0.13.4

Approx. 50% less memory footprint and 40% improvement in query time

CHANGELOG.md

@@ -1,6 +1,14 @@
 CHANGELOG
 =========
 
+0.13.4
+------
+- Performance optimization
+    - Memory footprint for ascii string is reduced by 60%
+    - 15 to 20% improvement of query performance
+    - Up to 45% better performance of `--nth` with non-regex delimiters
+- Fixed invalid handling of `hidden` property of `--preview-window`
+
 0.13.3
 ------
 - Fixed duplicate rendering of the last line in preview window

README.md

@@ -320,10 +320,10 @@ customization.
 
 [fzf-config]: https://github.com/junegunn/fzf/wiki/Configuring-FZF-command-(vim)
 
-#### `fzf#run([options])`
+#### `fzf#run`
 
-For more advanced uses, you can use `fzf#run()` function with the following
-options.
+For more advanced uses, you can use `fzf#run([options])` function with the
+following options.
 
 | Option name                | Type          | Description                                                      |
 | -------------------------- | ------------- | ---------------------------------------------------------------- |
@@ -342,6 +342,17 @@ options.
 Examples can be found on [the wiki
 page](https://github.com/junegunn/fzf/wiki/Examples-(vim)).
 
+#### `fzf#wrap`
+
+`fzf#wrap(name string, [opts dict, [fullscreen boolean]])` is a helper
+function that decorates the options dictionary so that it understands
+`g:fzf_layout`, `g:fzf_action`, and `g:fzf_history_dir` like `:FZF`.
+
+```vim
+command! -bang MyStuff
+  \ call fzf#run(fzf#wrap('my-stuff', {'dir': '~/my-stuff'}, <bang>0))
+```
+
 Tips
 ----
 

install

@@ -2,8 +2,8 @@
 
 set -u
 
-[[ "$@" =~ --pre ]] && version=0.13.3 pre=1 ||
-                       version=0.13.3 pre=0
+[[ "$@" =~ --pre ]] && version=0.13.4 pre=1 ||
+                       version=0.13.4 pre=0
 
 auto_completion=
 key_bindings=

man/man1/fzf-tmux.1

@@ -21,7 +21,7 @@ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 ..
-.TH fzf-tmux 1 "Jul 2016" "fzf 0.13.3" "fzf-tmux - open fzf in tmux split pane"
+.TH fzf-tmux 1 "Aug 2016" "fzf 0.13.4" "fzf-tmux - open fzf in tmux split pane"
 
 .SH NAME
 fzf-tmux - open fzf in tmux split pane

man/man1/fzf.1

@@ -21,7 +21,7 @@ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 ..
-.TH fzf 1 "Jul 2016" "fzf 0.13.3" "fzf - a command-line fuzzy finder"
+.TH fzf 1 "Aug 2016" "fzf 0.13.4" "fzf - a command-line fuzzy finder"
 
 .SH NAME
 fzf - a command-line fuzzy finder

plugin/fzf.vim

@@ -21,7 +21,8 @@
 " OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 " WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-let s:default_height = '40%'
+let s:default_layout = { 'down': '~40%' }
+let s:layout_keys = ['window', 'up', 'down', 'left', 'right']
 let s:fzf_go = expand('<sfile>:h:h').'/bin/fzf'
 let s:install = expand('<sfile>:h:h').'/install'
 let s:installed = 0
@@ -104,11 +105,106 @@ function! s:warn(msg)
   echohl None
 endfunction
 
