VMware vSphere Integrated Containers provider (#206)

* Add Virtual Kubelet provider for VIC

Initial virtual kubelet provider for VMware VIC.  This provider currently
handles creating and starting of a pod VM via the VIC portlayer and persona
server.  Image store handling via the VIC persona server.  This provider
currently requires the feature/wolfpack branch of VIC.

* Added pod stop and delete.  Also added node capacity.

Added the ability to stop and delete pod VMs via VIC.  Also retrieve
node capacity information from the VCH.

* Cleanup and readme file

Some file clean up and added a Readme.md markdown file for the VIC
provider.

* Cleaned up errors, added function comments, moved operation code

1. Cleaned up error handling.  Set standard for creating errors.
2. Added method prototype comments for all interface functions.
3. Moved PodCreator, PodStarter, PodStopper, and PodDeleter to a new folder.

* Add mocking code and unit tests for podcache, podcreator, and podstarter

Used the unit test framework used in VIC to handle assertions in the provider's
unit test.  Mocking code generated using OSS project mockery, which is compatible
with the testify assertion framework.

* Vendored packages for the VIC provider

Requires feature/wolfpack branch of VIC and a few specific commit sha of
projects used within VIC.

* Implementation of POD Stopper and Deleter unit tests (#4)

* Updated files for initial PR

vendor/github.com/kr/text/License

@@ -0,0 +1,19 @@
+Copyright 2012 Keith Rarick
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

vendor/github.com/kr/text/Readme

@@ -0,0 +1,3 @@
+This is a Go package for manipulating paragraphs of text.
+
+See http://go.pkgdoc.org/github.com/kr/text for full documentation.

vendor/github.com/kr/text/cmd/agg/doc.go

@@ -0,0 +1,73 @@
+/*
+
+Agg computes aggregate values over tabular text.
+It behaves somewhat like the SQL “GROUP BY” clause.
+
+Usage:
+
+	agg [function...]
+
+It reads input from stdin as a sequence of records, one per line.
+It treats each line as a set of fields separated by white space.
+One field (the first, by default) is designated as the key.
+Successive lines with equal keys are grouped into a group,
+and agg produces one line of output for each group.
+(Note that only contiguous input lines can form a group.
+If you need to make sure that all records for a given key
+are grouped together, sort the input first.)
+
+For each remaining field,
+agg applies a function to all the values in the group,
+producing a single output value.
+The command line arguments specify which functions to use,
+one per field in the input table.
+
+Functions
+
+The available functions are:
+
+    key        group by this field (default for field 1)
+    first      value from first line of group (default for rest)
+    last       value from last line of group
+    sample     value from any line of group, uniformly at random
+    prefix     longest common string prefix
+    join:sep   concatenate strings with given sep
+    smin       lexically least string
+    smax       lexically greatest string
+    min        numerically least value
+    max        numerically greatest value
+    sum        numeric sum
+    mean       arithmetic mean
+    count      number of records (ignores input value)
+    const:val  print val, ignoring input
+    drop       omit the column entirely
+
+The numeric functions skip items that don't parse as numbers.
+
+Examples
+
+Using the following input:
+
+    $ cat >input
+    -rwx   alice      100   /home/alice/bin/crdt
+    -rw-   alice   210002   /home/alice/thesis.tex
+    -rw-   bob      10051   /home/bob/expenses.tab
+    -rwx   kr      862060   /home/kr/bin/blog
+    -rwx   kr      304608   /home/kr/bin/agg
+
+Disk usage for each user, plus where that disk usage occurs
+(longest common prefix of filesystem paths):
+
+    $ agg <input drop key sum prefix
+    alice	210153	/home/alice/
+    bob	10051	/home/bob/expenses.tab
+    kr	1166668	/home/kr/
+
+Disk usage for executable vs non-executable files:
+
+    $ sort input | agg key drop sum join:,
+    -rw-	220053	/home/alice/thesis.tex,/home/bob/expenses.tab
+    -rwx	1166768	/home/alice/bin/crdt,/home/kr/bin/agg,/home/kr/bin/blog
+
+*/
+package main

