seba-365 - implemented dep

Change-Id: Ia6226d50e7615935a0c8876809a687427ff88c22
diff --git a/vendor/golang.org/x/text/collate/collate.go b/vendor/golang.org/x/text/collate/collate.go
new file mode 100644
index 0000000..2ce9689
--- /dev/null
+++ b/vendor/golang.org/x/text/collate/collate.go
@@ -0,0 +1,403 @@
+// Copyright 2012 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.
+
+// TODO: remove hard-coded versions when we have implemented fractional weights.
+// The current implementation is incompatible with later CLDR versions.
+//go:generate go run maketables.go -cldr=23 -unicode=6.2.0
+
+// Package collate contains types for comparing and sorting Unicode strings
+// according to a given collation order.
+package collate // import "golang.org/x/text/collate"
+
+import (
+	"bytes"
+	"strings"
+
+	"golang.org/x/text/internal/colltab"
+	"golang.org/x/text/language"
+)
+
+// Collator provides functionality for comparing strings for a given
+// collation order.
+type Collator struct {
+	options
+
+	sorter sorter
+
+	_iter [2]iter
+}
+
+func (c *Collator) iter(i int) *iter {
+	// TODO: evaluate performance for making the second iterator optional.
+	return &c._iter[i]
+}
+
+// Supported returns the list of languages for which collating differs from its parent.
+func Supported() []language.Tag {
+	// TODO: use language.Coverage instead.
+
+	t := make([]language.Tag, len(tags))
+	copy(t, tags)
+	return t
+}
+
+func init() {
+	ids := strings.Split(availableLocales, ",")
+	tags = make([]language.Tag, len(ids))
+	for i, s := range ids {
+		tags[i] = language.Raw.MustParse(s)
+	}
+}
+
+var tags []language.Tag
+
+// New returns a new Collator initialized for the given locale.
+func New(t language.Tag, o ...Option) *Collator {
+	index := colltab.MatchLang(t, tags)
+	c := newCollator(getTable(locales[index]))
+
+	// Set options from the user-supplied tag.
+	c.setFromTag(t)
+
+	// Set the user-supplied options.
+	c.setOptions(o)
+
+	c.init()
+	return c
+}
+
+// NewFromTable returns a new Collator for the given Weighter.
+func NewFromTable(w colltab.Weighter, o ...Option) *Collator {
+	c := newCollator(w)
+	c.setOptions(o)
+	c.init()
+	return c
+}
+
+func (c *Collator) init() {
+	if c.numeric {
+		c.t = colltab.NewNumericWeighter(c.t)
+	}
+	c._iter[0].init(c)
+	c._iter[1].init(c)
+}
+
+// Buffer holds keys generated by Key and KeyString.
+type Buffer struct {
+	buf [4096]byte
+	key []byte
+}
+
+func (b *Buffer) init() {
+	if b.key == nil {
+		b.key = b.buf[:0]
+	}
+}
+
+// Reset clears the buffer from previous results generated by Key and KeyString.
+func (b *Buffer) Reset() {
+	b.key = b.key[:0]
+}
+
+// Compare returns an integer comparing the two byte slices.
+// The result will be 0 if a==b, -1 if a < b, and +1 if a > b.
+func (c *Collator) Compare(a, b []byte) int {
+	// TODO: skip identical prefixes once we have a fast way to detect if a rune is
+	// part of a contraction. This would lead to roughly a 10% speedup for the colcmp regtest.
+	c.iter(0).SetInput(a)
+	c.iter(1).SetInput(b)
+	if res := c.compare(); res != 0 {
+		return res
+	}
+	if !c.ignore[colltab.Identity] {
+		return bytes.Compare(a, b)
+	}
+	return 0
+}
+
+// CompareString returns an integer comparing the two strings.
+// The result will be 0 if a==b, -1 if a < b, and +1 if a > b.
+func (c *Collator) CompareString(a, b string) int {
+	// TODO: skip identical prefixes once we have a fast way to detect if a rune is
+	// part of a contraction. This would lead to roughly a 10% speedup for the colcmp regtest.