+function! s:has_any(dict, keys)
+  for key in a:keys
+    if has_key(a:dict, key)
+      return 1
+    endif
+  endfor
+  return 0
+endfunction
+
+function! s:open(cmd, target)
+  if stridx('edit', a:cmd) == 0 && fnamemodify(a:target, ':p') ==# expand('%:p')
+    return
+  endif
+  execute a:cmd s:escape(a:target)
+endfunction
+
+function! s:common_sink(action, lines) abort
+  if len(a:lines) < 2
+    return
+  endif
+  let key = remove(a:lines, 0)
+  let cmd = get(a:action, key, 'e')
+  if len(a:lines) > 1
+    augroup fzf_swap
+      autocmd SwapExists * let v:swapchoice='o'
+            \| call s:warn('fzf: E325: swap file exists: '.expand('<afile>'))
+    augroup END
+  endif
+  try
+    let empty = empty(expand('%')) && line('$') == 1 && empty(getline(1)) && !&modified
+    let autochdir = &autochdir
+    set noautochdir
+    for item in a:lines
+      if empty
+        execute 'e' s:escape(item)
+        let empty = 0
+      else
+        call s:open(cmd, item)
+      endif
+      if exists('#BufEnter') && isdirectory(item)
+        doautocmd BufEnter
+      endif
+    endfor
+  finally
+    let &autochdir = autochdir
+    silent! autocmd! fzf_swap
+  endtry
+endfunction
+
+" name string, [opts dict, [fullscreen boolean]]
+function! fzf#wrap(name, ...)
+  if type(a:name) != type('')
+    throw 'invalid name type: string expected'
+  endif
+  let opts = copy(get(a:000, 0, {}))
+  let bang = get(a:000, 1, 0)
+
+  " Layout: g:fzf_layout (and deprecated g:fzf_height)
+  if bang
+    for key in s:layout_keys
+      if has_key(opts, key)
+        call remove(opts, key)
+      endif
+    endfor
+  elseif !s:has_any(opts, s:layout_keys)
+    if !exists('g:fzf_layout') && exists('g:fzf_height')
+      let opts.down = g:fzf_height
+    else
+      let opts = extend(opts, get(g:, 'fzf_layout', s:default_layout))
+    endif
+  endif
+
+  " History: g:fzf_history_dir
+  let opts.options = get(opts, 'options', '')
+  if len(get(g:, 'fzf_history_dir', ''))
+    let dir = expand(g:fzf_history_dir)
+    if !isdirectory(dir)
+      call mkdir(dir, 'p')
+    endif
+    let opts.options = join(['--history', s:escape(dir.'/'.a:name), opts.options])
+  endif
+
+  " Action: g:fzf_action
+  if !s:has_any(opts, ['sink', 'sink*'])
+    let opts._action = get(g:, 'fzf_action', s:default_action)
+    let opts.options .= ' --expect='.join(keys(opts._action), ',')
+    function! opts.sink(lines) abort
+      return s:common_sink(self._action, a:lines)
+    endfunction
+    let opts['sink*'] = remove(opts, 'sink')
+  endif
+
+  return opts
+endfunction
+
 function! fzf#run(...) abort
 try
   let oshell = &shell
   set shell=sh
-  if has('nvim') && bufexists('term://*:FZF')
+  if has('nvim') && len(filter(range(1, bufnr('$')), 'bufname(v:val) =~# ";#FZF"'))
     call s:warn('FZF is already running!')
     return []
   endif
@@ -137,7 +233,7 @@ try
       call writefile(source, temps.input)
       let prefix = 'cat '.s:shellesc(temps.input).'|'
     else
-      throw 'Invalid source type'
+      throw 'invalid source type'
     endif
   else
     let prefix = ''
@@ -252,8 +348,9 @@ function! s:execute(dict, command, temps) abort
     let command = escaped
   endif
   execute 'silent !'.command
+  let exit_status = v:shell_error
   redraw!
-  return s:exit_handler(v:shell_error, command) ? s:collect(a:temps) : []
+  return s:exit_handler(exit_status, command) ? s:collect(a:temps) : []
 endfunction
 
 function! s:execute_tmux(dict, command, temps) abort
@@ -264,8 +361,9 @@ function! s:execute_tmux(dict, command, temps) abort
   endif
 
   call system(command)
+  let exit_status = v:shell_error
   redraw!
-  return s:exit_handler(v:shell_error, command) ? s:collect(a:temps) : []
+  return s:exit_handler(exit_status, command) ? s:collect(a:temps) : []
 endfunction
 
 function! s:calc_size(max, val, dict)
@@ -326,7 +424,7 @@ endfunction
 function! s:execute_term(dict, command, temps) abort
   let [ppos, winopts] = s:split(a:dict)
   let fzf = { 'buf': bufnr('%'), 'ppos': ppos, 'dict': a:dict, 'temps': a:temps,
-            \ 'name': 'FZF', 'winopts': winopts, 'command': a:command }
+            \ 'winopts': winopts, 'command': a:command }
   function! fzf.switch_back(inplace)
     if a:inplace && bufnr('') == self.buf
       " FIXME: Can't re-enter normal mode from terminal mode
@@ -354,6 +452,10 @@ function! s:execute_term(dict, command, temps) abort
       execute self.ppos.win.'wincmd w'
     endif
 
+    if bufexists(self.buf)
+      execute 'bd!' self.buf
+    endif
+
     if !s:exit_handler(a:code, self.command, 1)
       return
     endif
@@ -368,7 +470,7 @@ function! s:execute_term(dict, command, temps) abort
     if s:present(a:dict, 'dir')
       execute 'lcd' s:escape(a:dict.dir)
     endif
-    call termopen(a:command, fzf)
+    call termopen(a:command . ';#FZF', fzf)
   finally
     if s:present(a:dict, 'dir')
       lcd -
@@ -435,59 +537,20 @@ function! s:callback(dict, lines) abort
 endfunction
 
 let s:default_action = {
-  \ 'ctrl-m': 'e',
   \ 'ctrl-t': 'tab split',
   \ 'ctrl-x': 'split',
   \ 'ctrl-v': 'vsplit' }
 
