diff options
Diffstat (limited to 'Godeps/_workspace/src/github.com/peterh/liner/line.go')
-rw-r--r-- | Godeps/_workspace/src/github.com/peterh/liner/line.go | 864 |
1 files changed, 864 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/github.com/peterh/liner/line.go b/Godeps/_workspace/src/github.com/peterh/liner/line.go new file mode 100644 index 000000000..a70fb59e5 --- /dev/null +++ b/Godeps/_workspace/src/github.com/peterh/liner/line.go @@ -0,0 +1,864 @@ +// +build windows linux darwin openbsd freebsd netbsd + +package liner + +import ( + "container/ring" + "errors" + "fmt" + "io" + "strings" + "unicode" + "unicode/utf8" +) + +type action int + +const ( + left action = iota + right + up + down + home + end + insert + del + pageUp + pageDown + f1 + f2 + f3 + f4 + f5 + f6 + f7 + f8 + f9 + f10 + f11 + f12 + altY + shiftTab + wordLeft + wordRight + winch + unknown +) + +const ( + ctrlA = 1 + ctrlB = 2 + ctrlC = 3 + ctrlD = 4 + ctrlE = 5 + ctrlF = 6 + ctrlG = 7 + ctrlH = 8 + tab = 9 + lf = 10 + ctrlK = 11 + ctrlL = 12 + cr = 13 + ctrlN = 14 + ctrlO = 15 + ctrlP = 16 + ctrlQ = 17 + ctrlR = 18 + ctrlS = 19 + ctrlT = 20 + ctrlU = 21 + ctrlV = 22 + ctrlW = 23 + ctrlX = 24 + ctrlY = 25 + ctrlZ = 26 + esc = 27 + bs = 127 +) + +const ( + beep = "\a" +) + +type tabDirection int + +const ( + tabForward tabDirection = iota + tabReverse +) + +func (s *State) refresh(prompt []rune, buf []rune, pos int) error { + s.cursorPos(0) + _, err := fmt.Print(string(prompt)) + if err != nil { + return err + } + + pLen := countGlyphs(prompt) + bLen := countGlyphs(buf) + pos = countGlyphs(buf[:pos]) + if pLen+bLen < s.columns { + _, err = fmt.Print(string(buf)) + s.eraseLine() + s.cursorPos(pLen + pos) + } else { + // Find space available + space := s.columns - pLen + space-- // space for cursor + start := pos - space/2 + end := start + space + if end > bLen { + end = bLen + start = end - space + } + if start < 0 { + start = 0 + end = space + } + pos -= start + + // Leave space for markers + if start > 0 { + start++ + } + if end < bLen { + end-- + } + startRune := len(getPrefixGlyphs(buf, start)) + line := getPrefixGlyphs(buf[startRune:], end-start) + + // Output + if start > 0 { + fmt.Print("{") + } + fmt.Print(string(line)) + if end < bLen { + fmt.Print("}") + } + + // Set cursor position + s.eraseLine() + s.cursorPos(pLen + pos) + } + return err +} + +func longestCommonPrefix(strs []string) string { + if len(strs) == 0 { + return "" + } + longest := strs[0] + + for _, str := range strs[1:] { + for !strings.HasPrefix(str, longest) { + longest = longest[:len(longest)-1] + } + } + // Remove trailing partial runes + longest = strings.TrimRight(longest, "\uFFFD") + return longest +} + +func (s *State) circularTabs(items []string) func(tabDirection) (string, error) { + item := -1 + return func(direction tabDirection) (string, error) { + if direction == tabForward { + if item < len(items)-1 { + item++ + } else { + item = 0 + } + } else if direction == tabReverse { + if item > 0 { + item-- + } else { + item = len(items) - 1 + } + } + return items[item], nil + } +} + +func (s *State) printedTabs(items []string) func(tabDirection) (string, error) { + numTabs := 1 + prefix := longestCommonPrefix(items) + return func(direction tabDirection) (string, error) { + if len(items) == 1 { + return items[0], nil + } + + if numTabs == 2 { + if len(items) > 100 { + fmt.Printf("\nDisplay all %d possibilities? (y or n) ", len(items)) + for { + next, err := s.readNext() + if err != nil { + return prefix, err + } + + if key, ok := next.