mirror of
https://codeberg.org/forgejo/forgejo
synced 2024-12-05 02:54:46 +01:00
259 lines
5.2 KiB
Go
259 lines
5.2 KiB
Go
|
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 {
|
||
|
// func (t table) IncludesRune(r rune) 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)
|
||
|
}
|