f Form, fn appendFunc, tests []Ap
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for i, test := range tests {
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out := []byte(test.left)
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out = fn(f, out, test.right)
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if string(out) != test.out {
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t.Errorf("%s:%d: result is %X; want %X", name, i, []int(string(out)), []int(test.out))
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outs := string(out)
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if len(outs) != len(test.out) {
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t.Errorf("%s:%d: length is %d; want %d", name, i, len(outs), len(test.out))
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}
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if outs != test.out {
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// Find first rune that differs and show context.
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ir := []int(outs)
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ig := []int(test.out)
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for j := 0; j < len(ir) && j < len(ig); j++ {
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if ir[j] == ig[j] {
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continue
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}
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if j -= 3; j < 0 {
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j = 0
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}
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for e := j + 7; j < e && j < len(ir) && j < len(ig); j++ {
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t.Errorf("%s:%d: runeAt(%d) = %U; want %U", name, i, j, ir[j], ig[j])
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}
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break
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}
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}
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}
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}
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@ -357,10 +388,14 @@ var appendTests = []AppendTest{
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// segment split across buffers
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{"", "a\u0300b", "\u00E0b"},
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{"a", "\u0300b", "\u00E0b"},
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{"a", "\u0300\u0316", "\u00E0\u0316"},
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{"a", "\u0316\u0300", "\u00E0\u0316"},
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{"a", "\u0300a\u0300", "\u00E0\u00E0"},
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{"a", "\u0300a\u0300a\u0300", "\u00E0\u00E0\u00E0"},
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{"a", "\u0300aaa\u0300aaa\u0300", "\u00E0aa\u00E0aa\u00E0"},
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{"a\u0300", "\u0316", "\u00E0\u0316"},
|
||||
{"a\u0300", "\u0327", "\u00E0\u0327"},
|
||||
{"a\u0327", "\u0300", "\u00E0\u0327"},
|
||||
{"a\u0316", "\u0300", "\u00E0\u0316"},
|
||||
{"\u0041\u0307", "\u0304", "\u01E0"},
|
||||
// Hangul
|
||||
{"", "\u110B\u1173", "\uC73C"},
|
||||
@ -378,10 +413,12 @@ var appendTests = []AppendTest{
|
||||
{"a\xCC", "\x80a\u0300", "\u00E0\u00E0"},
|
||||
{"a\xCC", "\x80\x80", "\u00E0\x80"},
|
||||
{"a\xCC", "\x80\xCC", "\u00E0\xCC"},
|
||||
{"a\u0316\xCC", "\x80a\u0316\u0300", "\u00E0\u0316\u00E0\u0316"},
|
||||
// ending in incomplete UTF-8 encoding
|
||||
{"", "\xCC", "\xCC"},
|
||||
{"a", "\xCC", "a\xCC"},
|
||||
{"a", "b\xCC", "ab\xCC"},
|
||||
{"\u0226", "\xCC", "\u0226\xCC"},
|
||||
// illegal runes
|
||||
{"", "\x80", "\x80"},
|
||||
{"", "\x80\x80\x80", "\x80\x80\x80"},
|
||||
@ -394,12 +431,16 @@ var appendTests = []AppendTest{
|
||||
{"", strings.Repeat("\x80", 33), strings.Repeat("\x80", 33)},
|
||||
{strings.Repeat("\x80", 33), "", strings.Repeat("\x80", 33)},
|
||||
{strings.Repeat("\x80", 33), strings.Repeat("\x80", 33), strings.Repeat("\x80", 66)},
|
||||
{"", strings.Repeat("\u0300", 33), strings.Repeat("\u0300", 33)},
|
||||
// overflow of combining characters
|
||||
{strings.Repeat("\u0300", 33), "", strings.Repeat("\u0300", 33)},
|
||||
{strings.Repeat("\u0300", 33), strings.Repeat("\u0300", 33), strings.Repeat("\u0300", 66)},
|
||||
// weird UTF-8
|
||||
{"\u00E0\xE1", "\x86", "\u00E0\xE1\x86"},
|
||||
{"a\u0300\u11B7", "\u0300", "\u00E0\u11B7\u0300"},
|
||||
{"a\u0300\u11B7\u0300", "\u0300", "\u00E0\u11B7\u0300\u0300"},
|
||||
{"\u0300", "\xF8\x80\x80\x80\x80\u0300", "\u0300\xF8\x80\x80\x80\x80\u0300"},
|
||||
{"\u0300", "\xFC\x80\x80\x80\x80\x80\u0300", "\u0300\xFC\x80\x80\x80\x80\x80\u0300"},
|
||||
{"\xF8\x80\x80\x80\x80\u0300", "\u0300", "\xF8\x80\x80\x80\x80\u0300\u0300"},
|
||||
{"\xFC\x80\x80\x80\x80\x80\u0300", "\u0300", "\xFC\x80\x80\x80\x80\x80\u0300\u0300"},
|
||||
}
|
||||
|
||||
func appendF(f Form, out []byte, s string) []byte {
|
||||
|
||||
121
src/pkg/exp/norm/readwriter.go
Normal file
121
src/pkg/exp/norm/readwriter.go
Normal file
@ -0,0 +1,121 @@
|
||||
// Copyright 2011 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package norm
|
||||
|
||||
import (
|
||||
"io"
|
||||
"os"
|
||||
)
|
||||
|
||||
type normWriter struct {
|
||||
rb reorderBuffer
|
||||
w io.Writer
|
||||
buf []byte
|
||||
}
|
||||
|
||||
// Write implements the standard write interface. If the last characters are
|
||||
// not at a normalization boundary, the bytes will be buffered for the next
|
||||
// write. The remaining bytes will be written on close.
