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Diffstat (limited to 'vendor/github.com/mattn/go-runewidth/runewidth.go')
-rw-r--r--vendor/github.com/mattn/go-runewidth/runewidth.go257
1 files changed, 257 insertions, 0 deletions
diff --git a/vendor/github.com/mattn/go-runewidth/runewidth.go b/vendor/github.com/mattn/go-runewidth/runewidth.go
new file mode 100644
index 000000000..19f8e0449
--- /dev/null
+++ b/vendor/github.com/mattn/go-runewidth/runewidth.go
@@ -0,0 +1,257 @@
+package runewidth
+
+import (
+ "os"
+)
+
+//go:generate go run script/generate.go
+
+var (
+ // EastAsianWidth will be set true if the current locale is CJK
+ EastAsianWidth bool
+
+ // ZeroWidthJoiner is flag to set to use UTR#51 ZWJ
+ ZeroWidthJoiner bool
+
+ // DefaultCondition is a condition in current locale
+ DefaultCondition = &Condition{}
+)
+
+func init() {
+ handleEnv()
+}
+
+func handleEnv() {
+ env := os.Getenv("RUNEWIDTH_EASTASIAN")
+ if env == "" {
+ EastAsianWidth = IsEastAsian()
+ } else {
+ EastAsianWidth = env == "1"
+ }
+ // update DefaultCondition
+ DefaultCondition.EastAsianWidth = EastAsianWidth
+ DefaultCondition.ZeroWidthJoiner = ZeroWidthJoiner
+}
+
+type interval struct {
+ first rune
+ last rune
+}
+
+type table []interval
+
+func inTables(r rune, ts ...table) bool {
+ for _, t := range ts {
+ if inTable(r, t) {
+ return true
+ }
+ }
+ return false
+}
+
+func inTable(r rune, t table) bool {
+ if r < t[0].first {
+ return false
+ }
+
+ bot := 0
+ top := len(t) - 1
+ for top >= bot {
+ mid := (bot + top) >> 1
+
+ switch {
+ case t[mid].last < r:
+ bot = mid + 1
+ case t[mid].first > r:
+ top = mid - 1
+ default:
+ return true
+ }
+ }
+
+ return false
+}
+
+var private = table{
+ {0x00E000, 0x00F8FF}, {0x0F0000, 0x0FFFFD}, {0x100000, 0x10FFFD},
+}
+
+var nonprint = table{
+ {0x0000, 0x001F}, {0x007F, 0x009F}, {0x00AD, 0x00AD},
+ {0x070F, 0x070F}, {0x180B, 0x180E}, {0x200B, 0x200F},
+ {0x2028, 0x202E}, {0x206A, 0x206F}, {0xD800, 0xDFFF},
+ {0xFEFF, 0xFEFF}, {0xFFF9, 0xFFFB}, {0xFFFE, 0xFFFF},
+}
+
+// Condition have flag EastAsianWidth whether the current locale is CJK or not.
+type Condition struct {
+ EastAsianWidth bool
+ ZeroWidthJoiner bool
+}
+
+// NewCondition return new instance of Condition which is current locale.
+func NewCondition() *Condition {
+ return &Condition{
+ EastAsianWidth: EastAsianWidth,
+ ZeroWidthJoiner: ZeroWidthJoiner,
+ }
+}
+
+// RuneWidth returns the number of cells in r.
