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authorMichael Muré <batolettre@gmail.com>2019-11-03 14:00:35 +0100
committerMichael Muré <batolettre@gmail.com>2019-11-03 14:00:35 +0100
commitf72a9dc62ba20546b2cdeb466434fc1900741a4f (patch)
tree8b68dc12c312d0a1fe6d5b1a1388cee82d44c634 /util/text/text.go
parent809abf9244f64683fe2d9f8489a4dcff0904d5b5 (diff)
downloadgit-bug-f72a9dc62ba20546b2cdeb466434fc1900741a4f.tar.gz
switch to go-term-text to fix bad underflow for label rendering
Diffstat (limited to 'util/text/text.go')
-rw-r--r--util/text/text.go330
1 files changed, 0 insertions, 330 deletions
diff --git a/util/text/text.go b/util/text/text.go
deleted file mode 100644
index 39584d5d..00000000
--- a/util/text/text.go
+++ /dev/null
@@ -1,330 +0,0 @@
-package text
-
-import (
- "github.com/mattn/go-runewidth"
- "strings"
- "unicode/utf8"
-)
-
-// Force runewidth not to treat ambiguous runes as wide chars, so that things
-// like unicode ellipsis/up/down/left/right glyphs can have correct runewidth
-// and can be displayed correctly in terminals.
-func init() {
- runewidth.DefaultCondition.EastAsianWidth = false
-}
-
-// Wrap a text for an exact line size
-// Handle properly terminal color escape code
-func Wrap(text string, lineWidth int) (string, int) {
- return WrapLeftPadded(text, lineWidth, 0)
-}
-
-// Wrap a text for an exact line size with a left padding
-// Handle properly terminal color escape code
-func WrapLeftPadded(text string, lineWidth int, leftPad int) (string, int) {
- var lines []string
- nbLine := 0
- pad := strings.Repeat(" ", leftPad)
-
- // tabs are formatted as 4 spaces
- text = strings.Replace(text, "\t", " ", -1)
- // NOTE: text is first segmented into lines so that softwrapLine can handle.
- for _, line := range strings.Split(text, "\n") {
- if line == "" || strings.TrimSpace(line) == "" {
- lines = append(lines, "")
- nbLine++
- } else {
- wrapped := softwrapLine(line, lineWidth-leftPad)
- firstLine := true
- for _, seg := range strings.Split(wrapped, "\n") {
- if firstLine {
- lines = append(lines, pad+strings.TrimRight(seg, " "))
- firstLine = false
- } else {
- lines = append(lines, pad+strings.TrimSpace(seg))
- }
- nbLine++
- }
- }
- }
- return strings.Join(lines, "\n"), nbLine
-}
-
-// Break a line into several lines so that each line consumes at most
-// 'textWidth' cells. Lines break at groups of white spaces and multibyte
-// chars. Nothing is removed from the original text so that it behaves like a
-// softwrap.
-//
-// Required: The line shall not contain '\n'
-//
-// WRAPPING ALGORITHM: The line is broken into non-breakable chunks, then line
-// breaks ("\n") are inserted between these groups so that the total length
-// between breaks does not exceed the required width. Words that are longer than
-// the textWidth are broken into pieces no longer than textWidth.
-//
-func softwrapLine(line string, textWidth int) string {
- // NOTE: terminal escapes are stripped out of the line so the algorithm is
- // simpler. Do not try to mix them in the wrapping algorithm, as it can get
- // complicated quickly.
- line1, termEscapes := extractTermEscapes(line)
-
- chunks := segmentLine(line1)
- // Reverse the chunk array so we can use it as a stack.
- for i, j := 0, len(chunks)-1; i < j; i, j = i+1, j-1 {
- chunks[i], chunks[j] = chunks[j], chunks[i]
- }
- var line2 string = ""
- var width int = 0
- for len(chunks) > 0 {
- thisWord := chunks[len(chunks)-1]
- wl := wordLen(thisWord)
- if width+wl <= textWidth {
- line2 += chunks[len(chunks)-1]
- chunks = chunks[:len(chunks)-1]
- width += wl
- if width == textWidth && len(chunks) > 0 {
- // NOTE: new line begins when current line is full and there are more
- // chunks to come.
- line2 += "\n"
- width = 0
- }
- } else if wl > textWidth {
- // NOTE: By default, long words are splited to fill the remaining space.
- // But if the long words is the first non-space word in the middle of the
- // line, preceeding spaces shall not be counted in word spliting.
- splitWidth := textWidth - width
- if strings.HasSuffix(line2, "\n"+strings.Repeat(" ", width)) {
- splitWidth += width
- }
- left, right := splitWord(chunks[len(chunks)-1], splitWidth)
- chunks[len(chunks)-1] = right
- line2 += left + "\n"
- width = 0
- } else {
- line2 += "\n"
- width = 0
- }
- }
-
- line3 := applyTermEscapes(line2, termEscapes)
- return line3
-}
-
-// EscapeItem: Storage of terminal escapes in a line. 'item' is the actural
-// escape command, and 'pos' is the index in the rune array where the 'item'
-// shall be inserted back. For example, the escape item in "F\x1b33mox" is
-// {"\x1b33m", 1}.