vendor/github.com/kr/text/cmd/agg/main.go

@@ -0,0 +1,112 @@
+package main
+
+// TODO(kr): tests
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"math/rand"
+	"os"
+	"strings"
+	"time"
+)
+
+type agg interface {
+	merge(string)
+	String() string
+}
+
+var (
+	key     = 0
+	funcmap = make(map[int]func(init, arg string) agg)
+	argmap  = make(map[int]string)
+	symtab  = map[string]func(init, arg string) agg{
+		"first":  first,
+		"last":   last,
+		"prefix": prefix,
+		"sample": sample,
+		"join":   join,
+		"smin":   smin,
+		"smax":   smax,
+		"min":    min,
+		"max":    max,
+		"sum":    sum,
+		"mean":   mean,
+		"count":  count,
+		"const":  constf,
+		"drop":   nil,
+	}
+)
+
+func main() {
+	log.SetPrefix("agg: ")
+	log.SetFlags(0)
+	rand.Seed(time.Now().UnixNano())
+	for i, sym := range os.Args[1:] {
+		if p := strings.IndexByte(sym, ':'); p >= 0 {
+			sym, argmap[i] = sym[:p], sym[p+1:]
+		}
+		if sym == "key" {
+			key, sym = i, "first"
+		}
+		f, ok := symtab[sym]
+		if !ok {
+			log.Fatalf("bad function: %q", sym)
+		}
+		funcmap[i] = f
+	}
+
+	sc := bufio.NewScanner(os.Stdin)
+	var g *group
+	for sc.Scan() {
+		ss := strings.Fields(sc.Text())
+		if !matches(g, ss) {
+			emit(g)
+			g = &group{key: ss[key]}
+		}
+		mergeLine(g, ss)
+	}
+	emit(g)
+}
+
+type group struct {
+	key string
+	agg []agg
+}
+
+func matches(g *group, ss []string) bool {
+	return g != nil && g.key == ss[key]
+}
+
+func emit(g *group) {
+	if g == nil {
+		return
+	}
+	rest := false
+	for i, a := range g.agg {
+		if f, ok := funcmap[i]; ok && f == nil {
+			continue
+		}
+		if rest {
+			fmt.Print("\t")
+		}
+		rest = true
+		fmt.Print(a)
+	}
+	fmt.Println()
+}
+
+func mergeLine(g *group, ss []string) {
+	for i, s := range ss {
+		if i >= len(g.agg) {
+			f := funcmap[i]
+			if f == nil {
+				f = first
+			}
+			g.agg = append(g.agg, f(s, argmap[i]))
+		} else {
+			g.agg[i].merge(s)
+		}
+	}
+}

vendor/github.com/kr/text/cmd/agg/num.go

@@ -0,0 +1,99 @@
+package main
+
+import (
+	"math/big"
+	"strconv"
+)
+
+func min(s, arg string) agg { return newBinop(s, opmin) }
+func max(s, arg string) agg { return newBinop(s, opmax) }
+func sum(s, arg string) agg { return newBinop(s, opsum) }
+
+type binop struct {
+	v *big.Float
+	f func(a, b *big.Float) *big.Float
+}
+
+func newBinop(s string, f func(a, b *big.Float) *big.Float) *binop {
+	v, _ := parseFloat(s)
+	return &binop{v, f}
+}
+
+func (o *binop) String() string {
+	if o.v == nil {
+		return "NaN"
+	}
+	return o.v.Text('f', -1)
+}
+
+func (o *binop) merge(s string) {
+	v, ok := parseFloat(s)
+	if !ok {
+		return
+	}
+	o.v = o.f(o.v, v)
+}
+
+func opmin(a, b *big.Float) *big.Float {
+	if a != nil && (b == nil || a.Cmp(b) <= 0) {
+		return a
+	}
+	return b
+}
+
+func opmax(a, b *big.Float) *big.Float {
+	if a != nil && (b == nil || a.Cmp(b) >= 0) {
+		return a
+	}
+	return b
+}
+
+func opsum(a, b *big.Float) *big.Float {
+	if a == nil {
+		return b
+	} else if b == nil {
+		return a
+	}
+	return a.Add(a, b)
+}
+
+type meanagg struct {
+	v *big.Float
+	d float64 // actually an integer
+}
+
+func mean(s, arg string) agg {
+	v, ok := parseFloat(s)
+	if !ok {
+		return &meanagg{new(big.Float), 0}
+	}
+	return &meanagg{v, 1}
+}
+
+func (m *meanagg) String() string {
+	if m.d == 0 {
+		return "NaN"
+	}
+	v := new(big.Float).Quo(m.v, big.NewFloat(m.d))
+	return v.Text('f', -1)
+}
+
+func (m *meanagg) merge(s string) {
+	v, ok := parseFloat(s)
+	if !ok {
+		return
+	}
+	m.v.Add(m.v, v)
+	m.d++
+}
+
+func parseFloat(s string) (*big.Float, bool) {
+	v, _, err := big.ParseFloat(s, 0, 1000, big.ToNearestEven)
+	return v, err == nil
+}
+
+type counter int
+
+func count(init, arg string) agg  { return new(counter) }
+func (c *counter) String() string { return strconv.Itoa(int(*c) + 1) }
+func (c *counter) merge(string)   { *c++ }

