Merge pull request #7 from chzyer/feature/add_vim_mode

add simple vim mode

README.md

@@ -24,10 +24,15 @@ You can read the source code in [example/main.go](https://github.com/chzyer/read
 
 # Todo
 
-* Vim mode
 * More funny examples
 * Support dumb/eterm-color terminal in emacs
 
+# Features
+* Support emacs/vi mode, almost all basic features that GNU-Readline is supported
+* zsh-style backward/forward history search
+* zsh-style completion
+* Readline auto refresh when others write to Stdout while editing(it needs specify the Stdout/Stderr provided by *readline.Instance to others).
+
 # Usage
 
 * Simplest example
@@ -139,7 +144,7 @@ for {
 # Shortcut
 
 `Meta`+`B` means press `Esc` and `n` separately.  
-Users can change that in terminal simulator(i.e. iTerm2) to `Alt`+`B`
+Users can change that in terminal simulator(i.e. iTerm2) to `Alt`+`B`  
 Notice: `Meta`+`B` is equals with `Alt`+`B` in windows.
 
 * Shortcut in normal mode

char.go

@@ -7,7 +7,7 @@ const (
 	CharDelete    = 4
 	CharLineEnd   = 5
 	CharForward   = 6
-	CharCancel    = 7
+	CharBell      = 7
 	CharCtrlH     = 8
 	CharTab       = 9
 	CharCtrlJ     = 10
@@ -26,8 +26,8 @@ const (
 )
 
 const (
-	MetaPrev rune = -iota - 1
-	MetaNext
+	MetaBackward rune = -iota - 1
+	MetaForward
 	MetaDelete
 	MetaBackspace
 	MetaTranspose

complete.go

@@ -127,7 +127,7 @@ func (o *opCompleter) HandleCompleteSelect(r rune) bool {
 		next = false
 	case CharTab, CharForward:
 		o.doSelect()
-	case CharCancel, CharInterrupt:
+	case CharBell, CharInterrupt:
 		o.ExitCompleteMode(true)
 		next = false
 	case CharNext:

example/main.go

@@ -20,6 +20,10 @@ bye
 }
 
 var completer = readline.NewPrefixCompleter(
+	readline.PcItem("mode",
+		readline.PcItem("vi"),
+		readline.PcItem("emacs"),
+	),
 	readline.PcItem("login"),
 	readline.PcItem("say",
 		readline.PcItem("hello"),
@@ -52,8 +56,23 @@ func main() {
 		if err != nil {
 			break
 		}
-
+		line = strings.TrimSpace(line)
 		switch {
+		case strings.HasPrefix(line, "mode "):
+			switch line[5:] {
+			case "vi":
+				l.SetVimMode(true)
+			case "emacs":
+				l.SetVimMode(false)
+			default:
+				println("invalid mode:", line[5:])
+			}
+		case line == "mode":
+			if l.IsVimMode() {
+				println("current mode: vim")
+			} else {
+				println("current mode: emacs")
+			}
 		case line == "login":
 			pswd, err := l.ReadPassword("please enter your password: ")
 			if err != nil {

operation.go

@@ -18,6 +18,7 @@ type Operation struct {
 	*opHistory
 	*opSearch
 	*opCompleter
+	*opVim
 }
 
 type wrapWriter struct {
@@ -56,6 +57,7 @@ func NewOperation(t *Terminal, cfg *Config) *Operation {
 		outchan:   make(chan []rune),
 		opHistory: newOpHistory(cfg.HistoryFile),
 	}
+	op.opVim = newVimMode(op)
 	op.w = op.buf.w
 	op.opSearch = newOpSearch(op.buf.w, op.buf, op.opHistory)
 	op.opCompleter = newOpCompleter(op.buf.w, op)
@@ -87,13 +89,20 @@ func (o *Operation) ioloop() {
 			case CharInterrupt:
 				o.t.KickRead()
 				fallthrough
-			case CharCancel:
+			case CharBell:
+				continue
+			}
+		}
+
+		if o.IsEnableVimMode() {
+			r = o.HandleVim(r, o.t.ReadRune)
+			if r == 0 {
 				continue
 			}
 		}
 
 		switch r {
-		case CharCancel:
+		case CharBell:
 			if o.IsSearchMode() {
 				o.ExitSearchMode(true)
 				o.buf.Refresh(nil)
@@ -119,11 +128,11 @@ func (o *Operation) ioloop() {
 		case CharKill:
 			o.buf.Kill()
 			keepInCompleteMode = true
-		case MetaNext:
+		case MetaForward:
 			o.buf.MoveToNextWord()
 		case CharTranspose:
 			o.buf.Transpose()
-		case MetaPrev:
+		case MetaBackward:
 			o.buf.MoveToPrevWord()
 		case MetaDelete:
 			o.buf.DeleteWord()
@@ -132,7 +141,9 @@ func (o *Operation) ioloop() {
 		case CharLineEnd:
 			o.buf.MoveToLineEnd()
 		case CharDelete:
-			o.buf.Delete()
+			if !o.buf.Delete() {
+				o.t.Bell()
+			}
 		case CharBackspace, CharCtrlH:
 			if o.IsSearchMode() {
 				o.SearchBackspace()
@@ -141,6 +152,7 @@ func (o *Operation) ioloop() {
 			}
 