|
||||
func (w *normWriter) Write(data []byte) (n int, err os.Error) {
|
||||
// Process data in pieces to keep w.buf size bounded.
|
||||
const chunk = 4000
|
||||
|
||||
for len(data) > 0 {
|
||||
// Normalize into w.buf.
|
||||
m := len(data)
|
||||
if m > chunk {
|
||||
m = chunk
|
||||
}
|
||||
w.buf = doAppend(&w.rb, w.buf, data[:m])
|
||||
data = data[m:]
|
||||
n += m
|
||||
|
||||
// Write out complete prefix, save remainder.
|
||||
// Note that lastBoundary looks back at most 30 runes.
|
||||
i := lastBoundary(&w.rb.f, w.buf)
|
||||
if i == -1 {
|
||||
i = 0
|
||||
}
|
||||
if i > 0 {
|
||||
if _, err = w.w.Write(w.buf[:i]); err != nil {
|
||||
break
|
||||
}
|
||||
bn := copy(w.buf, w.buf[i:])
|
||||
w.buf = w.buf[:bn]
|
||||
}
|
||||
}
|
||||
return n, err
|
||||
}
|
||||
|
||||
// Close forces data that remains in the buffer to be written.
|
||||
func (w *normWriter) Close() os.Error {
|
||||
if len(w.buf) > 0 {
|
||||
_, err := w.w.Write(w.buf)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Writer returns a new writer that implements Write(b)
|
||||
// by writing f(b) to w. The returned writer may use an
|
||||
// an internal buffer to maintain state across Write calls.
|
||||
// Calling its Close method writes any buffered data to w.
|
||||
func (f Form) Writer(w io.Writer) io.WriteCloser {
|
||||
return &normWriter{rb: reorderBuffer{f: *formTable[f]}, w: w}
|
||||
}
|
||||
|
||||
type normReader struct {
|
||||
rb reorderBuffer
|
||||
r io.Reader
|
||||
inbuf []byte
|
||||
outbuf []byte
|
||||
bufStart int
|
||||
lastBoundary int
|
||||
err os.Error
|
||||
}
|
||||
|
||||
// Read implements the standard read interface.
|
||||
func (r *normReader) Read(p []byte) (int, os.Error) {
|
||||
for {
|
||||
if r.lastBoundary-r.bufStart > 0 {
|
||||
n := copy(p, r.outbuf[r.bufStart:r.lastBoundary])
|
||||
r.bufStart += n
|
||||
if r.lastBoundary-r.bufStart > 0 {
|
||||
return n, nil
|
||||
}
|
||||
return n, r.err
|
||||
}
|
||||
if r.err != nil {
|
||||
return 0, r.err
|
||||
}
|
||||
outn := copy(r.outbuf, r.outbuf[r.lastBoundary:])
|
||||
r.outbuf = r.outbuf[0:outn]
|
||||
r.bufStart = 0
|
||||
|
||||
n, err := r.r.Read(r.inbuf)
|
||||
r.err = err // save error for when done with buffer
|
||||
if n > 0 {
|
||||
r.outbuf = doAppend(&r.rb, r.outbuf, r.inbuf[0:n])
|
||||
}
|
||||
if err == os.EOF {
|
||||
r.lastBoundary = len(r.outbuf)
|
||||
} else {
|
||||
r.lastBoundary = lastBoundary(&r.rb.f, r.outbuf)
|
||||
if r.lastBoundary == -1 {
|
||||
r.lastBoundary = 0
|
||||
}
|
||||
}
|
||||
}
|
||||
panic("should not reach here")
|
||||
}
|
||||
|
||||
// Reader returns a new reader that implements Read
|
||||
// by reading data from r and returning f(data).