vendor/github.com/kr/text/cmd/agg/string.go

@@ -0,0 +1,74 @@
+package main
+
+import (
+	"math/rand"
+	"strings"
+)
+
+func first(s, arg string) agg  { return &sbinop{s, opfirst} }
+func last(s, arg string) agg   { return &sbinop{s, oplast} }
+func prefix(s, arg string) agg { return &sbinop{s, opprefix} }
+func join(s, arg string) agg   { return &sbinop{s, opjoin(arg)} }
+func smin(s, arg string) agg   { return &sbinop{s, opsmin} }
+func smax(s, arg string) agg   { return &sbinop{s, opsmax} }
+
+type sbinop struct {
+	s string
+	f func(a, b string) string
+}
+
+func (o *sbinop) String() string { return o.s }
+
+func (o *sbinop) merge(s string) { o.s = o.f(o.s, s) }
+
+func opfirst(a, b string) string { return a }
+func oplast(a, b string) string  { return b }
+
+func opprefix(a, b string) string {
+	for i := range a {
+		if i >= len(b) || a[i] != b[i] {
+			return a[:i]
+		}
+	}
+	return a
+}
+
+func opjoin(sep string) func(a, b string) string {
+	return func(a, b string) string {
+		return a + sep + b // TODO(kr): too slow? maybe strings.Join?
+	}
+}
+
+func opsmin(a, b string) string {
+	if strings.Compare(a, b) <= 0 {
+		return a
+	}
+	return b
+}
+
+func opsmax(a, b string) string {
+	if strings.Compare(a, b) >= 0 {
+		return a
+	}
+	return b
+}
+
+type sampler struct {
+	n int
+	s string
+}
+
+func sample(s, arg string) agg    { return &sampler{1, s} }
+func (p *sampler) String() string { return p.s }
+func (p *sampler) merge(s string) {
+	p.n++
+	if rand.Intn(p.n) == 0 {
+		p.s = s
+	}
+}
+
+type constant string
+
+func constf(init, arg string) agg { return constant(arg) }
+func (c constant) String() string { return string(c) }
+func (c constant) merge(string)   {}

vendor/github.com/kr/text/colwriter/Readme

@@ -0,0 +1,5 @@
+Package colwriter provides a write filter that formats
+input lines in multiple columns.
+
+The package is a straightforward translation from
+/src/cmd/draw/mc.c in Plan 9 from User Space.