-function! s:cmd_callback(lines) abort
-  if empty(a:lines)
-    return
-  endif
-  let key = remove(a:lines, 0)
-  let cmd = get(s:action, key, 'e')
-  if len(a:lines) > 1
-    augroup fzf_swap
-      autocmd SwapExists * let v:swapchoice='o'
-            \| call s:warn('fzf: E325: swap file exists: '.expand('<afile>'))
-    augroup END
-  endif
-  try
-    let empty = empty(expand('%')) && line('$') == 1 && empty(getline(1)) && !&modified
-    let autochdir = &autochdir
-    set noautochdir
-    for item in a:lines
-      if empty
-        execute 'e' s:escape(item)
-        let empty = 0
-      else
-        execute cmd s:escape(item)
-      endif
-      if exists('#BufEnter') && isdirectory(item)
-        doautocmd BufEnter
-      endif
-    endfor
-  finally
-    let &autochdir = autochdir
-    silent! autocmd! fzf_swap
-  endtry
-endfunction
-
 function! s:cmd(bang, ...) abort
-  let s:action = get(g:, 'fzf_action', s:default_action)
-  let args = extend(['--expect='.join(keys(s:action), ',')], a:000)
+  let args = copy(a:000)
   let opts = {}
-  if len(args) > 0 && isdirectory(expand(args[-1]))
+  if len(args) && isdirectory(expand(args[-1]))
     let opts.dir = substitute(remove(args, -1), '\\\(["'']\)', '\1', 'g')
   endif
-  if !a:bang
-    let opts.down = get(g:, 'fzf_height', get(g:, 'fzf_tmux_height', s:default_height))
-  endif
-  call fzf#run(extend({'options': join(args), 'sink*': function('<sid>cmd_callback')}, opts))
+  call fzf#run(fzf#wrap('FZF', extend({'options': join(args)}, opts), a:bang))
 endfunction
 
 command! -nargs=* -complete=dir -bang FZF call s:cmd(<bang>0, <f-args>)
 
 let &cpo = s:cpo_save
 unlet s:cpo_save
-

src/algo/algo.go

@@ -15,11 +15,18 @@ import (
  * In short: They try to do as little work as possible.
  */
 
-func runeAt(runes []rune, index int, max int, forward bool) rune {
+func indexAt(index int, max int, forward bool) int {
 	if forward {
-		return runes[index]
+		return index
 	}
-	return runes[max-index-1]
+	return max - index - 1
+}
+
+func runeAt(text util.Chars, index int, max int, forward bool) rune {
+	if forward {
+		return text.Get(index)
+	}
+	return text.Get(max - index - 1)
 }
 
 // Result conatins the results of running a match function.
@@ -42,14 +49,14 @@ const (
 	charNumber
 )
 
-func evaluateBonus(caseSensitive bool, runes []rune, pattern []rune, sidx int, eidx int) int32 {
+func evaluateBonus(caseSensitive bool, text util.Chars, pattern []rune, sidx int, eidx int) int32 {
 	var bonus int32
 	pidx := 0
 	lenPattern := len(pattern)
 	consecutive := false
 	prevClass := charNonWord
-	for index := 0; index < eidx; index++ {
-		char := runes[index]
+	for index := util.Max(0, sidx-1); index < eidx; index++ {
+		char := text.Get(index)
 		var class charClass
 		if unicode.IsLower(char) {
 			class = charLower
@@ -107,7 +114,7 @@ func evaluateBonus(caseSensitive bool, runes []rune, pattern []rune, sidx int, e
 }
 
 // FuzzyMatch performs fuzzy-match
-func FuzzyMatch(caseSensitive bool, forward bool, runes []rune, pattern []rune) Result {
+func FuzzyMatch(caseSensitive bool, forward bool, text util.Chars, pattern []rune) Result {
 	if len(pattern) == 0 {
 		return Result{0, 0, 0}
 	}
@@ -125,11 +132,11 @@ func FuzzyMatch(caseSensitive bool, forward bool, runes []rune, pattern []rune)
 	sidx := -1
 	eidx := -1
 
-	lenRunes := len(runes)
+	lenRunes := text.Length()
 	lenPattern := len(pattern)
 
-	for index := range runes {
-		char := runeAt(runes, index, lenRunes, forward)
+	for index := 0; index < lenRunes; index++ {
+		char := runeAt(text, index, lenRunes, forward)
 		// This is considerably faster than blindly applying strings.ToLower to the
 		// whole string
 		if !caseSensitive {
@@ -142,7 +149,7 @@ func FuzzyMatch(caseSensitive bool, forward bool, runes []rune, pattern []rune)
 				char = unicode.To(unicode.LowerCase, char)
 			}
 		}
-		pchar := runeAt(pattern, pidx, lenPattern, forward)
+		pchar := pattern[indexAt(pidx, lenPattern, forward)]
 		if char == pchar {
 			if sidx < 0 {
 				sidx = index
@@ -157,7 +164,7 @@ func FuzzyMatch(caseSensitive bool, forward bool, runes []rune, pattern []rune)
 	if sidx >= 0 && eidx >= 0 {
 		pidx--
 		for index := eidx - 1; index >= sidx; index-- {
-			char := runeAt(runes, index, lenRunes, forward)
+			char := runeAt(text, index, lenRunes, forward)
 			if !caseSensitive {
 				if char >= 'A' && char <= 'Z' {
 					char += 32
@@ -166,7 +173,7 @@ func FuzzyMatch(caseSensitive bool, forward bool, runes []rune, pattern []rune)
 				}
 			}
 