|
||||
func (f Form) Reader(r io.Reader) io.Reader {
|
||||
const chunk = 4000
|
||||
return &normReader{rb: reorderBuffer{f: *formTable[f]}, r: r, inbuf: make([]byte, chunk)}
|
||||
}
|
||||
69
src/pkg/exp/norm/readwriter_test.go
Normal file
69
src/pkg/exp/norm/readwriter_test.go
Normal file
@ -0,0 +1,69 @@
|
||||
// Copyright 2011 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package norm
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"fmt"
|
||||
"os"
|
||||
"strings"
|
||||
"testing"
|
||||
)
|
||||
|
||||
var ioTests = []AppendTest{
|
||||
{"", strings.Repeat("a\u0316\u0300", 6), strings.Repeat("\u00E0\u0316", 6)},
|
||||
{"", strings.Repeat("a\u0300\u0316", 4000), strings.Repeat("\u00E0\u0316", 4000)},
|
||||
{"", strings.Repeat("\x80\x80", 4000), strings.Repeat("\x80\x80", 4000)},
|
||||
{"", "\u0041\u0307\u0304", "\u01E0"},
|
||||
}
|
||||
|
||||
var bufSizes = []int{1, 2, 3, 4, 5, 6, 7, 8, 100, 101, 102, 103, 4000, 4001, 4002, 4003}
|
||||
|
||||
func readFunc(size int) appendFunc {
|
||||
return func(f Form, out []byte, s string) []byte {
|
||||
out = append(out, []byte(s)...)
|
||||
r := f.Reader(bytes.NewBuffer(out))
|
||||
buf := make([]byte, size)
|
||||
result := []byte{}
|
||||
for n, err := 0, os.Error(nil); err == nil; {
|
||||
n, err = r.Read(buf)
|
||||
result = append(result, buf[:n]...)
|
||||
}
|
||||
return result
|
||||
}
|
||||
}
|
||||
|
||||
func TestReader(t *testing.T) {
|
||||
for _, s := range bufSizes {
|
||||
name := fmt.Sprintf("TestReader%da", s)
|
||||
runAppendTests(t, name, NFKC, readFunc(s), appendTests)
|
||||
name = fmt.Sprintf("TestReader%db", s)
|
||||
runAppendTests(t, name, NFKC, readFunc(s), ioTests)
|
||||
}
|
||||
}
|
||||
|
||||
func writeFunc(size int) appendFunc {
|
||||
return func(f Form, out []byte, s string) []byte {
|
||||
in := append(out, []byte(s)...)
|
||||
result := new(bytes.Buffer)
|
||||
w := f.Writer(result)
|
||||
buf := make([]byte, size)
|
||||
for n := 0; len(in) > 0; in = in[n:] {
|
||||
n = copy(buf, in)
|
||||
_, _ = w.Write(buf[:n])
|
||||
}
|
||||
w.Close()
|
||||
return result.Bytes()
|
||||
}
|
||||
}
|
||||
|
||||
func TestWriter(t *testing.T) {
|
||||
for _, s := range bufSizes {
|
||||
name := fmt.Sprintf("TestWriter%da", s)
|
||||
runAppendTests(t, name, NFKC, writeFunc(s), appendTests)
|
||||
name = fmt.Sprintf("TestWriter%db", s)
|
||||
runAppendTests(t, name, NFKC, writeFunc(s), ioTests)
|
||||
}
|
||||
}
|
||||
@ -86,16 +86,6 @@ func (t *trie) lookup(s []byte) (v uint16, sz int) {
|
||||
}
|
||||
o = uint16(i)<<6 + uint16(c3)&maskx
|
||||
return t.values[o], 4
|
||||
case c0 < t6:
|
||||
if len(s) < 5 {
|
||||
return 0, 0
|
||||
}
|
||||
return 0, 5
|
||||
case c0 < te:
|
||||
if len(s) < 6 {
|
||||
return 0, 0
|
||||
}
|
||||
return 0, 6
|
||||
}
|
||||
// Illegal rune
|
||||
return 0, 1
|
||||
@ -162,16 +152,6 @@ func (t *trie) lookupString(s string) (v uint16, sz int) {
|
||||
}
|
||||
o = uint16(i)<<6 + uint16(c3)&maskx
|
||||
return t.values[o], 4
|
||||
case c0 < t6:
|
||||
if len(s) < 5 {
|
||||
return 0, 0
|
||||
}
|
||||
return 0, 5
|
||||
case c0 < te:
|
||||
if len(s) < 6 {
|
||||
return 0, 0
|
||||
}
|
||||
return 0, 6
|
||||
}
|
||||
// Illegal rune
|
||||
return 0, 1
|
||||
|
||||
@ -32,8 +32,10 @@ var tests = []trietest{
|
||||
{0, []byte{t2}},
|
||||
{0, []byte{t3, tx}},
|
||||
{0, []byte{t4, tx, tx}},
|
||||
{0, []byte{t5, tx, tx, tx}},
|
||||
{0, []byte{t6, tx, tx, tx, tx}},
|
||||
|
||||
// we only support UTF-8 up to utf8.UTFMax bytes (4 bytes)
|
||||
{1, []byte{t5, tx, tx, tx, tx}},
|
||||
{1, []byte{t6, tx, tx, tx, tx, tx}},
|
||||
}
|
||||
|
||||
func mkUtf8(rune int) ([]byte, int) {
|
||||
|
||||
Loading…
Reference in New Issue
Block a user