 			if o.buf.Len() == 0 {
+				o.t.Bell()
 				break
 			}
 			o.buf.Backspace()
@@ -167,11 +179,15 @@ func (o *Operation) ioloop() {
 			buf := o.PrevHistory()
 			if buf != nil {
 				o.buf.Set(buf)
+			} else {
+				o.t.Bell()
 			}
 		case CharNext:
 			buf, ok := o.NextHistory()
 			if ok {
 				o.buf.Set(buf)
+			} else {
+				o.t.Bell()
 			}
 		case CharInterrupt:
 			if o.IsSearchMode() {

readline.go

@@ -11,6 +11,7 @@ type Config struct {
 	Prompt       string
 	HistoryFile  string
 	AutoComplete AutoCompleter
+	VimMode      bool
 	Stdout       io.Writer
 	Stderr       io.Writer
 
@@ -59,6 +60,14 @@ func (i *Instance) Stderr() io.Writer {
 	return i.o.Stderr()
 }
 
+func (i *Instance) SetVimMode(on bool) {
+	i.o.SetVimMode(on)
+}
+
+func (i *Instance) IsVimMode() bool {
+	return i.o.IsEnableVimMode()
+}
+
 func (i *Instance) ReadPassword(prompt string) ([]byte, error) {
 	return i.o.Password(prompt)
 }

runebuf.go

@@ -5,6 +5,11 @@ import (
 	"io"
 )
 
+type runeBufferBck struct {
+	buf []rune
+	idx int
+}
+
 type RuneBuffer struct {
 	buf    []rune
 	idx    int
@@ -12,6 +17,22 @@ type RuneBuffer struct {
 	w      io.Writer
 
 	cleanInScreen bool
+
+	bck *runeBufferBck
+}
+
+func (r *RuneBuffer) Backup() {
+	r.bck = &runeBufferBck{r.buf, r.idx}
+}
+
+func (r *RuneBuffer) Restore() {
+	r.Refresh(func() {
+		if r.bck == nil {
+			return
+		}
+		r.buf = r.bck.buf
+		r.idx = r.bck.idx
+	})
 }
 
 func NewRuneBuffer(w io.Writer, prompt string) *RuneBuffer {
@@ -98,13 +119,22 @@ func (r *RuneBuffer) MoveForward() {
 	})
 }
 
-func (r *RuneBuffer) Delete() {
+func (r *RuneBuffer) Erase() {
+	r.Refresh(func() {
+		r.idx = 0
+		r.buf = r.buf[:0]
+	})
+}
+
+func (r *RuneBuffer) Delete() (success bool) {
 	r.Refresh(func() {
 		if r.idx == len(r.buf) {
 			return
 		}
 		r.buf = append(r.buf[:r.idx], r.buf[r.idx+1:]...)
+		success = true
 	})
+	return
 }
 
 func (r *RuneBuffer) DeleteWord() {
@@ -126,7 +156,7 @@ func (r *RuneBuffer) DeleteWord() {
 	r.Kill()
 }
 
-func (r *RuneBuffer) MoveToPrevWord() {
+func (r *RuneBuffer) MoveToPrevWord() (success bool) {
 	r.Refresh(func() {
 		if r.idx == 0 {
 			return
@@ -135,11 +165,14 @@ func (r *RuneBuffer) MoveToPrevWord() {
 		for i := r.idx - 1; i > 0; i-- {
 			if !IsWordBreak(r.buf[i]) && IsWordBreak(r.buf[i-1]) {
 				r.idx = i
+				success = true
 				return
 			}
 		}
 		r.idx = 0
+		success = true
 	})
+	return
 }
 
 func (r *RuneBuffer) KillFront() {
@@ -237,6 +270,35 @@ func (r *RuneBuffer) LineCount() int {
 	return LineCount(RunesWidth(r.buf) + r.PromptLen())
 }
 
+func (r *RuneBuffer) MoveTo(ch rune, prevChar, reverse bool) (success bool) {
+	r.Refresh(func() {
+		if reverse {
+			for i := r.idx - 1; i >= 0; i-- {
+				if r.buf[i] == ch {
+					r.idx = i
+					if prevChar {
+						r.idx++
+					}
+					success = true
+					return
+				}
+			}
+			return
+		}
+		for i := r.idx + 1; i < len(r.buf); i++ {
+			if r.buf[i] == ch {
+				r.idx = i
+				if prevChar {
+					r.idx--
+				}
+				success = true
+				return
+			}
+		}
+	})
+	return
+}
+
 func (r *RuneBuffer) IdxLine() int {
 	totalWidth := RunesWidth(r.buf[:r.idx]) + r.PromptLen()
 	w := getWidth()

terminal.go

@@ -113,6 +113,10 @@ func (t *Terminal) ioloop() {
 		expectNextChar = true
 		switch r {
 		case CharEsc:
+			if t.cfg.VimMode {
+				t.outchan <- r
+				break
+			}
 			isEscape = true
 		case CharInterrupt, CharEnter, CharCtrlJ:
 			expectNextChar = false
@@ -123,6 +127,10 @@ func (t *Terminal) ioloop() {
 	}
 }
 