-			pchar := runeAt(pattern, pidx, lenPattern, forward)
+			pchar := pattern[indexAt(pidx, lenPattern, forward)]
 			if char == pchar {
 				if pidx--; pidx < 0 {
 					sidx = index
@@ -182,7 +189,7 @@ func FuzzyMatch(caseSensitive bool, forward bool, runes []rune, pattern []rune)
 		}
 
 		return Result{int32(sidx), int32(eidx),
-			evaluateBonus(caseSensitive, runes, pattern, sidx, eidx)}
+			evaluateBonus(caseSensitive, text, pattern, sidx, eidx)}
 	}
 	return Result{-1, -1, 0}
 }
@@ -194,12 +201,12 @@ func FuzzyMatch(caseSensitive bool, forward bool, runes []rune, pattern []rune)
 //
 // We might try to implement better algorithms in the future:
 // http://en.wikipedia.org/wiki/String_searching_algorithm
-func ExactMatchNaive(caseSensitive bool, forward bool, runes []rune, pattern []rune) Result {
+func ExactMatchNaive(caseSensitive bool, forward bool, text util.Chars, pattern []rune) Result {
 	if len(pattern) == 0 {
 		return Result{0, 0, 0}
 	}
 
-	lenRunes := len(runes)
+	lenRunes := text.Length()
 	lenPattern := len(pattern)
 
 	if lenRunes < lenPattern {
@@ -208,7 +215,7 @@ func ExactMatchNaive(caseSensitive bool, forward bool, runes []rune, pattern []r
 
 	pidx := 0
 	for index := 0; index < lenRunes; index++ {
-		char := runeAt(runes, index, lenRunes, forward)
+		char := runeAt(text, index, lenRunes, forward)
 		if !caseSensitive {
 			if char >= 'A' && char <= 'Z' {
 				char += 32
@@ -216,7 +223,7 @@ func ExactMatchNaive(caseSensitive bool, forward bool, runes []rune, pattern []r
 				char = unicode.To(unicode.LowerCase, char)
 			}
 		}
-		pchar := runeAt(pattern, pidx, lenPattern, forward)
+		pchar := pattern[indexAt(pidx, lenPattern, forward)]
 		if pchar == char {
 			pidx++
 			if pidx == lenPattern {
@@ -229,7 +236,7 @@ func ExactMatchNaive(caseSensitive bool, forward bool, runes []rune, pattern []r
 					eidx = lenRunes - (index - lenPattern + 1)
 				}
 				return Result{int32(sidx), int32(eidx),
-					evaluateBonus(caseSensitive, runes, pattern, sidx, eidx)}
+					evaluateBonus(caseSensitive, text, pattern, sidx, eidx)}
 			}
 		} else {
 			index -= pidx
@@ -240,13 +247,13 @@ func ExactMatchNaive(caseSensitive bool, forward bool, runes []rune, pattern []r
 }
 
 // PrefixMatch performs prefix-match
-func PrefixMatch(caseSensitive bool, forward bool, runes []rune, pattern []rune) Result {
-	if len(runes) < len(pattern) {
+func PrefixMatch(caseSensitive bool, forward bool, text util.Chars, pattern []rune) Result {
+	if text.Length() < len(pattern) {
 		return Result{-1, -1, 0}
 	}
 
 	for index, r := range pattern {
-		char := runes[index]
+		char := text.Get(index)
 		if !caseSensitive {
 			char = unicode.ToLower(char)
 		}
@@ -256,20 +263,19 @@ func PrefixMatch(caseSensitive bool, forward bool, runes []rune, pattern []rune)
 	}
 	lenPattern := len(pattern)
 	return Result{0, int32(lenPattern),
-		evaluateBonus(caseSensitive, runes, pattern, 0, lenPattern)}
+		evaluateBonus(caseSensitive, text, pattern, 0, lenPattern)}
 }
 
 // SuffixMatch performs suffix-match
-func SuffixMatch(caseSensitive bool, forward bool, input []rune, pattern []rune) Result {
-	runes := util.TrimRight(input)
-	trimmedLen := len(runes)
+func SuffixMatch(caseSensitive bool, forward bool, text util.Chars, pattern []rune) Result {
+	trimmedLen := text.Length() - text.TrailingWhitespaces()
 	diff := trimmedLen - len(pattern)
 	if diff < 0 {
 		return Result{-1, -1, 0}
 	}
 
 	for index, r := range pattern {
-		char := runes[index+diff]
+		char := text.Get(index + diff)
 		if !caseSensitive {
 			char = unicode.ToLower(char)
 		}
@@ -281,16 +287,16 @@ func SuffixMatch(caseSensitive bool, forward bool, input []rune, pattern []rune)
 	sidx := trimmedLen - lenPattern
 	eidx := trimmedLen
 	return Result{int32(sidx), int32(eidx),
-		evaluateBonus(caseSensitive, runes, pattern, sidx, eidx)}
+		evaluateBonus(caseSensitive, text, pattern, sidx, eidx)}
 }
 
 // EqualMatch performs equal-match
-func EqualMatch(caseSensitive bool, forward bool, runes []rune, pattern []rune) Result {
+func EqualMatch(caseSensitive bool, forward bool, text util.Chars, pattern []rune) Result {
 	// Note: EqualMatch always return a zero bonus.
-	if len(runes) != len(pattern) {
+	if text.Length() != len(pattern) {
 		return Result{-1, -1, 0}
 	}
-	runesStr := string(runes)
+	runesStr := text.ToString()
 	if !caseSensitive {
 		runesStr = strings.ToLower(runesStr)
 	}

src/algo/algo_test.go

@@ -3,13 +3,15 @@ package algo
 import (
 	"strings"
 	"testing"
+
+	"github.com/junegunn/fzf/src/util"
 )
 
