Merge pull request #621 from charrywanganthony/displaystringutils

Refactor stringutils and fix docker search output form

cli/command/formatter/container.go

@@ -10,7 +10,6 @@ import (
 	"github.com/docker/distribution/reference"
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/pkg/stringid"
-	"github.com/docker/docker/pkg/stringutils"
 	"github.com/docker/go-units"
 )
 
@@ -165,7 +164,7 @@ func (c *containerContext) Image() string {
 func (c *containerContext) Command() string {
 	command := c.c.Command
 	if c.trunc {
-		command = stringutils.Ellipsis(command, 20)
+		command = Ellipsis(command, 20)
 	}
 	return strconv.Quote(command)
 }
@@ -227,7 +226,7 @@ func (c *containerContext) Mounts() string {
 			name = m.Name
 		}
 		if c.trunc {
-			name = stringutils.Ellipsis(name, 15)
+			name = Ellipsis(name, 15)
 		}
 		mounts = append(mounts, name)
 	}

cli/command/formatter/container_test.go

@@ -66,7 +66,7 @@ func TestContainerPsContext(t *testing.T) {
 					Source: "/a/path",
 				},
 			},
-		}, true, "this-is-a-lo...", ctx.Mounts},
+		}, true, "this-is-a-long…", ctx.Mounts},
 		{types.Container{
 			Mounts: []types.MountPoint{
 				{

cli/command/formatter/displayutils.go

@@ -0,0 +1,61 @@
+package formatter
+
+import (
+	"unicode/utf8"
+
+	"golang.org/x/text/width"
+)
+
+// charWidth returns the number of horizontal positions a character occupies,
+// and is used to account for wide characters when displaying strings.
+//
+// In a broad sense, wide characters include East Asian Wide, East Asian Full-width,
+// (when not in East Asian context) see http://unicode.org/reports/tr11/.
+func charWidth(r rune) int {
+	switch width.LookupRune(r).Kind() {
+	case width.EastAsianWide, width.EastAsianFullwidth:
+		return 2
+	default:
+		return 1
+	}
+}
+
+// Ellipsis truncates a string to fit within maxDisplayWidth, and appends ellipsis (…).
+// For maxDisplayWidth of 1 and lower, no ellipsis is appended.
+// For maxDisplayWidth of 1, first char of string will return even if its width > 1.
+func Ellipsis(s string, maxDisplayWidth int) string {
+	if maxDisplayWidth <= 0 {
+		return ""
+	}
+	rs := []rune(s)
+	if maxDisplayWidth == 1 {
+		return string(rs[0])
+	}
+
+	byteLen := len(s)
+	if byteLen == utf8.RuneCountInString(s) {
+		if byteLen <= maxDisplayWidth {
+			return s
+		}
+		return string(rs[:maxDisplayWidth-1]) + "…"
+	}
+
+	var (
+		display      []int
+		displayWidth int
+	)
+	for _, r := range rs {
+		cw := charWidth(r)
+		displayWidth += cw
+		display = append(display, displayWidth)
+	}
+	if displayWidth <= maxDisplayWidth {
+		return s
+	}
+	for i := range display {
+		if display[i] <= maxDisplayWidth-1 && display[i+1] > maxDisplayWidth-1 {
+			return string(rs[:i+1]) + "…"
+		}
+	}
+	return s
+}

cli/command/formatter/displayutils_test.go

@@ -0,0 +1,30 @@
+package formatter
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestEllipsis(t *testing.T) {
+	var testcases = []struct {
+		source   string
+		width    int
+		expected string
+	}{
+		{source: "t🐳ststring", width: 0, expected: ""},
+		{source: "t🐳ststring", width: 1, expected: "t"},
+		{source: "t🐳ststring", width: 2, expected: "t…"},
+		{source: "t🐳ststring", width: 6, expected: "t🐳st…"},
+		{source: "t🐳ststring", width: 20, expected: "t🐳ststring"},
+		{source: "你好世界teststring", width: 0, expected: ""},
+		{source: "你好世界teststring", width: 1, expected: "你"},
+		{source: "你好世界teststring", width: 3, expected: "你…"},
+		{source: "你好世界teststring", width: 6, expected: "你好…"},
+		{source: "你好世界teststring", width: 20, expected: "你好世界teststring"},
+	}
+
+	for _, testcase := range testcases {
+		assert.Equal(t, testcase.expected, Ellipsis(testcase.source, testcase.width))
+	}
+}

cli/command/formatter/history.go

@@ -7,7 +7,6 @@ import (
 
 	"github.com/docker/docker/api/types/image"
 	"github.com/docker/docker/pkg/stringid"
-	"github.com/docker/docker/pkg/stringutils"
 	units "github.com/docker/go-units"
 )
 