(rune); ok { + if unicode.ToLower(key) == 'n' { + return prefix, nil + } else if unicode.ToLower(key) == 'y' { + break + } + } + } + } + fmt.Println("") + maxWidth := 0 + for _, item := range items { + if len(item) >= maxWidth { + maxWidth = len(item) + 1 + } + } + + numColumns := s.columns / maxWidth + numRows := len(items) / numColumns + if len(items)%numColumns > 0 { + numRows++ + } + + if len(items) <= numColumns { + maxWidth = 0 + } + for i := 0; i < numRows; i++ { + for j := 0; j < numColumns*numRows; j += numRows { + if i+j < len(items) { + if maxWidth > 0 { + fmt.Printf("%-*s", maxWidth, items[i+j]) + } else { + fmt.Printf("%v ", items[i+j]) + } + } + } + fmt.Println("") + } + } else { + numTabs++ + } + return prefix, nil + } +} + +func (s *State) tabComplete(p []rune, line []rune, pos int) ([]rune, int, interface{}, error) { + if s.completer == nil { + return line, pos, rune(esc), nil + } + head, list, tail := s.completer(string(line), pos) + if len(list) <= 0 { + return line, pos, rune(esc), nil + } + hl := utf8.RuneCountInString(head) + if len(list) == 1 { + s.refresh(p, []rune(head+list[0]+tail), hl+utf8.RuneCountInString(list[0])) + return []rune(head + list[0] + tail), hl + utf8.RuneCountInString(list[0]), rune(esc), nil + } + + direction := tabForward + tabPrinter := s.circularTabs(list) + if s.tabStyle == TabPrints { + tabPrinter = s.printedTabs(list) + } + + for { + pick, err := tabPrinter(direction) + if err != nil { + return line, pos, rune(esc), err + } + s.refresh(p, []rune(head+pick+tail), hl+utf8.RuneCountInString(pick)) + + next, err := s.readNext() + if err != nil { + return line, pos, rune(esc), err + } + if key, ok := next.(rune); ok { + if key == tab { + direction = tabForward + continue + } + if key == esc { + return line, pos, rune(esc), nil + } + } + if a, ok := next.(action); ok && a == shiftTab { + direction = tabReverse + continue + } + return []rune(head + pick + tail), hl + utf8.RuneCountInString(pick), next, nil + } + // Not reached + return line, pos, rune(esc), nil +} + +// reverse intelligent search, implements a bash-like history search. +func (s *State) reverseISearch(origLine []rune, origPos int) ([]rune, int, interface{}, error) { + p := "(reverse-i-search)`': " + s.refresh([]rune(p), origLine, origPos) + + line := []rune{} + pos := 0 + foundLine := string(origLine) + foundPos := origPos + + getLine := func() ([]rune, []rune, int) { + search := string(line) + prompt := "(reverse-i-search)`%s': " + return []rune(fmt.Sprintf(prompt, search)), []rune(foundLine), foundPos + } + + history, positions := s.getHistoryByPattern(string(line)) + historyPos := len(history) - 1 + + for { + next, err := s.readNext() + if err != nil { + return []rune(foundLine), foundPos, rune(esc), err + } + + switch v := next.(type) { + case rune: + switch v { + case ctrlR: // Search backwards + if historyPos > 0 && historyPos < len(history) { + historyPos-- + foundLine = history[historyPos] + foundPos = positions[historyPos] + } else { + fmt.Print(beep) + } + case ctrlS: // Search forward + if historyPos < len(history)-1 && historyPos >= 0 { + historyPos++ + foundLine = history[historyPos] + foundPos = positions[historyPos] + } else { + fmt.Print(beep) + } + case ctrlH, bs: // Backspace + if pos <= 0 { + fmt.Print(beep) + } else { + n := len(getSuffixGlyphs(line[:pos], 1)) + line = append(line[:pos-n], line[pos:]...) + pos -= n + + // For each char deleted, display the last matching line of history + history, positions := s.getHistoryByPattern(string(line)) + historyPos = len(history) - 1 + if len(history) > 0 { + foundLine = history[historyPos] + foundPos = positions[historyPos] + } else { + foundLine = "" + foundPos = 0 + } + } + case ctrlG: // Cancel + return origLine, origPos, rune(esc), err + + case tab, cr, lf, ctrlA, ctrlB, ctrlD, ctrlE, ctrlF, ctrlK, + ctrlL, ctrlN, ctrlO, ctrlP, ctrlQ, ctrlT, ctrlU, ctrlV, ctrlW, ctrlX, ctrlY, ctrlZ: + fallthrough + case 0, ctrlC, esc, 28, 29, 30, 31: + return []rune(foundLine), foundPos, next, err + default: + line = append(line[:pos], append([]rune{v}, line[pos:]...)