+	c.iter(0).SetInputString(a)
+	c.iter(1).SetInputString(b)
+	if res := c.compare(); res != 0 {
+		return res
+	}
+	if !c.ignore[colltab.Identity] {
+		if a < b {
+			return -1
+		} else if a > b {
+			return 1
+		}
+	}
+	return 0
+}
+
+func compareLevel(f func(i *iter) int, a, b *iter) int {
+	a.pce = 0
+	b.pce = 0
+	for {
+		va := f(a)
+		vb := f(b)
+		if va != vb {
+			if va < vb {
+				return -1
+			}
+			return 1
+		} else if va == 0 {
+			break
+		}
+	}
+	return 0
+}
+
+func (c *Collator) compare() int {
+	ia, ib := c.iter(0), c.iter(1)
+	// Process primary level
+	if c.alternate != altShifted {
+		// TODO: implement script reordering
+		if res := compareLevel((*iter).nextPrimary, ia, ib); res != 0 {
+			return res
+		}
+	} else {
+		// TODO: handle shifted
+	}
+	if !c.ignore[colltab.Secondary] {
+		f := (*iter).nextSecondary
+		if c.backwards {
+			f = (*iter).prevSecondary
+		}
+		if res := compareLevel(f, ia, ib); res != 0 {
+			return res
+		}
+	}
+	// TODO: special case handling (Danish?)
+	if !c.ignore[colltab.Tertiary] || c.caseLevel {
+		if res := compareLevel((*iter).nextTertiary, ia, ib); res != 0 {
+			return res
+		}
+		if !c.ignore[colltab.Quaternary] {
+			if res := compareLevel((*iter).nextQuaternary, ia, ib); res != 0 {
+				return res
+			}
+		}
+	}
+	return 0
+}
+
+// Key returns the collation key for str.
+// Passing the buffer buf may avoid memory allocations.
+// The returned slice will point to an allocation in Buffer and will remain
+// valid until the next call to buf.Reset().
+func (c *Collator) Key(buf *Buffer, str []byte) []byte {
+	// See http://www.unicode.org/reports/tr10/#Main_Algorithm for more details.
+	buf.init()
+	return c.key(buf, c.getColElems(str))
+}
+
+// KeyFromString returns the collation key for str.
+// Passing the buffer buf may avoid memory allocations.
+// The returned slice will point to an allocation in Buffer and will retain
+// valid until the next call to buf.ResetKeys().
+func (c *Collator) KeyFromString(buf *Buffer, str string) []byte {
+	// See http://www.unicode.org/reports/tr10/#Main_Algorithm for more details.
+	buf.init()
+	return c.key(buf, c.getColElemsString(str))
+}
+
+func (c *Collator) key(buf *Buffer, w []colltab.Elem) []byte {
+	processWeights(c.alternate, c.t.Top(), w)
+	kn := len(buf.key)
+	c.keyFromElems(buf, w)
+	return buf.key[kn:]
+}
+
+func (c *Collator) getColElems(str []byte) []colltab.Elem {
+	i := c.iter(0)
+	i.SetInput(str)
+	for i.Next() {
+	}
+	return i.Elems
+}
+
+func (c *Collator) getColElemsString(str string) []colltab.Elem {
+	i := c.iter(0)
+	i.SetInputString(str)
+	for i.Next() {
+	}
+	return i.Elems
+}
+
+type iter struct {
+	wa [512]colltab.Elem
+
+	colltab.Iter
+	pce int
+}
+
+func (i *iter) init(c *Collator) {
+	i.Weighter = c.t
+	i.Elems = i.wa[:0]
+}
+
+func (i *iter) nextPrimary() int {
+	for {
+		for ; i.pce < i.N; i.pce++ {
+			if v := i.Elems[i.pce].Primary(); v != 0 {
+				i.pce++
+				return v
+			}
+		}
+		if !i.Next() {
+			return 0
+		}
+	}
+	panic("should not reach here")
+}
+
+func (i *iter) nextSecondary() int {
+	for ; i.pce < len(i.Elems); i.pce++ {
+		if v := i.Elems[i.pce].Secondary(); v != 0 {
+			i.pce++
+			return v
+		}
+	}
+	return 0
+}
+
+func (i *iter) prevSecondary() int {
+	for ; i.pce < len(i.Elems); i.pce++ {
+		if v := i.Elems[len(i.Elems)-i.pce-1].Secondary(); v != 0 {
+			i.pce++
+			return v
+		}
+	}
+	return 0
+}
+
+func (i *iter) nextTertiary() int {
+	for ; i.pce < len(i.Elems); i.pce++ {
+		if v := i.Elems[i.pce].Tertiary(); v != 0 {
+			i.pce++
+			return int(v)
+		}
+	}
+	return 0
+}
+
+func (i *iter) nextQuaternary() int {
+	for ; i.pce < len(i.Elems); i.pce++ {
+		if v := i.Elems[i.pce].Quaternary(); v != 0 {
+			i.pce++
+			return v
+		}
+	}
+	return 0
+}
+
+func appendPrimary(key []byte, p int) []byte {
+	// Convert to variable length encoding; supports up to 23 bits.