@@ -93,7 +92,7 @@ func (c *historyContext) CreatedSince() string {
 func (c *historyContext) CreatedBy() string {
 	createdBy := strings.Replace(c.h.CreatedBy, "\t", " ", -1)
 	if c.trunc {
-		return stringutils.Ellipsis(createdBy, 45)
+		return Ellipsis(createdBy, 45)
 	}
 	return createdBy
 }

cli/command/formatter/history_test.go

@@ -10,7 +10,6 @@ import (
 
 	"github.com/docker/docker/api/types/image"
 	"github.com/docker/docker/pkg/stringid"
-	"github.com/docker/docker/pkg/stringutils"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -96,7 +95,7 @@ func TestHistoryContext_CreatedBy(t *testing.T) {
 			historyContext{
 				h:     image.HistoryResponseItem{CreatedBy: withTabs},
 				trunc: true,
-			}, stringutils.Ellipsis(expected, 45), ctx.CreatedBy,
+			}, Ellipsis(expected, 45), ctx.CreatedBy,
 		},
 	}
 
@@ -191,7 +190,7 @@ imageID3            24 hours ago        /bin/bash ls
 imageID4            24 hours ago        /bin/bash grep                                                                                                                 183MB               Hi
 `
 	expectedTrunc := `IMAGE               CREATED             CREATED BY                                      SIZE                COMMENT
-imageID1            24 hours ago        /bin/bash ls && npm i && npm run test && k...   183MB               Hi
+imageID1            24 hours ago        /bin/bash ls && npm i && npm run test && kar…   183MB               Hi
 imageID2            24 hours ago        /bin/bash echo                                  183MB               Hi
 imageID3            24 hours ago        /bin/bash ls                                    183MB               Hi
 imageID4            24 hours ago        /bin/bash grep                                  183MB               Hi

cli/command/formatter/plugin.go

@@ -5,7 +5,6 @@ import (
 
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/pkg/stringid"
-	"github.com/docker/docker/pkg/stringutils"
 )
 
 const (
@@ -80,7 +79,7 @@ func (c *pluginContext) Description() string {
 	desc := strings.Replace(c.p.Config.Description, "\n", "", -1)
 	desc = strings.Replace(desc, "\r", "", -1)
 	if c.trunc {
-		desc = stringutils.Ellipsis(desc, 45)
+		desc = Ellipsis(desc, 45)
 	}
 
 	return desc

cli/command/formatter/search.go

@@ -5,7 +5,6 @@ import (
 	"strings"
 
 	registry "github.com/docker/docker/api/types/registry"
-	"github.com/docker/docker/pkg/stringutils"
 )
 
 const (
@@ -73,7 +72,7 @@ func (c *searchContext) Description() string {
 	desc := strings.Replace(c.s.Description, "\n", " ", -1)
 	desc = strings.Replace(desc, "\r", " ", -1)
 	if c.trunc {
-		desc = stringutils.Ellipsis(desc, 45)
+		desc = Ellipsis(desc, 45)
 	}
 	return desc
 }

cli/command/formatter/search_test.go

@@ -7,7 +7,6 @@ import (
 	"testing"
 
 	registrytypes "github.com/docker/docker/api/types/registry"
-	"github.com/docker/docker/pkg/stringutils"
 	"github.com/gotestyourself/gotestyourself/golden"
 	"github.com/stretchr/testify/assert"
 )
@@ -79,7 +78,7 @@ func TestSearchContextDescription(t *testing.T) {
 		{searchContext{
 			s:     registrytypes.SearchResult{Description: longDescription},
 			trunc: true,
-		}, stringutils.Ellipsis(longDescription, 45), ctx.Description},
+		}, Ellipsis(longDescription, 45), ctx.Description},
 		{searchContext{
 			s:     registrytypes.SearchResult{Description: descriptionWReturns},
 			trunc: false,
@@ -87,7 +86,7 @@ func TestSearchContextDescription(t *testing.T) {
 		{searchContext{
 			s:     registrytypes.SearchResult{Description: descriptionWReturns},
 			trunc: true,
-		}, stringutils.Ellipsis(longDescription, 45), ctx.Description},
+		}, Ellipsis(longDescription, 45), ctx.Description},
 	}
 