+func (t *Terminal) Bell() {
+	fmt.Fprintf(t, "%c", CharBell)
+}
+
 func (t *Terminal) Close() error {
 	if atomic.SwapInt64(&t.closed, 1) != 0 {
 		return nil

utils.go

@@ -57,9 +57,9 @@ func escapeExKey(r rune) rune {
 func escapeKey(r rune) rune {
 	switch r {
 	case 'b':
-		r = MetaPrev
+		r = MetaBackward
 	case 'f':
-		r = MetaNext
+		r = MetaForward
 	case 'd':
 		r = MetaDelete
 	case CharTranspose:

vim.go

@@ -0,0 +1,149 @@
+package readline
+
+const (
+	VIM_NORMAL = iota
+	VIM_INSERT
+	VIM_VISUAL
+)
+
+type opVim struct {
+	cfg     *Config
+	op      *Operation
+	vimMode int
+}
+
+func newVimMode(op *Operation) *opVim {
+	ov := &opVim{
+		cfg: op.cfg,
+		op:  op,
+	}
+	ov.SetVimMode(ov.cfg.VimMode)
+	return ov
+}
+
+func (o *opVim) SetVimMode(on bool) {
+	if o.cfg.VimMode && !on { // turn off
+		o.ExitVimMode()
+	}
+	o.cfg.VimMode = on
+	o.vimMode = VIM_INSERT
+}
+
+func (o *opVim) ExitVimMode() {
+	o.vimMode = VIM_INSERT
+}
+
+func (o *opVim) IsEnableVimMode() bool {
+	return o.cfg.VimMode
+}
+
+func (o *opVim) handleVimNormalMovement(r rune, readNext func() rune) (t rune, handled bool) {
+	rb := o.op.buf
+	handled = true
+	switch r {
+	case 'h':
+		t = CharBackward
+	case 'j':
+		t = CharNext
+	case 'k':
+		t = CharPrev
+	case 'l':
+		t = CharForward
+	case '0', '^':
+		rb.MoveToLineStart()
+	case '$':
+		rb.MoveToLineEnd()
+	case 'b', 'B':
+		rb.MoveToPrevWord()
+	case 'w', 'W', 'e', 'E':
+		rb.MoveToNextWord()
+	case 'f', 'F', 't', 'T':
+		next := readNext()
+		prevChar := r == 't' || r == 'T'
+		reverse := r == 'F' || r == 'T'
+		switch next {
+		case CharEsc:
+		default:
+			rb.MoveTo(next, prevChar, reverse)
+		}
+	default:
+		return r, false
+	}
+	return t, true
+}
+
+func (o *opVim) handleVimNormalEnterInsert(r rune, readNext func() rune) (t rune, handled bool) {
+	rb := o.op.buf
+	handled = true
+	switch r {
+	case 'i':
+	case 'I':
+		rb.MoveToLineStart()
+	case 'a':
+		rb.MoveForward()
+	case 'A':
+		rb.MoveToLineEnd()
+	case 's':
+		rb.Delete()
+	case 'S':
+		rb.Erase()
+	case 'c':
+		next := readNext()
+		switch next {
+		case 'c':
+			rb.Erase()
+		case 'w':
+			rb.DeleteWord()
+		}
+	default:
+		return r, false
+	}
+
+	o.EnterVimInsertMode()
+	return
+}
+
+func (o *opVim) HandleVimNormal(r rune, readNext func() rune) (t rune) {
+	switch r {
+	case CharEnter, CharInterrupt:
+		o.ExitVimMode()
+		return r
+	}
+
+	if r, handled := o.handleVimNormalMovement(r, readNext); handled {
+		return r
+	}
+
+	if r, handled := o.handleVimNormalEnterInsert(r, readNext); handled {
+		return r
+	}
+
+	// invalid operation
+	o.op.t.Bell()
+	return 0
+}
+
+func (o *opVim) EnterVimInsertMode() {
+	o.vimMode = VIM_INSERT
+}
+
+func (o *opVim) ExitVimInsertMode() {
+	o.vimMode = VIM_NORMAL
+}
+
+func (o *opVim) HandleVim(r rune, readNext func() rune) rune {
+	if o.vimMode == VIM_NORMAL {
+		return o.HandleVimNormal(r, readNext)
+	}
+	if r == CharEsc {
+		o.ExitVimInsertMode()
+		return 0
+	}
+
+	switch o.vimMode {
+	case VIM_INSERT:
+		return r
+	case VIM_VISUAL:
+	}
+	return r
+}