vendor/github.com/kr/text/colwriter/column.go

@@ -0,0 +1,147 @@
+// Package colwriter provides a write filter that formats
+// input lines in multiple columns.
+//
+// The package is a straightforward translation from
+// /src/cmd/draw/mc.c in Plan 9 from User Space.
+package colwriter
+
+import (
+	"bytes"
+	"io"
+	"unicode/utf8"
+)
+
+const (
+	tab = 4
+)
+
+const (
+	// Print each input line ending in a colon ':' separately.
+	BreakOnColon uint = 1 << iota
+)
+
+// A Writer is a filter that arranges input lines in as many columns as will
+// fit in its width. Tab '\t' chars in the input are translated to sequences
+// of spaces ending at multiples of 4 positions.
+//
+// If BreakOnColon is set, each input line ending in a colon ':' is written
+// separately.
+//
+// The Writer assumes that all Unicode code points have the same width; this
+// may not be true in some fonts.
+type Writer struct {
+	w     io.Writer
+	buf   []byte
+	width int
+	flag  uint
+}
+
+// NewWriter allocates and initializes a new Writer writing to w.
+// Parameter width controls the total number of characters on each line
+// across all columns.
+func NewWriter(w io.Writer, width int, flag uint) *Writer {
+	return &Writer{
+		w:     w,
+		width: width,
+		flag:  flag,
+	}
+}
+
+// Write writes p to the writer w. The only errors returned are ones
+// encountered while writing to the underlying output stream.
+func (w *Writer) Write(p []byte) (n int, err error) {
+	var linelen int
+	var lastWasColon bool
+	for i, c := range p {
+		w.buf = append(w.buf, c)
+		linelen++
+		if c == '\t' {
+			w.buf[len(w.buf)-1] = ' '
+			for linelen%tab != 0 {
+				w.buf = append(w.buf, ' ')
+				linelen++
+			}
+		}
+		if w.flag&BreakOnColon != 0 && c == ':' {
+			lastWasColon = true
+		} else if lastWasColon {
+			if c == '\n' {
+				pos := bytes.LastIndex(w.buf[:len(w.buf)-1], []byte{'\n'})
+				if pos < 0 {
+					pos = 0
+				}
+				line := w.buf[pos:]
+				w.buf = w.buf[:pos]
+				if err = w.columnate(); err != nil {
+					if len(line) < i {
+						return i - len(line), err
+					}
+					return 0, err
+				}
+				if n, err := w.w.Write(line); err != nil {
+					if r := len(line) - n; r < i {
+						return i - r, err
+					}
+					return 0, err
+				}
+			}
+			lastWasColon = false
+		}
+		if c == '\n' {
+			linelen = 0
+		}
+	}
+	return len(p), nil
+}
+
+// Flush should be called after the last call to Write to ensure that any data
+// buffered in the Writer is written to output.
+func (w *Writer) Flush() error {
+	return w.columnate()
+}
+
+func (w *Writer) columnate() error {
+	words := bytes.Split(w.buf, []byte{'\n'})
+	w.buf = nil
+	if len(words[len(words)-1]) == 0 {
+		words = words[:len(words)-1]
+	}
+	maxwidth := 0
+	for _, wd := range words {
+		if n := utf8.RuneCount(wd); n > maxwidth {
+			maxwidth = n
+		}
+	}
+	maxwidth++ // space char
+	wordsPerLine := w.width / maxwidth
+	if wordsPerLine <= 0 {
+		wordsPerLine = 1
+	}
+	nlines := (len(words) + wordsPerLine - 1) / wordsPerLine
+	for i := 0; i < nlines; i++ {
+		col := 0
+		endcol := 0
+		for j := i; j < len(words); j += nlines {
+			endcol += maxwidth
+			_, err := w.w.Write(words[j])
+			if err != nil {
+				return err
+			}
+			col += utf8.RuneCount(words[j])
+			if j+nlines < len(words) {
+				for col < endcol {
+					_, err := w.w.Write([]byte{' '})
+					if err != nil {
+						return err
+					}
+					col++
+				}
+			}
+		}
+		_, err := w.w.Write([]byte{'\n'})
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

vendor/github.com/kr/text/colwriter/column_test.go

@@ -0,0 +1,90 @@
+package colwriter
+
+import (
+	"bytes"
+	"testing"
+)
+
+var src = `
+.git
+.gitignore
+.godir
+Procfile:
+README.md
+api.go
+apps.go
+auth.go
+darwin.go
+data.go
+dyno.go:
+env.go
+git.go
+help.go
+hkdist
+linux.go
+ls.go
+main.go
+plugin.go
+run.go
+scale.go
+ssh.go
+tail.go
+term
+unix.go
+update.go
+version.go
+windows.go
+`[1:]
+
+var tests = []struct {
+	wid  int
+	flag uint
+	src  string
+	want string
+}{
+	{80, 0, "", ""},
+	{80, 0, src, `
+.git       README.md  darwin.go  git.go     ls.go      scale.go   unix.go
+.gitignore api.go     data.go    help.go    main.go    ssh.go     update.go
+.godir     apps.go    dyno.go:   hkdist     plugin.go  tail.go    version.go
+Procfile:  auth.go    env.go     linux.go   run.go     term       windows.go
+`[1:]},
+	{80, BreakOnColon, src, `
+.git       .gitignore .godir
+
+Procfile:
+README.md api.go    apps.go   auth.go   darwin.go data.go
+
+dyno.go:
+env.go     hkdist     main.go    scale.go   term       version.go
+git.go     linux.go   plugin.go  ssh.go     unix.go    windows.go
+help.go    ls.go      run.go     tail.go    update.go
+`[1:]},
+	{20, 0, `
+Hello
+Γειά σου
+안녕
+今日は
+`[1:], `
+Hello    안녕
+Γειά σου 今日は
+`[1:]},
+}
+
+func TestWriter(t *testing.T) {
+	for _, test := range tests {
+		b := new(bytes.Buffer)
+		w := NewWriter(b, test.wid, test.flag)
+		if _, err := w.Write([]byte(test.src)); err != nil {
+			t.Error(err)
+		}
+		if err := w.Flush(); err != nil {
+			t.Error(err)
+		}
+		if g := b.String(); test.want != g {
+			t.Log("\n" + test.want)
+			t.Log("\n" + g)
+			t.Errorf("%q != %q", test.want, g)
+		}
+	}
+}