 	for _, c := range cases {

vendor.conf

@@ -48,7 +48,7 @@ golang.org/x/crypto 558b6879de74bc843225cde5686419267ff707ca
 golang.org/x/net 7dcfb8076726a3fdd9353b6b8a1f1b6be6811bd6
 golang.org/x/sync 450f422ab23cf9881c94e2db30cac0eb1b7cf80c
 golang.org/x/sys 07c182904dbd53199946ba614a412c61d3c548f5
-golang.org/x/text f72d8390a633d5dfb0cc84043294db9f6c935756
+golang.org/x/text 825fc78a2fd6fa0a5447e300189e3219e05e1f25
 golang.org/x/time a4bde12657593d5e90d0533a3e4fd95e635124cb
 google.golang.org/genproto d80a6e20e776b0b17a324d0ba1ab50a39c8e8944
 google.golang.org/grpc v1.3.0

vendor/github.com/docker/docker/pkg/stringutils/README.md

@@ -1 +0,0 @@
-This package provides helper functions for dealing with strings

vendor/github.com/docker/docker/pkg/stringutils/stringutils.go

@@ -1,99 +0,0 @@
-// Package stringutils provides helper functions for dealing with strings.
-package stringutils
-
-import (
-	"bytes"
-	"math/rand"
-	"strings"
-)
-
-// GenerateRandomAlphaOnlyString generates an alphabetical random string with length n.
-func GenerateRandomAlphaOnlyString(n int) string {
-	// make a really long string
-	letters := []byte("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
-	b := make([]byte, n)
-	for i := range b {
-		b[i] = letters[rand.Intn(len(letters))]
-	}
-	return string(b)
-}
-
-// GenerateRandomASCIIString generates an ASCII random string with length n.
-func GenerateRandomASCIIString(n int) string {
-	chars := "abcdefghijklmnopqrstuvwxyz" +
-		"ABCDEFGHIJKLMNOPQRSTUVWXYZ" +
-		"~!@#$%^&*()-_+={}[]\\|<,>.?/\"';:` "
-	res := make([]byte, n)
-	for i := 0; i < n; i++ {
-		res[i] = chars[rand.Intn(len(chars))]
-	}
-	return string(res)
-}
-
-// Ellipsis truncates a string to fit within maxlen, and appends ellipsis (...).
-// For maxlen of 3 and lower, no ellipsis is appended.
-func Ellipsis(s string, maxlen int) string {
-	r := []rune(s)
-	if len(r) <= maxlen {
-		return s
-	}
-	if maxlen <= 3 {
-		return string(r[:maxlen])
-	}
-	return string(r[:maxlen-3]) + "..."
-}
-
-// Truncate truncates a string to maxlen.
-func Truncate(s string, maxlen int) string {
-	r := []rune(s)
-	if len(r) <= maxlen {
-		return s
-	}
-	return string(r[:maxlen])
-}
-
-// InSlice tests whether a string is contained in a slice of strings or not.
-// Comparison is case insensitive
-func InSlice(slice []string, s string) bool {
-	for _, ss := range slice {
-		if strings.ToLower(s) == strings.ToLower(ss) {
-			return true
-		}
-	}
-	return false
-}
-
-func quote(word string, buf *bytes.Buffer) {
-	// Bail out early for "simple" strings
-	if word != "" && !strings.ContainsAny(word, "\\'\"`${[|&;<>()~*?! \t\n") {
-		buf.WriteString(word)
-		return
-	}
-
-	buf.WriteString("'")
-
-	for i := 0; i < len(word); i++ {
-		b := word[i]
-		if b == '\'' {
-			// Replace literal ' with a close ', a \', and an open '
-			buf.WriteString("'\\''")
-		} else {
-			buf.WriteByte(b)
-		}
-	}
-
-	buf.WriteString("'")
-}
-
-// ShellQuoteArguments takes a list of strings and escapes them so they will be
-// handled right when passed as arguments to a program via a shell
-func ShellQuoteArguments(args []string) string {
-	var buf bytes.Buffer
-	for i, arg := range args {
-		if i != 0 {
-			buf.WriteByte(' ')
-		}
-		quote(arg, &buf)
-	}
-	return buf.String()
-}

vendor/golang.org/x/text/README

@@ -1,23 +0,0 @@
-This repository holds supplementary Go libraries for text processing, many involving Unicode.
-
-To submit changes to this repository, see http://golang.org/doc/contribute.html.
-
-To generate the tables in this repository (except for the encoding tables),
-run go generate from this directory. By default tables are generated for the
-Unicode version in core and the CLDR version defined in
-golang.org/x/text/unicode/cldr.
-
-Running go generate will as a side effect create a DATA subdirectory in this
-directory which holds all files that are used as a source for generating the
-tables. This directory will also serve as a cache.
-
-Run
-
-	go test ./...
-
-from this directory to run all tests. Add the "-tags icu" flag to also run
-ICU conformance tests (if available). This requires that you have the correct
-ICU version installed on your system.
-
-TODO:
-- updating unversioned source files.