-func assertMatch(t *testing.T, fun func(bool, bool, []rune, []rune) Result, caseSensitive, forward bool, input, pattern string, sidx int32, eidx int32, bonus int32) {
+func assertMatch(t *testing.T, fun func(bool, bool, util.Chars, []rune) Result, caseSensitive, forward bool, input, pattern string, sidx int32, eidx int32, bonus int32) {
 	if !caseSensitive {
 		pattern = strings.ToLower(pattern)
 	}
-	res := fun(caseSensitive, forward, []rune(input), []rune(pattern))
+	res := fun(caseSensitive, forward, util.RunesToChars([]rune(input)), []rune(pattern))
 	if res.Start != sidx {
 		t.Errorf("Invalid start index: %d (expected: %d, %s / %s)", res.Start, sidx, input, pattern)
 	}

src/chunklist_test.go

@@ -3,6 +3,8 @@ package fzf
 import (
 	"fmt"
 	"testing"
+
+	"github.com/junegunn/fzf/src/util"
 )
 
 func TestChunkList(t *testing.T) {
@@ -10,7 +12,7 @@ func TestChunkList(t *testing.T) {
 	sortCriteria = []criterion{byMatchLen, byLength}
 
 	cl := NewChunkList(func(s []byte, i int) *Item {
-		return &Item{text: []rune(string(s)), rank: buildEmptyRank(int32(i * 2))}
+		return &Item{text: util.ToChars(s), rank: buildEmptyRank(int32(i * 2))}
 	})
 
 	// Snapshot
@@ -42,8 +44,8 @@ func TestChunkList(t *testing.T) {
 	last := func(arr [5]int32) int32 {
 		return arr[len(arr)-1]
 	}
-	if string((*chunk1)[0].text) != "hello" || last((*chunk1)[0].rank) != 0 ||
-		string((*chunk1)[1].text) != "world" || last((*chunk1)[1].rank) != 2 {
+	if (*chunk1)[0].text.ToString() != "hello" || last((*chunk1)[0].rank) != 0 ||
+		(*chunk1)[1].text.ToString() != "world" || last((*chunk1)[1].rank) != 2 {
 		t.Error("Invalid data")
 	}
 	if chunk1.IsFull() {

src/constants.go

@@ -8,7 +8,7 @@ import (
 
 const (
 	// Current version
-	version = "0.13.3"
+	version = "0.13.4"
 
 	// Core
 	coordinatorDelayMax  time.Duration = 100 * time.Millisecond

src/core.go

@@ -63,29 +63,29 @@ func Run(opts *Options) {
 	eventBox := util.NewEventBox()
 
 	// ANSI code processor
-	ansiProcessor := func(data []byte) ([]rune, []ansiOffset) {
-		return util.BytesToRunes(data), nil
+	ansiProcessor := func(data []byte) (util.Chars, []ansiOffset) {
+		return util.ToChars(data), nil
 	}
-	ansiProcessorRunes := func(data []rune) ([]rune, []ansiOffset) {
-		return data, nil
+	ansiProcessorRunes := func(data []rune) (util.Chars, []ansiOffset) {
+		return util.RunesToChars(data), nil
 	}
 	if opts.Ansi {
 		if opts.Theme != nil {
 			var state *ansiState
-			ansiProcessor = func(data []byte) ([]rune, []ansiOffset) {
+			ansiProcessor = func(data []byte) (util.Chars, []ansiOffset) {
 				trimmed, offsets, newState := extractColor(string(data), state, nil)
 				state = newState
-				return []rune(trimmed), offsets
+				return util.RunesToChars([]rune(trimmed)), offsets
 			}
 		} else {
 			// When color is disabled but ansi option is given,
 			// we simply strip out ANSI codes from the input
-			ansiProcessor = func(data []byte) ([]rune, []ansiOffset) {
+			ansiProcessor = func(data []byte) (util.Chars, []ansiOffset) {
 				trimmed, _, _ := extractColor(string(data), nil, nil)
-				return []rune(trimmed), nil
+				return util.RunesToChars([]rune(trimmed)), nil
 			}
 		}
-		ansiProcessorRunes = func(data []rune) ([]rune, []ansiOffset) {
+		ansiProcessorRunes = func(data []rune) (util.Chars, []ansiOffset) {
 			return ansiProcessor([]byte(string(data)))
 		}
 	}
@@ -100,29 +100,30 @@ func Run(opts *Options) {
 				eventBox.Set(EvtHeader, header)
 				return nil
 			}
-			runes, colors := ansiProcessor(data)
+			chars, colors := ansiProcessor(data)
 			return &Item{
-				text:   runes,
+				text:   chars,
 				colors: colors,
 				rank:   buildEmptyRank(int32(index))}
 		})
 	} else {
 		chunkList = NewChunkList(func(data []byte, index int) *Item {
-			runes := util.BytesToRunes(data)
-			tokens := Tokenize(runes, opts.Delimiter)
+			chars := util.ToChars(data)
+			tokens := Tokenize(chars, opts.Delimiter)
 			trans := Transform(tokens, opts.WithNth)
 			if len(header) < opts.HeaderLines {
 				header = append(header, string(joinTokens(trans)))
 				eventBox.Set(EvtHeader, header)
 				return nil
 			}
+			textRunes := joinTokens(trans)
 			item := Item{
-				text:     joinTokens(trans),
-				origText: &runes,
+				text:     util.RunesToChars(textRunes),
+				origText: &data,
 				colors:   nil,
 				rank:     buildEmptyRank(int32(index))}
 