vendor/github.com/kr/text/doc.go

@@ -0,0 +1,3 @@
+// Package text provides rudimentary functions for manipulating text in
+// paragraphs.
+package text

vendor/github.com/kr/text/indent.go

@@ -0,0 +1,74 @@
+package text
+
+import (
+	"io"
+)
+
+// Indent inserts prefix at the beginning of each non-empty line of s. The
+// end-of-line marker is NL.
+func Indent(s, prefix string) string {
+	return string(IndentBytes([]byte(s), []byte(prefix)))
+}
+
+// IndentBytes inserts prefix at the beginning of each non-empty line of b.
+// The end-of-line marker is NL.
+func IndentBytes(b, prefix []byte) []byte {
+	var res []byte
+	bol := true
+	for _, c := range b {
+		if bol && c != '\n' {
+			res = append(res, prefix...)
+		}
+		res = append(res, c)
+		bol = c == '\n'
+	}
+	return res
+}
+
+// Writer indents each line of its input.
+type indentWriter struct {
+	w   io.Writer
+	bol bool
+	pre [][]byte
+	sel int
+	off int
+}
+
+// NewIndentWriter makes a new write filter that indents the input
+// lines. Each line is prefixed in order with the corresponding
+// element of pre. If there are more lines than elements, the last
+// element of pre is repeated for each subsequent line.
+func NewIndentWriter(w io.Writer, pre ...[]byte) io.Writer {
+	return &indentWriter{
+		w:   w,
+		pre: pre,
+		bol: true,
+	}
+}
+
+// The only errors returned are from the underlying indentWriter.
+func (w *indentWriter) Write(p []byte) (n int, err error) {
+	for _, c := range p {
+		if w.bol {
+			var i int
+			i, err = w.w.Write(w.pre[w.sel][w.off:])
+			w.off += i
+			if err != nil {
+				return n, err
+			}
+		}
+		_, err = w.w.Write([]byte{c})
+		if err != nil {
+			return n, err
+		}
+		n++
+		w.bol = c == '\n'
+		if w.bol {
+			w.off = 0
+			if w.sel < len(w.pre)-1 {
+				w.sel++
+			}
+		}
+	}
+	return n, nil
+}