vendor/golang.org/x/text/README.md

@@ -0,0 +1,91 @@
+# Go Text
+
+This repository holds supplementary Go libraries for text processing, many involving Unicode.
+
+## Semantic Versioning
+This repo uses Semantic versioning (http://semver.org/), so
+1. MAJOR version when you make incompatible API changes,
+1. MINOR version when you add functionality in a backwards-compatible manner,
+   and
+1. PATCH version when you make backwards-compatible bug fixes.
+
+A Unicode major and minor version bump is mapped to a major version bump in
+x/text.
+A path version bump in Unicode is mapped to a minor version bump in x/text.
+Note that, consistent with the definitions in semver, until version 1.0.0 of
+x/text is reached, the minor version is considered a major version.
+So going from 0.1.0 to 0.2.0 is considered to be a major version bump.
+
+A major new CLDR version is mapped to a minor version increase in x/text.
+Any other new CLDR version is mapped to a patch version increase in x/text.
+
+## Download/Install
+
+The easiest way to install is to run `go get -u golang.org/x/text`. You can
+also manually git clone the repository to `$GOPATH/src/golang.org/x/text`.
+
+## Contribute
+To submit changes to this repository, see http://golang.org/doc/contribute.html.
+
+To generate the tables in this repository (except for the encoding tables),
+run go generate from this directory. By default tables are generated for the
+Unicode version in core and the CLDR version defined in
+golang.org/x/text/unicode/cldr.
+
+Running go generate will as a side effect create a DATA subdirectory in this
+directory, which holds all files that are used as a source for generating the
+tables. This directory will also serve as a cache.
+
+## Testing
+Run
+
+    go test ./...
+
+from this directory to run all tests. Add the "-tags icu" flag to also run
+ICU conformance tests (if available). This requires that you have the correct
+ICU version installed on your system.
+
+TODO:
+- updating unversioned source files.
+
+## Generating Tables
+
+To generate the tables in this repository (except for the encoding
+tables), run `go generate` from this directory. By default tables are
+generated for the Unicode version in core and the CLDR version defined in
+golang.org/x/text/unicode/cldr.
+
+Running go generate will as a side effect create a DATA subdirectory in this
+directory which holds all files that are used as a source for generating the
+tables. This directory will also serve as a cache.
+
+## Versions
+To update a Unicode version run
+
+    UNICODE_VERSION=x.x.x go generate
+
+where `x.x.x` must correspond to a directory in http://www.unicode.org/Public/.
+If this version is newer than the version in core it will also update the
+relevant packages there. The idna package in x/net will always be updated.
+
+To update a CLDR version run
+
+    CLDR_VERSION=version go generate
+
+where `version` must correspond to a directory in
+http://www.unicode.org/Public/cldr/.
+
+Note that the code gets adapted over time to changes in the data and that
+backwards compatibility is not maintained.
+So updating to a different version may not work.
+
+The files in DATA/{iana|icu|w3|whatwg} are currently not versioned.
+
+## Report Issues / Send Patches
+
+This repository uses Gerrit for code changes. To learn how to submit changes to
+this repository, see https://golang.org/doc/contribute.html.
+
+The main issue tracker for the image repository is located at
+https://github.com/golang/go/issues. Prefix your issue with "x/image:" in the
+subject line, so it is easy to find.

vendor/golang.org/x/text/secure/bidirule/bidirule.go

@@ -155,6 +155,7 @@ func DirectionString(s string) bidi.Direction {
 		e, sz := bidi.LookupString(s[i:])
 		if sz == 0 {
 			i++
+			continue
 		}
 		c := e.Class()
 		if c == bidi.R || c == bidi.AL || c == bidi.AN {
@@ -203,9 +204,6 @@ func (t *Transformer) isRTL() bool {
 }
 
 func (t *Transformer) isFinal() bool {
-	if !t.isRTL() {
-		return true
-	}
 	return t.state == ruleLTRFinal || t.state == ruleRTLFinal || t.state == ruleInitial
 }
 

vendor/golang.org/x/text/unicode/bidi/core.go

@@ -726,7 +726,7 @@ loop:
 				continue loop
 			}
 		}
-		log.Panicf("invalid bidi code %s present in assertOnly at position %d", t, s.indexes[i])
+		log.Panicf("invalid bidi code %v present in assertOnly at position %d", t, s.indexes[i])
 	}
 }
 