-			trimmed, colors := ansiProcessorRunes(item.text)
+			trimmed, colors := ansiProcessorRunes(textRunes)
 			item.text = trimmed
 			item.colors = colors
 			return &item
@@ -170,7 +171,7 @@ func Run(opts *Options) {
 				func(runes []byte) bool {
 					item := chunkList.trans(runes, 0)
 					if item != nil && pattern.MatchItem(item) {
-						fmt.Println(string(item.text))
+						fmt.Println(item.text.ToString())
 						found = true
 					}
 					return false

src/item.go

@@ -4,6 +4,7 @@ import (
 	"math"
 
 	"github.com/junegunn/fzf/src/curses"
+	"github.com/junegunn/fzf/src/util"
 )
 
 // Offset holds three 32-bit integers denoting the offsets of a matched substring
@@ -17,8 +18,8 @@ type colorOffset struct {
 
 // Item represents each input line
 type Item struct {
-	text        []rune
-	origText    *[]rune
+	text        util.Chars
+	origText    *[]byte
 	transformed []Token
 	offsets     []Offset
 	colors      []ansiOffset
@@ -43,6 +44,7 @@ func buildEmptyRank(index int32) [5]int32 {
 	return [5]int32{0, 0, 0, 0, index}
 }
 
+// Index returns ordinal index of the Item
 func (item *Item) Index() int32 {
 	return item.rank[4]
 }
@@ -91,12 +93,14 @@ func (item *Item) Rank(cache bool) [5]int32 {
 				// If offsets is empty, lenSum will be 0, but we don't care
 				val = int32(lenSum)
 			} else {
-				val = int32(len(item.text))
+				val = int32(item.text.Length())
 			}
 		case byBegin:
 			// We can't just look at item.offsets[0][0] because it can be an inverse term
 			whitePrefixLen := 0
-			for idx, r := range item.text {
+			numChars := item.text.Length()
+			for idx := 0; idx < numChars; idx++ {
+				r := item.text.Get(idx)
 				whitePrefixLen = idx
 				if idx == minBegin || r != ' ' && r != '\t' {
 					break
@@ -105,7 +109,7 @@ func (item *Item) Rank(cache bool) [5]int32 {
 			val = int32(minBegin - whitePrefixLen)
 		case byEnd:
 			if prevEnd > 0 {
-				val = int32(1 + len(item.text) - prevEnd)
+				val = int32(1 + item.text.Length() - prevEnd)
 			} else {
 				// Empty offsets due to inverse terms.
 				val = 1
@@ -134,7 +138,7 @@ func (item *Item) StringPtr(stripAnsi bool) *string {
 		orig := string(*item.origText)
 		return &orig
 	}
-	str := string(item.text)
+	str := item.text.ToString()
 	return &str
 }
 

src/item_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 
 	"github.com/junegunn/fzf/src/curses"
+	"github.com/junegunn/fzf/src/util"
 )
 
 func TestOffsetSort(t *testing.T) {
@@ -44,13 +45,13 @@ func TestItemRank(t *testing.T) {
 	sortCriteria = []criterion{byMatchLen, byLength}
 
 	strs := [][]rune{[]rune("foo"), []rune("foobar"), []rune("bar"), []rune("baz")}
-	item1 := Item{text: strs[0], offsets: []Offset{}, rank: [5]int32{0, 0, 0, 0, 1}}
+	item1 := Item{text: util.RunesToChars(strs[0]), offsets: []Offset{}, rank: [5]int32{0, 0, 0, 0, 1}}
 	rank1 := item1.Rank(true)
 	if rank1[0] != math.MaxInt32 || rank1[1] != 3 || rank1[4] != 1 {
 		t.Error(item1.Rank(true))
 	}
 	// Only differ in index
-	item2 := Item{text: strs[0], offsets: []Offset{}}
+	item2 := Item{text: util.RunesToChars(strs[0]), offsets: []Offset{}}
 
 	items := []*Item{&item1, &item2}
 	sort.Sort(ByRelevance(items))
@@ -66,10 +67,10 @@ func TestItemRank(t *testing.T) {
 	}
 