+// See http://www.unicode.org/reports/tr11/
+func (c *Condition) RuneWidth(r rune) int {
+ switch {
+ case r < 0 || r > 0x10FFFF || inTables(r, nonprint, combining, notassigned):
+ return 0
+ case (c.EastAsianWidth && IsAmbiguousWidth(r)) || inTables(r, doublewidth):
+ return 2
+ default:
+ return 1
+ }
+}
+
+func (c *Condition) stringWidth(s string) (width int) {
+ for _, r := range []rune(s) {
+ width += c.RuneWidth(r)
+ }
+ return width
+}
+
+func (c *Condition) stringWidthZeroJoiner(s string) (width int) {
+ r1, r2 := rune(0), rune(0)
+ for _, r := range []rune(s) {
+ if r == 0xFE0E || r == 0xFE0F {
+ continue
+ }
+ w := c.RuneWidth(r)
+ if r2 == 0x200D && inTables(r, emoji) && inTables(r1, emoji) {
+ if width < w {
+ width = w
+ }
+ } else {
+ width += w
+ }
+ r1, r2 = r2, r
+ }
+ return width
+}
+
+// StringWidth return width as you can see
+func (c *Condition) StringWidth(s string) (width int) {
+ if c.ZeroWidthJoiner {
+ return c.stringWidthZeroJoiner(s)
+ }
+ return c.stringWidth(s)
+}
+
+// Truncate return string truncated with w cells
+func (c *Condition) Truncate(s string, w int, tail string) string {
+ if c.StringWidth(s) <= w {
+ return s
+ }
+ r := []rune(s)
+ tw := c.StringWidth(tail)
+ w -= tw
+ width := 0
+ i := 0
+ for ; i < len(r); i++ {
+ cw := c.RuneWidth(r[i])
+ if width+cw > w {
+ break
+ }
+ width += cw
+ }
+ return string(r[0:i]) + tail
+}
+
+// Wrap return string wrapped with w cells
+func (c *Condition) Wrap(s string, w int) string {
+ width := 0
+ out := ""
+ for _, r := range []rune(s) {
+ cw := RuneWidth(r)
+ if r == '\n' {
+ out += string(r)
+ width = 0
+ continue
+ } else if width+cw > w {
+ out += "\n"
+ width = 0
+ out += string(r)
+ width += cw
+ continue
+ }
+ out += string(r)
+ width += cw
+ }
+ return out
+}
+
+// FillLeft return string filled in left by spaces in w cells
+func (c *Condition) FillLeft(s string, w int) string {
+ width := c.StringWidth(s)
+ count := w - width
+ if count > 0 {
+ b := make([]byte, count)
+ for i := range b {
+ b[i] = ' '
+ }
+ return string(b) + s
+ }
+ return s
+}
+
+// FillRight return string filled in left by spaces in w cells
+func (c *Condition) FillRight(s string, w int) string {
+ width := c.StringWidth(s)
+ count := w - width
+ if count > 0 {
+ b := make([]byte, count)
+ for i := range b {
+ b[i] = ' '
+ }
+ return s + string(b)
+ }
+ return s
+}
+
+// RuneWidth returns the number of cells in r.
+// See http://www.unicode.org/reports/tr11/
+func RuneWidth(r rune) int {
+ return DefaultCondition.RuneWidth(r)
+}
+
+// IsAmbiguousWidth returns whether is ambiguous width or not.
+func IsAmbiguousWidth(r rune) bool {
+ return inTables(r, private, ambiguous)
+}
+
+// IsNeutralWidth returns whether is neutral width or not.
+func IsNeutralWidth(r rune) bool {
+ return inTable(r, neutral)
+}
+
+// StringWidth return width as you can see
+func StringWidth(s string) (width int) {
+ return DefaultCondition.StringWidth(s)
+}
+
+// Truncate return string truncated with w cells
+func Truncate(s string, w int, tail string) string {
+ return DefaultCondition.Truncate(s, w, tail)
+}
+
+// Wrap return string wrapped with w cells
+func Wrap(s string, w int) string {
+ return DefaultCondition.Wrap(s, w)
+}
+
+// FillLeft return string filled in left by spaces in w cells
+func FillLeft(s string, w int) string {
+ return DefaultCondition.FillLeft(s, w)
+}
+
+// FillRight return string filled in left by spaces in w cells
+func FillRight(s string, w int) string {
+ return DefaultCondition.FillRight(s, w)
+}