vendor/golang.org/x/text/unicode/bidi/trieval.go

@@ -1,4 +1,4 @@
-// This file was generated by go generate; DO NOT EDIT
+// Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
 
 package bidi
 

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 inserts the first rune of a segment. It is a faster version of next if
-// first on it.
+// it is known p represents the first rune in a segment.
-func mkStreamSafe(p Properties) streamSafe {
-	return streamSafe(p.nTrailingNonStarters())
-}
-
-// first inserts the first rune of 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
+var formTable = []*formInfo{{
-
+	form:          NFC,
-func init() {
+	composing:     true,
-	formTable = make([]*formInfo, 4)
+	compatibility: false,
-
+	info:          lookupInfoNFC,
-	for i := range formTable {
+	nextMain:      nextComposed,
-		f := &formInfo{}
+}, {
-		formTable[i] = f
+	form:          NFD,
-		f.form = Form(i)
+	composing:     false,
-		if Form(i) == NFKD || Form(i) == NFKC {
+	compatibility: false,
-			f.compatibility = true
+	info:          lookupInfoNFC,
-			f.info = lookupInfoNFKC
+	nextMain:      nextDecomposed,
-		} else {
+}, {
-			f.info = lookupInfoNFC
+	form:          NFKC,
-		}
+	composing:     true,
-		f.nextMain = nextDecomposed
+	compatibility: true,
-		if Form(i) == NFC || Form(i) == NFKC {
+	info:          lookupInfoNFKC,
-			f.nextMain = nextComposed
+	nextMain:      nextComposed,
-			f.composing = true
+}, {
-		}
+	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/normalize.go

@@ -2,8 +2,9 @@
 // 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"
@@ -323,7 +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
@@ -440,6 +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
 		}
@@ -504,16 +506,15 @@ 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 {
+		// TODO: this could be removed if we don't support merging.
+		if rb.nrune > 0 {
 			goto end
+		}
 	} else if s == ssOverflow {
 		rb.insertCGJ()
 		goto end
 	}
-	} else {
-		rb.ss.first(info)
-	}
 	if err := rb.insertFlush(rb.src, sp, info); err != iSuccess {
 		return int(err)
 	}

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

@@ -40,7 +40,7 @@ func (f Form) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error)
 }
 
 func flushTransform(rb *reorderBuffer) bool {
-	// Write out (must fully fit in dst, or else it is a ErrShortDst).
+	// Write out (must fully fit in dst, or else it is an ErrShortDst).
 	if len(rb.out) < rb.nrune*utf8.UTFMax {
 		return false
 	}

vendor/golang.org/x/text/width/kind_string.go

@@ -0,0 +1,16 @@
+// Code generated by "stringer -type=Kind"; DO NOT EDIT.
+
+package width
+
+import "fmt"
+
+const _Kind_name = "NeutralEastAsianAmbiguousEastAsianWideEastAsianNarrowEastAsianFullwidthEastAsianHalfwidth"
+
+var _Kind_index = [...]uint8{0, 7, 25, 38, 53, 71, 89}
+
+func (i Kind) String() string {
+	if i < 0 || i >= Kind(len(_Kind_index)-1) {
+		return fmt.Sprintf("Kind(%d)", i)
+	}
+	return _Kind_name[_Kind_index[i]:_Kind_index[i+1]]
+}