 	// Sort by relevance
-	item3 := Item{text: strs[1], rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 3}, Offset{5, 7}}}
-	item4 := Item{text: strs[1], rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 2}, Offset{6, 7}}}
-	item5 := Item{text: strs[2], rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 3}, Offset{5, 7}}}
-	item6 := Item{text: strs[2], rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 2}, Offset{6, 7}}}
+	item3 := Item{text: util.RunesToChars(strs[1]), rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 3}, Offset{5, 7}}}
+	item4 := Item{text: util.RunesToChars(strs[1]), rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 2}, Offset{6, 7}}}
+	item5 := Item{text: util.RunesToChars(strs[2]), rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 3}, Offset{5, 7}}}
+	item6 := Item{text: util.RunesToChars(strs[2]), rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 2}, Offset{6, 7}}}
 	items = []*Item{&item1, &item2, &item3, &item4, &item5, &item6}
 	sort.Sort(ByRelevance(items))
 	if items[0] != &item6 || items[1] != &item4 ||

src/matcher.go

@@ -200,7 +200,7 @@ func (m *Matcher) scan(request MatchRequest) (*Merger, bool) {
 	}
 
 	partialResults := make([][]*Item, numSlices)
-	for _, _ = range slices {
+	for _ = range slices {
 		partialResult := <-resultChan
 		partialResults[partialResult.index] = partialResult.matches
 	}

src/merger.go

@@ -2,7 +2,7 @@ package fzf
 
 import "fmt"
 
-// Merger with no data
+// EmptyMerger is a Merger with no data
 var EmptyMerger = NewMerger([][]*Item{}, false, false)
 
 // Merger holds a set of locally sorted lists of items and provides the view of

src/merger_test.go

@@ -5,6 +5,8 @@ import (
 	"math/rand"
 	"sort"
 	"testing"
+
+	"github.com/junegunn/fzf/src/util"
 )
 
 func assert(t *testing.T, cond bool, msg ...string) {
@@ -22,7 +24,7 @@ func randItem() *Item {
 		offsets[idx] = Offset{sidx, eidx}
 	}
 	return &Item{
-		text:    []rune(str),
+		text:    util.RunesToChars([]rune(str)),
 		rank:    buildEmptyRank(rand.Int31()),
 		offsets: offsets}
 }

src/options.go

@@ -724,6 +724,7 @@ func parseSize(str string, maxPercent float64, label string) sizeSpec {
 
 func parsePreviewWindow(opts *previewOpts, input string) {
 	layout := input
+	opts.hidden = false
 	if strings.HasSuffix(layout, ":hidden") {
 		opts.hidden = true
 		layout = strings.TrimSuffix(layout, ":hidden")

src/options_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 
 	"github.com/junegunn/fzf/src/curses"
+	"github.com/junegunn/fzf/src/util"
 )
 
 func TestDelimiterRegex(t *testing.T) {
@@ -42,24 +43,24 @@ func TestDelimiterRegex(t *testing.T) {
 
 func TestDelimiterRegexString(t *testing.T) {
 	delim := delimiterRegexp("*")
-	tokens := Tokenize([]rune("-*--*---**---"), delim)
+	tokens := Tokenize(util.RunesToChars([]rune("-*--*---**---")), delim)
 	if delim.regex != nil ||
-		string(tokens[0].text) != "-*" ||
-		string(tokens[1].text) != "--*" ||
-		string(tokens[2].text) != "---*" ||
-		string(tokens[3].text) != "*" ||
-		string(tokens[4].text) != "---" {
+		tokens[0].text.ToString() != "-*" ||
+		tokens[1].text.ToString() != "--*" ||
+		tokens[2].text.ToString() != "---*" ||
+		tokens[3].text.ToString() != "*" ||
+		tokens[4].text.ToString() != "---" {
 		t.Errorf("%s %s %d", delim, tokens, len(tokens))
 	}
 }
 
 func TestDelimiterRegexRegex(t *testing.T) {
 	delim := delimiterRegexp("--\\*")
-	tokens := Tokenize([]rune("-*--*---**---"), delim)
+	tokens := Tokenize(util.RunesToChars([]rune("-*--*---**---")), delim)
 	if delim.str != nil ||
-		string(tokens[0].text) != "-*--*" ||
-		string(tokens[1].text) != "---*" ||
-		string(tokens[2].text) != "*---" {
+		tokens[0].text.ToString() != "-*--*" ||
+		tokens[1].text.ToString() != "---*" ||
+		tokens[2].text.ToString() != "*---" {
 		t.Errorf("%s %d", tokens, len(tokens))
 	}
 }
@@ -352,14 +353,14 @@ func TestDefaultCtrlNP(t *testing.T) {
 	check([]string{hist, "--bind=ctrl-p:accept"}, curses.CtrlP, actAccept)
 }
 
-func TestToggle(t *testing.T) {
-	optsFor := func(words ...string) *Options {
-		opts := defaultOptions()
-		parseOptions(opts, words)
-		postProcessOptions(opts)
-		return opts
-	}
+func optsFor(words ...string) *Options {
+	opts := defaultOptions()
+	parseOptions(opts, words)
+	postProcessOptions(opts)
+	return opts
+}
 