...) + pos++ + + // For each keystroke typed, display the last matching line of history + history, positions = s.getHistoryByPattern(string(line)) + historyPos = len(history) - 1 + if len(history) > 0 { + foundLine = history[historyPos] + foundPos = positions[historyPos] + } else { + foundLine = "" + foundPos = 0 + } + } + case action: + return []rune(foundLine), foundPos, next, err + } + s.refresh(getLine()) + } +} + +// addToKillRing adds some text to the kill ring. If mode is 0 it adds it to a +// new node in the end of the kill ring, and move the current pointer to the new +// node. If mode is 1 or 2 it appends or prepends the text to the current entry +// of the killRing. +func (s *State) addToKillRing(text []rune, mode int) { + // Don't use the same underlying array as text + killLine := make([]rune, len(text)) + copy(killLine, text) + + // Point killRing to a newNode, procedure depends on the killring state and + // append mode. + if mode == 0 { // Add new node to killRing + if s.killRing == nil { // if killring is empty, create a new one + s.killRing = ring.New(1) + } else if s.killRing.Len() >= KillRingMax { // if killring is "full" + s.killRing = s.killRing.Next() + } else { // Normal case + s.killRing.Link(ring.New(1)) + s.killRing = s.killRing.Next() + } + } else { + if s.killRing == nil { // if killring is empty, create a new one + s.killRing = ring.New(1) + s.killRing.Value = []rune{} + } + if mode == 1 { // Append to last entry + killLine = append(s.killRing.Value.([]rune), killLine...) + } else if mode == 2 { // Prepend to last entry + killLine = append(killLine, s.killRing.Value.([]rune)...) + } + } + + // Save text in the current killring node + s.killRing.Value = killLine +} + +func (s *State) yank(p []rune, text []rune, pos int) ([]rune, int, interface{}, error) { + if s.killRing == nil { + return text, pos, rune(esc), nil + } + + lineStart := text[:pos] + lineEnd := text[pos:] + var line []rune + + for { + value := s.killRing.Value.([]rune) + line = make([]rune, 0) + line = append(line, lineStart...) + line = append(line, value...) + line = append(line, lineEnd...) + + pos = len(lineStart) + len(value) + s.refresh(p, line, pos) + + next, err := s.readNext() + if err != nil { + return line, pos, next, err + } + + switch v := next.(type) { + case rune: + return line, pos, next, nil + case action: + switch v { + case altY: + s.killRing = s.killRing.Prev() + default: + return line, pos, next, nil + } + } + } + + return line, pos, esc, nil +} + +// Prompt displays p, and then waits for user input. Prompt allows line editing +// if the terminal supports it. +func (s *State) Prompt(prompt string) (string, error) { + if s.inputRedirected { + return s.promptUnsupported(prompt) + } + if s.outputRedirected { + return "", ErrNotTerminalOutput + } + if !s.terminalSupported { + return s.promptUnsupported(prompt) + } + + s.historyMutex.RLock() + defer s.historyMutex.RUnlock() + + s.startPrompt() + defer s.stopPrompt() + s.getColumns() + + fmt.Print(prompt) + p := []rune(prompt) + var line []rune + pos := 0 + historyEnd := "" + prefixHistory := s.getHistoryByPrefix(string(line)) + historyPos := len(prefixHistory) + historyAction := false // used to mark history related actions + killAction := 0 // used to mark kill related actions +mainLoop: + for { + next, err := s.readNext() + haveNext: + if err != nil { + return "", err + } + + historyAction = false + switch v := next.