vendor/golang.org/x/text/width/transform.go

@@ -0,0 +1,239 @@
+// Copyright 2015 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 width
+
+import (
+	"unicode/utf8"
+
+	"golang.org/x/text/transform"
+)
+
+type foldTransform struct {
+	transform.NopResetter
+}
+
+func (foldTransform) Span(src []byte, atEOF bool) (n int, err error) {
+	for n < len(src) {
+		if src[n] < utf8.RuneSelf {
+			// ASCII fast path.
+			for n++; n < len(src) && src[n] < utf8.RuneSelf; n++ {
+			}
+			continue
+		}
+		v, size := trie.lookup(src[n:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				err = transform.ErrShortSrc
+			} else {
+				n = len(src)
+			}
+			break
+		}
+		if elem(v)&tagNeedsFold != 0 {
+			err = transform.ErrEndOfSpan
+			break
+		}
+		n += size
+	}
+	return n, err
+}
+
+func (foldTransform) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	for nSrc < len(src) {
+		if src[nSrc] < utf8.RuneSelf {
+			// ASCII fast path.
+			start, end := nSrc, len(src)
+			if d := len(dst) - nDst; d < end-start {
+				end = nSrc + d
+			}
+			for nSrc++; nSrc < end && src[nSrc] < utf8.RuneSelf; nSrc++ {
+			}
+			n := copy(dst[nDst:], src[start:nSrc])
+			if nDst += n; nDst == len(dst) {
+				nSrc = start + n
+				if nSrc == len(src) {
+					return nDst, nSrc, nil
+				}
+				if src[nSrc] < utf8.RuneSelf {
+					return nDst, nSrc, transform.ErrShortDst
+				}
+			}
+			continue
+		}
+		v, size := trie.lookup(src[nSrc:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				return nDst, nSrc, transform.ErrShortSrc
+			}
+			size = 1 // gobble 1 byte
+		}
+		if elem(v)&tagNeedsFold == 0 {
+			if size != copy(dst[nDst:], src[nSrc:nSrc+size]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			nDst += size
+		} else {
+			data := inverseData[byte(v)]
+			if len(dst)-nDst < int(data[0]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			i := 1
+			for end := int(data[0]); i < end; i++ {
+				dst[nDst] = data[i]
+				nDst++
+			}
+			dst[nDst] = data[i] ^ src[nSrc+size-1]
+			nDst++
+		}
+		nSrc += size
+	}
+	return nDst, nSrc, nil
+}
+
+type narrowTransform struct {
+	transform.NopResetter
+}
+
+func (narrowTransform) Span(src []byte, atEOF bool) (n int, err error) {
+	for n < len(src) {
+		if src[n] < utf8.RuneSelf {
+			// ASCII fast path.
+			for n++; n < len(src) && src[n] < utf8.RuneSelf; n++ {
+			}
+			continue
+		}
+		v, size := trie.lookup(src[n:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				err = transform.ErrShortSrc
+			} else {
+				n = len(src)
+			}
+			break
+		}
+		if k := elem(v).kind(); byte(v) == 0 || k != EastAsianFullwidth && k != EastAsianWide && k != EastAsianAmbiguous {
+		} else {
+			err = transform.ErrEndOfSpan
+			break
+		}
+		n += size
+	}
+	return n, err
+}
+
+func (narrowTransform) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	for nSrc < len(src) {
+		if src[nSrc] < utf8.RuneSelf {
+			// ASCII fast path.
+			start, end := nSrc, len(src)
+			if d := len(dst) - nDst; d < end-start {
+				end = nSrc + d
+			}
+			for nSrc++; nSrc < end && src[nSrc] < utf8.RuneSelf; nSrc++ {
+			}
+			n := copy(dst[nDst:], src[start:nSrc])
+			if nDst += n; nDst == len(dst) {
+				nSrc = start + n
+				if nSrc == len(src) {
+					return nDst, nSrc, nil
+				}
+				if src[nSrc] < utf8.RuneSelf {
+					return nDst, nSrc, transform.ErrShortDst
+				}
+			}
+			continue
+		}
+		v, size := trie.lookup(src[nSrc:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				return nDst, nSrc, transform.ErrShortSrc
+			}
+			size = 1 // gobble 1 byte
+		}
+		if k := elem(v).kind(); byte(v) == 0 || k != EastAsianFullwidth && k != EastAsianWide && k != EastAsianAmbiguous {
+			if size != copy(dst[nDst:], src[nSrc:nSrc+size]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			nDst += size
+		} else {
+			data := inverseData[byte(v)]
+			if len(dst)-nDst < int(data[0]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			i := 1
+			for end := int(data[0]); i < end; i++ {
+				dst[nDst] = data[i]
+				nDst++
+			}
+			dst[nDst] = data[i] ^ src[nSrc+size-1]
+			nDst++
+		}
+		nSrc += size
+	}
+	return nDst, nSrc, nil
+}
+
+type wideTransform struct {
+	transform.NopResetter
+}
+
+func (wideTransform) Span(src []byte, atEOF bool) (n int, err error) {
+	for n < len(src) {
+		// TODO: Consider ASCII fast path. Special-casing ASCII handling can
+		// reduce the ns/op of BenchmarkWideASCII by about 30%. This is probably
+		// not enough to warrant the extra code and complexity.
+		v, size := trie.lookup(src[n:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				err = transform.ErrShortSrc
+			} else {
+				n = len(src)
+			}
+			break
+		}
+		if k := elem(v).kind(); byte(v) == 0 || k != EastAsianHalfwidth && k != EastAsianNarrow {
+		} else {
+			err = transform.ErrEndOfSpan
+			break
+		}
+		n += size
+	}
+	return n, err
+}
+
+func (wideTransform) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	for nSrc < len(src) {
+		// TODO: Consider ASCII fast path. Special-casing ASCII handling can
+		// reduce the ns/op of BenchmarkWideASCII by about 30%. This is probably
+		// not enough to warrant the extra code and complexity.
+		v, size := trie.lookup(src[nSrc:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				return nDst, nSrc, transform.ErrShortSrc
+			}
+			size = 1 // gobble 1 byte
+		}
+		if k := elem(v).kind(); byte(v) == 0 || k != EastAsianHalfwidth && k != EastAsianNarrow {
+			if size != copy(dst[nDst:], src[nSrc:nSrc+size]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			nDst += size
+		} else {
+			data := inverseData[byte(v)]
+			if len(dst)-nDst < int(data[0]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			i := 1
+			for end := int(data[0]); i < end; i++ {
+				dst[nDst] = data[i]
+				nDst++
+			}
+			dst[nDst] = data[i] ^ src[nSrc+size-1]
+			nDst++
+		}
+		nSrc += size
+	}
+	return nDst, nSrc, nil
+}