vendor/github.com/kr/text/indent_test.go

@@ -0,0 +1,119 @@
+package text
+
+import (
+	"bytes"
+	"testing"
+)
+
+type T struct {
+	inp, exp, pre string
+}
+
+var tests = []T{
+	{
+		"The quick brown fox\njumps over the lazy\ndog.\nBut not quickly.\n",
+		"xxxThe quick brown fox\nxxxjumps over the lazy\nxxxdog.\nxxxBut not quickly.\n",
+		"xxx",
+	},
+	{
+		"The quick brown fox\njumps over the lazy\ndog.\n\nBut not quickly.",
+		"xxxThe quick brown fox\nxxxjumps over the lazy\nxxxdog.\n\nxxxBut not quickly.",
+		"xxx",
+	},
+}
+
+func TestIndent(t *testing.T) {
+	for _, test := range tests {
+		got := Indent(test.inp, test.pre)
+		if got != test.exp {
+			t.Errorf("mismatch %q != %q", got, test.exp)
+		}
+	}
+}
+
+type IndentWriterTest struct {
+	inp, exp string
+	pre      []string
+}
+
+var ts = []IndentWriterTest{
+	{
+		`
+The quick brown fox
+jumps over the lazy
+dog.
+But not quickly.
+`[1:],
+		`
+xxxThe quick brown fox
+xxxjumps over the lazy
+xxxdog.
+xxxBut not quickly.
+`[1:],
+		[]string{"xxx"},
+	},
+	{
+		`
+The quick brown fox
+jumps over the lazy
+dog.
+But not quickly.
+`[1:],
+		`
+xxaThe quick brown fox
+xxxjumps over the lazy
+xxxdog.
+xxxBut not quickly.
+`[1:],
+		[]string{"xxa", "xxx"},
+	},
+	{
+		`
+The quick brown fox
+jumps over the lazy
+dog.
+But not quickly.
+`[1:],
+		`
+xxaThe quick brown fox
+xxbjumps over the lazy
+xxcdog.
+xxxBut not quickly.
+`[1:],
+		[]string{"xxa", "xxb", "xxc", "xxx"},
+	},
+	{
+		`
+The quick brown fox
+jumps over the lazy
+dog.
+
+But not quickly.`[1:],
+		`
+xxaThe quick brown fox
+xxxjumps over the lazy
+xxxdog.
+xxx
+xxxBut not quickly.`[1:],
+		[]string{"xxa", "xxx"},
+	},
+}
+
+func TestIndentWriter(t *testing.T) {
+	for _, test := range ts {
+		b := new(bytes.Buffer)
+		pre := make([][]byte, len(test.pre))
+		for i := range test.pre {
+			pre[i] = []byte(test.pre[i])
+		}
+		w := NewIndentWriter(b, pre...)
+		if _, err := w.Write([]byte(test.inp)); err != nil {
+			t.Error(err)
+		}
+		if got := b.String(); got != test.exp {
+			t.Errorf("mismatch %q != %q", got, test.exp)
+			t.Log(got)
+			t.Log(test.exp)
+		}
+	}
+}

vendor/github.com/kr/text/mc/Readme

@@ -0,0 +1,9 @@
+Command mc prints in multiple columns.
+
+  Usage: mc [-] [-N] [file...]
+
+Mc splits the input into as many columns as will fit in N
+print positions. If the output is a tty, the default N is
+the number of characters in a terminal line; otherwise the
+default N is 80. Under option - each input line ending in
+a colon ':' is printed separately.

vendor/github.com/kr/text/mc/mc.go

@@ -0,0 +1,62 @@
+// Command mc prints in multiple columns.
+//
+//   Usage: mc [-] [-N] [file...]
+//
+// Mc splits the input into as many columns as will fit in N
+// print positions. If the output is a tty, the default N is
+// the number of characters in a terminal line; otherwise the
+// default N is 80. Under option - each input line ending in
+// a colon ':' is printed separately.
+package main
+
+import (
+	"github.com/kr/pty"
+	"github.com/kr/text/colwriter"
+	"io"
+	"log"
+	"os"
+	"strconv"
+)
+
+func main() {
+	var width int
+	var flag uint
+	args := os.Args[1:]
+	for len(args) > 0 && len(args[0]) > 0 && args[0][0] == '-' {
+		if len(args[0]) > 1 {
+			width, _ = strconv.Atoi(args[0][1:])
+		} else {
+			flag |= colwriter.BreakOnColon
+		}
+		args = args[1:]
+	}
+	if width < 1 {
+		_, width, _ = pty.Getsize(os.Stdout)
+	}
+	if width < 1 {
+		width = 80
+	}
+
+	w := colwriter.NewWriter(os.Stdout, width, flag)
+	if len(args) > 0 {
+		for _, s := range args {
+			if f, err := os.Open(s); err == nil {
+				copyin(w, f)
+				f.Close()
+			} else {
+				log.Println(err)
+			}
+		}
+	} else {
+		copyin(w, os.Stdin)
+	}
+}
+
+func copyin(w *colwriter.Writer, r io.Reader) {
+	if _, err := io.Copy(w, r); err != nil {
+		log.Println(err)
+	}
+	if err := w.Flush(); err != nil {
+		log.Println(err)
+	}
+}