(type) { + case rune: + switch v { + case cr, lf: + fmt.Println() + break mainLoop + case ctrlA: // Start of line + pos = 0 + s.refresh(p, line, pos) + case ctrlE: // End of line + pos = len(line) + s.refresh(p, line, pos) + case ctrlB: // left + if pos > 0 { + pos -= len(getSuffixGlyphs(line[:pos], 1)) + s.refresh(p, line, pos) + } else { + fmt.Print(beep) + } + case ctrlF: // right + if pos < len(line) { + pos += len(getPrefixGlyphs(line[pos:], 1)) + s.refresh(p, line, pos) + } else { + fmt.Print(beep) + } + case ctrlD: // del + if pos == 0 && len(line) == 0 { + // exit + return "", io.EOF + } + + // ctrlD is a potential EOF, so the rune reader shuts down. + // Therefore, if it isn't actually an EOF, we must re-startPrompt. + s.restartPrompt() + + if pos >= len(line) { + fmt.Print(beep) + } else { + n := len(getPrefixGlyphs(line[pos:], 1)) + line = append(line[:pos], line[pos+n:]...) + s.refresh(p, line, pos) + } + case ctrlK: // delete remainder of line + if pos >= len(line) { + fmt.Print(beep) + } else { + if killAction > 0 { + s.addToKillRing(line[pos:], 1) // Add in apend mode + } else { + s.addToKillRing(line[pos:], 0) // Add in normal mode + } + + killAction = 2 // Mark that there was a kill action + line = line[:pos] + s.refresh(p, line, pos) + } + case ctrlP: // up + historyAction = true + if historyPos > 0 { + if historyPos == len(prefixHistory) { + historyEnd = string(line) + } + historyPos-- + line = []rune(prefixHistory[historyPos]) + pos = len(line) + s.refresh(p, line, pos) + } else { + fmt.Print(beep) + } + case ctrlN: // down + historyAction = true + if historyPos < len(prefixHistory) { + historyPos++ + if historyPos == len(prefixHistory) { + line = []rune(historyEnd) + } else { + line = []rune(prefixHistory[historyPos]) + } + pos = len(line) + s.refresh(p, line, pos) + } else { + fmt.Print(beep) + } + case ctrlT: // transpose prev glyph with glyph under cursor + if len(line) < 2 || pos < 1 { + fmt.Print(beep) + } else { + if pos == len(line) { + pos -= len(getSuffixGlyphs(line, 1)) + } + prev := getSuffixGlyphs(line[:pos], 1) + next := getPrefixGlyphs(line[pos:], 1) + scratch := make([]rune, len(prev)) + copy(scratch, prev) + copy(line[pos-len(prev):], next) + copy(line[pos-len(prev)+len(next):], scratch) + pos += len(next) + s.refresh(p, line, pos) + } + case ctrlL: // clear screen + s.eraseScreen() + s.refresh(p, line, pos) + case ctrlC: // reset + fmt.Println("^C") + if s.ctrlCAborts { + return "", ErrPromptAborted + } + line = line[:0] + pos = 0 + fmt.Print(prompt) + s.restartPrompt() + case ctrlH, bs: // Backspace + if pos <= 0 { + fmt.Print(beep) + } else { + n := len(getSuffixGlyphs(line[:pos], 1)) + line = append(line[:pos-n], line[pos:]...) + pos -= n + s.refresh(p, line, pos) + } + case ctrlU: // Erase line before cursor + if killAction > 0 { + s.addToKillRing(line[:pos], 2) // Add in prepend mode + } else { + s.addToKillRing(line[:pos], 0) // Add in normal mode + } + + killAction = 2 // Mark that there was some killing + line = line[pos:] + pos = 0 + s.refresh(p, line, pos) + case ctrlW: // Erase word + if pos == 0 { + fmt.Print(beep) + break + } + // Remove whitespace to the left + var buf []rune // Store the deleted chars in a buffer + for { + if pos == 0 || !unicode.IsSpace(line[pos-1]) { + break + } + buf = append(buf, line[pos-1]) + line = append(line[:pos-1], line[pos:]...) + pos-- + } + // Remove non-whitespace to the left + for { + if pos == 0 || unicode.IsSpace(line[pos-1]) { + break + } + buf = append(buf, line[pos-1]) + line = append(line[:pos-1], line[pos:]...) + pos-- + } + // Invert the buffer and save the result on the killRing + var newBuf []rune + for i := len(buf) - 1; i >= 0; i-- { + newBuf = append(newBuf, buf[i]) + } + if killAction > 0 { + s.addToKillRing(newBuf, 2) // Add in prepend mode + } else { + s.addToKillRing(newBuf, 0) // Add in normal mode + } + killAction = 2 // Mark that there was some killing + + s.refresh(p, line, pos) + case ctrlY: // Paste from Yank buffer + line, pos, next, err = s.yank(p, line, pos) + goto haveNext + case ctrlR: // Reverse Search + line, pos, next, err = s.reverseISearch(line, pos) + s.refresh(p, line, pos) + goto haveNext + case tab: // Tab completion + line, pos, next, err = s.tabComplete(p, line, pos) + goto haveNext + // Catch keys that do nothing, but you don't want them to beep + case esc: + // DO NOTHING + // Unused keys + case ctrlG, ctrlO, ctrlQ, ctrlS, ctrlV, ctrlX, ctrlZ: + fallthrough + // Catch unhandled control codes (anything <= 31) + case 0, 28, 29, 30, 31: + fmt.Print(beep) + default: + if pos == len(line) && len(p)+len(line) < s.columns-1 { + line = append(line, v) + fmt.Printf("%c", v) + pos++ + } else { + line = append(line[:pos], append([]rune{v}, line[pos:]...)