vendor/golang.org/x/text/width/trieval.go

@@ -0,0 +1,30 @@
+// Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
+
+package width
+
+// elem is an entry of the width trie. The high byte is used to encode the type
+// of the rune. The low byte is used to store the index to a mapping entry in
+// the inverseData array.
+type elem uint16
+
+const (
+	tagNeutral elem = iota << typeShift
+	tagAmbiguous
+	tagWide
+	tagNarrow
+	tagFullwidth
+	tagHalfwidth
+)
+
+const (
+	numTypeBits = 3
+	typeShift   = 16 - numTypeBits
+
+	// tagNeedsFold is true for all fullwidth and halfwidth runes except for
+	// the Won sign U+20A9.
+	tagNeedsFold = 0x1000
+
+	// The Korean Won sign is halfwidth, but SHOULD NOT be mapped to a wide
+	// variant.
+	wonSign rune = 0x20A9
+)

vendor/golang.org/x/text/width/width.go

@@ -0,0 +1,206 @@
+// Copyright 2015 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.
+
+//go:generate stringer -type=Kind
+//go:generate go run gen.go gen_common.go gen_trieval.go
+
+// Package width provides functionality for handling different widths in text.
+//
+// Wide characters behave like ideographs; they tend to allow line breaks after
+// each character and remain upright in vertical text layout. Narrow characters
+// are kept together in words or runs that are rotated sideways in vertical text
+// layout.
+//
+// For more information, see http://unicode.org/reports/tr11/.
+package width // import "golang.org/x/text/width"
+
+import (
+	"unicode/utf8"
+
+	"golang.org/x/text/transform"
+)
+
+// TODO
+// 1) Reduce table size by compressing blocks.
+// 2) API proposition for computing display length
+//    (approximation, fixed pitch only).
+// 3) Implement display length.
+
+// Kind indicates the type of width property as defined in http://unicode.org/reports/tr11/.
+type Kind int
+
+const (
+	// Neutral characters do not occur in legacy East Asian character sets.
+	Neutral Kind = iota
+
+	// EastAsianAmbiguous characters that can be sometimes wide and sometimes
+	// narrow and require additional information not contained in the character
+	// code to further resolve their width.
+	EastAsianAmbiguous
+
+	// EastAsianWide characters are wide in its usual form. They occur only in
+	// the context of East Asian typography. These runes may have explicit
+	// halfwidth counterparts.
+	EastAsianWide
+
+	// EastAsianNarrow characters are narrow in its usual form. They often have
+	// fullwidth counterparts.
+	EastAsianNarrow
+
+	// Note: there exist Narrow runes that do not have fullwidth or wide
+	// counterparts, despite what the definition says (e.g. U+27E6).
+
+	// EastAsianFullwidth characters have a compatibility decompositions of type
+	// wide that map to a narrow counterpart.
+	EastAsianFullwidth
+
+	// EastAsianHalfwidth characters have a compatibility decomposition of type
+	// narrow that map to a wide or ambiguous counterpart, plus U+20A9 ₩ WON
+	// SIGN.
+	EastAsianHalfwidth
+
+	// Note: there exist runes that have a halfwidth counterparts but that are
+	// classified as Ambiguous, rather than wide (e.g. U+2190).
+)
+
+// TODO: the generated tries need to return size 1 for invalid runes for the
+// width to be computed correctly (each byte should render width 1)
+
+var trie = newWidthTrie(0)
+
+// Lookup reports the Properties of the first rune in b and the number of bytes
+// of its UTF-8 encoding.
+func Lookup(b []byte) (p Properties, size int) {
+	v, sz := trie.lookup(b)
+	return Properties{elem(v), b[sz-1]}, sz
+}
+
+// LookupString reports the Properties of the first rune in s and the number of
+// bytes of its UTF-8 encoding.
+func LookupString(s string) (p Properties, size int) {
+	v, sz := trie.lookupString(s)
+	return Properties{elem(v), s[sz-1]}, sz
+}
+