-type escapeItem struct {
- item string
- pos int
-}
-
-// Extract terminal escapes out of a line, returns a new line without terminal
-// escapes and a slice of escape items. The terminal escapes can be inserted
-// back into the new line at rune index 'item.pos' to recover the original line.
-//
-// Required: The line shall not contain "\n"
-//
-func extractTermEscapes(line string) (string, []escapeItem) {
- var termEscapes []escapeItem
- var line1 string
-
- pos := 0
- item := ""
- occupiedRuneCount := 0
- inEscape := false
- for i, r := range []rune(line) {
- if r == '\x1b' {
- pos = i
- item = string(r)
- inEscape = true
- continue
- }
- if inEscape {
- item += string(r)
- if r == 'm' {
- termEscapes = append(termEscapes, escapeItem{item, pos - occupiedRuneCount})
- occupiedRuneCount += utf8.RuneCountInString(item)
- inEscape = false
- }
- continue
- }
- line1 += string(r)
- }
-
- return line1, termEscapes
-}
-
-// Apply the extracted terminal escapes to the edited line. The only edit
-// allowed is to insert "\n" like that in softwrapLine. Callers shall ensure
-// this since this function is not able to check it.
-func applyTermEscapes(line string, escapes []escapeItem) string {
- if len(escapes) == 0 {
- return line
- }
-
- var out string = ""
-
- currPos := 0
- currItem := 0
- for _, r := range line {
- if currItem < len(escapes) && currPos == escapes[currItem].pos {
- // NOTE: We avoid terminal escapes at the end of a line by move them one
- // pass the end of line, so that algorithms who trim right spaces are
- // happy. But algorithms who trim left spaces are still unhappy.
- if r == '\n' {
- out += "\n" + escapes[currItem].item
- } else {
- out += escapes[currItem].item + string(r)
- currPos++
- }
- currItem++
- } else {
- if r != '\n' {
- currPos++
- }
- out += string(r)
- }
- }
-
- // Don't forget the trailing escape, if any.
- if currItem == len(escapes)-1 && currPos == escapes[currItem].pos {
- out += escapes[currItem].item
- }
-
- return out
-}
-
-// Segment a line into chunks, where each chunk consists of chars with the same
-// type and is not breakable.
-func segmentLine(s string) []string {
- var chunks []string
-
- var word string
- wordType := none
- flushWord := func() {
- chunks = append(chunks, word)
- word = ""
- wordType = none
- }
-
- for _, r := range s {
- // A WIDE_CHAR itself constitutes a chunk.
- thisType := runeType(r)
- if thisType == wideChar {
- if wordType != none {
- flushWord()
- }
- chunks = append(chunks, string(r))
- continue
- }
- // Other type of chunks starts with a char of that type, and ends with a
- // char with different type or end of string.
- if thisType != wordType {
- if wordType != none {
- flushWord()
- }
- word = string(r)
- wordType = thisType
- } else {
- word += string(r)
- }
- }
- if word != "" {
- flushWord()
- }
-
- return chunks
-}
-
-// Rune categories
-//
-// These categories are so defined that each category forms a non-breakable
-// chunk. It IS NOT the same as unicode code point categories.
-//
-const (
- none int = iota
- wideChar
- invisible
- shortUnicode
- space
- visibleAscii
-)
-
-// Determine the category of a rune.
-func runeType(r rune) int {
- rw := runewidth.RuneWidth(r)
- if rw > 1 {
- return wideChar
- } else if rw == 0 {
- return invisible
- } else if r > 127 {
- return shortUnicode
- } else if r == ' ' {
- return space
- } else {
- return visibleAscii
- }
-}
-
-// wordLen return the length of a word, while ignoring the terminal escape
-// sequences
-func wordLen(word string) int {
- length := 0
- escape := false
-
- for _, char := range word {
- if char == '\x1b' {
- escape = true
- }
- if !escape {
- length += runewidth.RuneWidth(rune(char))
- }
- if char == 'm' {
- escape = false
- }
- }
-
- return length
-}
-
-// splitWord split a word at the given length, while ignoring the terminal escape sequences
-func splitWord(word string, length int) (string, string) {
- runes := []rune(word)
- var result []rune
- added := 0
- escape := false
-
- if length == 0 {
- return "", word
- }
-
- for _, r := range runes {
- if r == '\x1b' {
- escape = true
- }
-
- width := runewidth.RuneWidth(r)
- if width+added > length {
- // wide character made the length overflow
- break
- }
-
- result = append(result, r)
-
- if !escape {
- added += width
- if added >= length {
- break
- }
- }
-
- if r == 'm' {
- escape = false
- }
- }
-
- leftover := runes[len(result):]
-
- return string(result), string(leftover)
-}