...) + pos++ + s.refresh(p, line, pos) + } + } + case action: + switch v { + case del: + if pos >= len(line) { + fmt.Print(beep) + } else { + n := len(getPrefixGlyphs(line[pos:], 1)) + line = append(line[:pos], line[pos+n:]...) + } + case left: + if pos > 0 { + pos -= len(getSuffixGlyphs(line[:pos], 1)) + } else { + fmt.Print(beep) + } + case wordLeft: + if pos > 0 { + for { + pos-- + if pos == 0 || unicode.IsSpace(line[pos-1]) { + break + } + } + } else { + fmt.Print(beep) + } + case right: + if pos < len(line) { + pos += len(getPrefixGlyphs(line[pos:], 1)) + } else { + fmt.Print(beep) + } + case wordRight: + if pos < len(line) { + for { + pos++ + if pos == len(line) || unicode.IsSpace(line[pos]) { + break + } + } + } else { + fmt.Print(beep) + } + case up: + historyAction = true + if historyPos > 0 { + if historyPos == len(prefixHistory) { + historyEnd = string(line) + } + historyPos-- + line = []rune(prefixHistory[historyPos]) + pos = len(line) + } else { + fmt.Print(beep) + } + case down: + historyAction = true + if historyPos < len(prefixHistory) { + historyPos++ + if historyPos == len(prefixHistory) { + line = []rune(historyEnd) + } else { + line = []rune(prefixHistory[historyPos]) + } + pos = len(line) + } else { + fmt.Print(beep) + } + case home: // Start of line + pos = 0 + case end: // End of line + pos = len(line) + } + s.refresh(p, line, pos) + } + if !historyAction { + prefixHistory = s.getHistoryByPrefix(string(line)) + historyPos = len(prefixHistory) + } + if killAction > 0 { + killAction-- + } + } + return string(line), nil +} + +// PasswordPrompt displays p, and then waits for user input. The input typed by +// the user is not displayed in the terminal. +func (s *State) PasswordPrompt(prompt string) (string, error) { + if s.inputRedirected { + return s.promptUnsupported(prompt) + } + if s.outputRedirected { + return "", ErrNotTerminalOutput + } + if !s.terminalSupported { + return "", errors.New("liner: function not supported in this terminal") + } + + s.startPrompt() + defer s.stopPrompt() + s.getColumns() + + fmt.Print(prompt) + p := []rune(prompt) + var line []rune + pos := 0 + +mainLoop: + for { + next, err := s.readNext() + if err != nil { + return "", err + } + + switch v := next.(type) { + case rune: + switch v { + case cr, lf: + fmt.Println() + break mainLoop + case ctrlD: // del + if pos == 0 && len(line) == 0 { + // exit + return "", io.EOF + } + + // ctrlD is a potential EOF, so the rune reader shuts down. + // Therefore, if it isn't actually an EOF, we must re-startPrompt. + s.restartPrompt() + case ctrlL: // clear screen + s.eraseScreen() + s.refresh(p, []rune{}, 0) + case ctrlH, bs: // Backspace + if pos <= 0 { + fmt.Print(beep) + } else { + n := len(getSuffixGlyphs(line[:pos], 1)) + line = append(line[:pos-n], line[pos:]...) + pos -= n + } + case ctrlC: + fmt.Println("^C") + if s.ctrlCAborts { + return "", ErrPromptAborted + } + line = line[:0] + pos = 0 + fmt.Print(prompt) + s.restartPrompt() + // Unused keys + case esc, tab, ctrlA, ctrlB, ctrlE, ctrlF, ctrlG, ctrlK, ctrlN, ctrlO, ctrlP, ctrlQ, ctrlR, ctrlS, + ctrlT, ctrlU, ctrlV, ctrlW, ctrlX, ctrlY, ctrlZ: + fallthrough + // Catch unhandled control codes (anything <= 31) + case 0, 28, 29, 30, 31: + fmt.Print(beep) + default: + line = append(line[:pos], append([]rune{v}, line[pos:]...)...) + pos++ + } + } + } + return string(line), nil +} |