+// LookupRune reports the Properties of rune r.
+func LookupRune(r rune) Properties {
+	var buf [4]byte
+	n := utf8.EncodeRune(buf[:], r)
+	v, _ := trie.lookup(buf[:n])
+	last := byte(r)
+	if r >= utf8.RuneSelf {
+		last = 0x80 + byte(r&0x3f)
+	}
+	return Properties{elem(v), last}
+}
+
+// Properties provides access to width properties of a rune.
+type Properties struct {
+	elem elem
+	last byte
+}
+
+func (e elem) kind() Kind {
+	return Kind(e >> typeShift)
+}
+
+// Kind returns the Kind of a rune as defined in Unicode TR #11.
+// See http://unicode.org/reports/tr11/ for more details.
+func (p Properties) Kind() Kind {
+	return p.elem.kind()
+}
+
+// Folded returns the folded variant of a rune or 0 if the rune is canonical.
+func (p Properties) Folded() rune {
+	if p.elem&tagNeedsFold != 0 {
+		buf := inverseData[byte(p.elem)]
+		buf[buf[0]] ^= p.last
+		r, _ := utf8.DecodeRune(buf[1 : 1+buf[0]])
+		return r
+	}
+	return 0
+}
+
+// Narrow returns the narrow variant of a rune or 0 if the rune is already
+// narrow or doesn't have a narrow variant.
+func (p Properties) Narrow() rune {
+	if k := p.elem.kind(); byte(p.elem) != 0 && (k == EastAsianFullwidth || k == EastAsianWide || k == EastAsianAmbiguous) {
+		buf := inverseData[byte(p.elem)]
+		buf[buf[0]] ^= p.last
+		r, _ := utf8.DecodeRune(buf[1 : 1+buf[0]])
+		return r
+	}
+	return 0
+}
+
+// Wide returns the wide variant of a rune or 0 if the rune is already
+// wide or doesn't have a wide variant.
+func (p Properties) Wide() rune {
+	if k := p.elem.kind(); byte(p.elem) != 0 && (k == EastAsianHalfwidth || k == EastAsianNarrow) {
+		buf := inverseData[byte(p.elem)]
+		buf[buf[0]] ^= p.last
+		r, _ := utf8.DecodeRune(buf[1 : 1+buf[0]])
+		return r
+	}
+	return 0
+}
+
+// TODO for Properties:
+// - Add Fullwidth/Halfwidth or Inverted methods for computing variants
+// mapping.
+// - Add width information (including information on non-spacing runes).
+
+// Transformer implements the transform.Transformer interface.
+type Transformer struct {
+	t transform.SpanningTransformer
+}
+
+// Reset implements the transform.Transformer interface.
+func (t Transformer) Reset() { t.t.Reset() }
+
+// Transform implements the transform.Transformer interface.
+func (t Transformer) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	return t.t.Transform(dst, src, atEOF)
+}
+
+// Span implements the transform.SpanningTransformer interface.
+func (t Transformer) Span(src []byte, atEOF bool) (n int, err error) {
+	return t.t.Span(src, atEOF)
+}
+
+// Bytes returns a new byte slice with the result of applying t to b.
+func (t Transformer) Bytes(b []byte) []byte {
+	b, _, _ = transform.Bytes(t, b)
+	return b
+}
+
+// String returns a string with the result of applying t to s.
+func (t Transformer) String(s string) string {
+	s, _, _ = transform.String(t, s)
+	return s
+}
+
+var (
+	// Fold is a transform that maps all runes to their canonical width.
+	//
+	// Note that the NFKC and NFKD transforms in golang.org/x/text/unicode/norm
+	// provide a more generic folding mechanism.
+	Fold Transformer = Transformer{foldTransform{}}
+
+	// Widen is a transform that maps runes to their wide variant, if
+	// available.
+	Widen Transformer = Transformer{wideTransform{}}
+
+	// Narrow is a transform that maps runes to their narrow variant, if
+	// available.
+	Narrow Transformer = Transformer{narrowTransform{}}
+)
+
+// TODO: Consider the following options:
+// - Treat Ambiguous runes that have a halfwidth counterpart as wide, or some
+//   generalized variant of this.
+// - Consider a wide Won character to be the default width (or some generalized
+//   variant of this).
+// - Filter the set of characters that gets converted (the preferred approach is
+//   to allow applying filters to transforms).