vendor/github.com/kr/text/wrap.go

@@ -0,0 +1,86 @@
+package text
+
+import (
+	"bytes"
+	"math"
+)
+
+var (
+	nl = []byte{'\n'}
+	sp = []byte{' '}
+)
+
+const defaultPenalty = 1e5
+
+// Wrap wraps s into a paragraph of lines of length lim, with minimal
+// raggedness.
+func Wrap(s string, lim int) string {
+	return string(WrapBytes([]byte(s), lim))
+}
+
+// WrapBytes wraps b into a paragraph of lines of length lim, with minimal
+// raggedness.
+func WrapBytes(b []byte, lim int) []byte {
+	words := bytes.Split(bytes.Replace(bytes.TrimSpace(b), nl, sp, -1), sp)
+	var lines [][]byte
+	for _, line := range WrapWords(words, 1, lim, defaultPenalty) {
+		lines = append(lines, bytes.Join(line, sp))
+	}
+	return bytes.Join(lines, nl)
+}
+
+// WrapWords is the low-level line-breaking algorithm, useful if you need more
+// control over the details of the text wrapping process. For most uses, either
+// Wrap or WrapBytes will be sufficient and more convenient.
+//
+// WrapWords splits a list of words into lines with minimal "raggedness",
+// treating each byte as one unit, accounting for spc units between adjacent
+// words on each line, and attempting to limit lines to lim units. Raggedness
+// is the total error over all lines, where error is the square of the
+// difference of the length of the line and lim. Too-long lines (which only
+// happen when a single word is longer than lim units) have pen penalty units
+// added to the error.
+func WrapWords(words [][]byte, spc, lim, pen int) [][][]byte {
+	n := len(words)
+
+	length := make([][]int, n)
+	for i := 0; i < n; i++ {
+		length[i] = make([]int, n)
+		length[i][i] = len(words[i])
+		for j := i + 1; j < n; j++ {
+			length[i][j] = length[i][j-1] + spc + len(words[j])
+		}
+	}
+
+	nbrk := make([]int, n)
+	cost := make([]int, n)
+	for i := range cost {
+		cost[i] = math.MaxInt32
+	}
+	for i := n - 1; i >= 0; i-- {
+		if length[i][n-1] <= lim || i == n-1 {
+			cost[i] = 0
+			nbrk[i] = n
+		} else {
+			for j := i + 1; j < n; j++ {
+				d := lim - length[i][j-1]
+				c := d*d + cost[j]
+				if length[i][j-1] > lim {
+					c += pen // too-long lines get a worse penalty
+				}
+				if c < cost[i] {
+					cost[i] = c
+					nbrk[i] = j
+				}
+			}
+		}
+	}
+
+	var lines [][][]byte
+	i := 0
+	for i < n {
+		lines = append(lines, words[i:nbrk[i]])
+		i = nbrk[i]
+	}
+	return lines
+}

vendor/github.com/kr/text/wrap_test.go

@@ -0,0 +1,62 @@
+package text
+
+import (
+	"bytes"
+	"testing"
+)
+
+var text = "The quick brown fox jumps over the lazy dog."
+
+func TestWrap(t *testing.T) {
+	exp := [][]string{
+		{"The", "quick", "brown", "fox"},
+		{"jumps", "over", "the", "lazy", "dog."},
+	}
+	words := bytes.Split([]byte(text), sp)
+	got := WrapWords(words, 1, 24, defaultPenalty)
+	if len(exp) != len(got) {
+		t.Fail()
+	}
+	for i := range exp {
+		if len(exp[i]) != len(got[i]) {
+			t.Fail()
+		}
+		for j := range exp[i] {
+			if exp[i][j] != string(got[i][j]) {
+				t.Fatal(i, exp[i][j], got[i][j])
+			}
+		}
+	}
+}
+
+func TestWrapNarrow(t *testing.T) {
+	exp := "The\nquick\nbrown\nfox\njumps\nover\nthe\nlazy\ndog."
+	if Wrap(text, 5) != exp {
+		t.Fail()
+	}
+}
+
+func TestWrapOneLine(t *testing.T) {
+	exp := "The quick brown fox jumps over the lazy dog."
+	if Wrap(text, 500) != exp {
+		t.Fail()
+	}
+}
+
+func TestWrapBug1(t *testing.T) {
+	cases := []struct {
+		limit int
+		text  string
+		want  string
+	}{
+		{4, "aaaaa", "aaaaa"},
+		{4, "a aaaaa", "a\naaaaa"},
+	}
+
+	for _, test := range cases {
+		got := Wrap(test.text, test.limit)
+		if got != test.want {
+			t.Errorf("Wrap(%q, %d) = %q want %q", test.text, test.limit, got, test.want)
+		}
+	}
+}