+	if p <= 0x7FFF {
+		key = append(key, uint8(p>>8), uint8(p))
+	} else {
+		key = append(key, uint8(p>>16)|0x80, uint8(p>>8), uint8(p))
+	}
+	return key
+}
+
+// keyFromElems converts the weights ws to a compact sequence of bytes.
+// The result will be appended to the byte buffer in buf.
+func (c *Collator) keyFromElems(buf *Buffer, ws []colltab.Elem) {
+	for _, v := range ws {
+		if w := v.Primary(); w > 0 {
+			buf.key = appendPrimary(buf.key, w)
+		}
+	}
+	if !c.ignore[colltab.Secondary] {
+		buf.key = append(buf.key, 0, 0)
+		// TODO: we can use one 0 if we can guarantee that all non-zero weights are > 0xFF.
+		if !c.backwards {
+			for _, v := range ws {
+				if w := v.Secondary(); w > 0 {
+					buf.key = append(buf.key, uint8(w>>8), uint8(w))
+				}
+			}
+		} else {
+			for i := len(ws) - 1; i >= 0; i-- {
+				if w := ws[i].Secondary(); w > 0 {
+					buf.key = append(buf.key, uint8(w>>8), uint8(w))
+				}
+			}
+		}
+	} else if c.caseLevel {
+		buf.key = append(buf.key, 0, 0)
+	}
+	if !c.ignore[colltab.Tertiary] || c.caseLevel {
+		buf.key = append(buf.key, 0, 0)
+		for _, v := range ws {
+			if w := v.Tertiary(); w > 0 {
+				buf.key = append(buf.key, uint8(w))
+			}
+		}
+		// Derive the quaternary weights from the options and other levels.
+		// Note that we represent MaxQuaternary as 0xFF. The first byte of the
+		// representation of a primary weight is always smaller than 0xFF,
+		// so using this single byte value will compare correctly.
+		if !c.ignore[colltab.Quaternary] && c.alternate >= altShifted {
+			if c.alternate == altShiftTrimmed {
+				lastNonFFFF := len(buf.key)
+				buf.key = append(buf.key, 0)
+				for _, v := range ws {
+					if w := v.Quaternary(); w == colltab.MaxQuaternary {
+						buf.key = append(buf.key, 0xFF)
+					} else if w > 0 {
+						buf.key = appendPrimary(buf.key, w)
+						lastNonFFFF = len(buf.key)
+					}
+				}
+				buf.key = buf.key[:lastNonFFFF]
+			} else {
+				buf.key = append(buf.key, 0)
+				for _, v := range ws {
+					if w := v.Quaternary(); w == colltab.MaxQuaternary {
+						buf.key = append(buf.key, 0xFF)
+					} else if w > 0 {
+						buf.key = appendPrimary(buf.key, w)
+					}
+				}
+			}
+		}
+	}
+}
+
+func processWeights(vw alternateHandling, top uint32, wa []colltab.Elem) {
+	ignore := false
+	vtop := int(top)
+	switch vw {
+	case altShifted, altShiftTrimmed:
+		for i := range wa {
+			if p := wa[i].Primary(); p <= vtop && p != 0 {
+				wa[i] = colltab.MakeQuaternary(p)
+				ignore = true
+			} else if p == 0 {
+				if ignore {
+					wa[i] = colltab.Ignore
+				}
+			} else {
+				ignore = false
+			}
+		}
+	case altBlanked:
+		for i := range wa {
+			if p := wa[i].Primary(); p <= vtop && (ignore || p != 0) {
+				wa[i] = colltab.Ignore
+				ignore = true
+			} else {
+				ignore = false
+			}
+		}
+	}
+}