+func TestToggle(t *testing.T) {
 	opts := optsFor()
 	if opts.ToggleSort {
 		t.Error()
@@ -375,3 +376,31 @@ func TestToggle(t *testing.T) {
 		t.Error()
 	}
 }
+
+func TestPreviewOpts(t *testing.T) {
+	opts := optsFor()
+	if !(opts.Preview.command == "" &&
+		opts.Preview.hidden == false &&
+		opts.Preview.position == posRight &&
+		opts.Preview.size.percent == true &&
+		opts.Preview.size.size == 50) {
+		t.Error()
+	}
+	opts = optsFor("--preview", "cat {}", "--preview-window=left:15:hidden")
+	if !(opts.Preview.command == "cat {}" &&
+		opts.Preview.hidden == true &&
+		opts.Preview.position == posLeft &&
+		opts.Preview.size.percent == false &&
+		opts.Preview.size.size == 15+2) {
+		t.Error(opts.Preview)
+	}
+
+	opts = optsFor("--preview-window=left:15:hidden", "--preview-window=down")
+	if !(opts.Preview.command == "" &&
+		opts.Preview.hidden == false &&
+		opts.Preview.position == posDown &&
+		opts.Preview.size.percent == true &&
+		opts.Preview.size.size == 50) {
+		t.Error(opts.Preview)
+	}
+}

src/pattern.go

@@ -49,7 +49,7 @@ type Pattern struct {
 	cacheable     bool
 	delimiter     Delimiter
 	nth           []Range
-	procFun       map[termType]func(bool, bool, []rune, []rune) algo.Result
+	procFun       map[termType]func(bool, bool, util.Chars, []rune) algo.Result
 }
 
 var (
@@ -125,7 +125,7 @@ func BuildPattern(fuzzy bool, extended bool, caseMode Case, forward bool,
 		cacheable:     cacheable,
 		nth:           nth,
 		delimiter:     delimiter,
-		procFun:       make(map[termType]func(bool, bool, []rune, []rune) algo.Result)}
+		procFun:       make(map[termType]func(bool, bool, util.Chars, []rune) algo.Result)}
 
 	ptr.procFun[termFuzzy] = algo.FuzzyMatch
 	ptr.procFun[termEqual] = algo.EqualMatch
@@ -361,19 +361,19 @@ func (p *Pattern) prepareInput(item *Item) []Token {
 		tokens := Tokenize(item.text, p.delimiter)
 		ret = Transform(tokens, p.nth)
 	} else {
-		ret = []Token{Token{text: item.text, prefixLength: 0, trimLength: util.TrimLen(item.text)}}
+		ret = []Token{Token{text: item.text, prefixLength: 0, trimLength: item.text.TrimLength()}}
 	}
 	item.transformed = ret
 	return ret
 }
 
-func (p *Pattern) iter(pfun func(bool, bool, []rune, []rune) algo.Result,
+func (p *Pattern) iter(pfun func(bool, bool, util.Chars, []rune) algo.Result,
 	tokens []Token, caseSensitive bool, forward bool, pattern []rune) (Offset, int32) {
 	for _, part := range tokens {
 		prefixLength := int32(part.prefixLength)
 		if res := pfun(caseSensitive, forward, part.text, pattern); res.Start >= 0 {
-			var sidx int32 = res.Start + prefixLength
-			var eidx int32 = res.End + prefixLength
+			sidx := res.Start + prefixLength
+			eidx := res.End + prefixLength
 			return Offset{sidx, eidx, int32(part.trimLength)}, res.Bonus
 		}
 	}

src/pattern_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 
 	"github.com/junegunn/fzf/src/algo"
+	"github.com/junegunn/fzf/src/util"
 )
 
 func TestParseTermsExtended(t *testing.T) {
@@ -71,7 +72,7 @@ func TestExact(t *testing.T) {
 	pattern := BuildPattern(true, true, CaseSmart, true,
 		[]Range{}, Delimiter{}, []rune("'abc"))
 	res := algo.ExactMatchNaive(
-		pattern.caseSensitive, pattern.forward, []rune("aabbcc abc"), pattern.termSets[0][0].text)
+		pattern.caseSensitive, pattern.forward, util.RunesToChars([]rune("aabbcc abc")), pattern.termSets[0][0].text)
 	if res.Start != 7 || res.End != 10 {
 		t.Errorf("%s / %d / %d", pattern.termSets, res.Start, res.End)
 	}
@@ -84,7 +85,7 @@ func TestEqual(t *testing.T) {
 
 	match := func(str string, sidxExpected int32, eidxExpected int32) {
 		res := algo.EqualMatch(
-			pattern.caseSensitive, pattern.forward, []rune(str), pattern.termSets[0][0].text)
+			pattern.caseSensitive, pattern.forward, util.RunesToChars([]rune(str)), pattern.termSets[0][0].text)
 		if res.Start != sidxExpected || res.End != eidxExpected {
 			t.Errorf("%s / %d / %d", pattern.termSets, res.Start, res.End)
 		}
@@ -120,20 +121,20 @@ func TestCaseSensitivity(t *testing.T) {
 
 func TestOrigTextAndTransformed(t *testing.T) {
 	pattern := BuildPattern(true, true, CaseSmart, true, []Range{}, Delimiter{}, []rune("jg"))
-	tokens := Tokenize([]rune("junegunn"), Delimiter{})
+	tokens := Tokenize(util.RunesToChars([]rune("junegunn")), Delimiter{})
 	trans := Transform(tokens, []Range{Range{1, 1}})
 
-	origRunes := []rune("junegunn.choi")
+	origBytes := []byte("junegunn.choi")
 	for _, extended := range []bool{false, true} {
 		chunk := Chunk{
 			&Item{
-				text:        []rune("junegunn"),
-				origText:    &origRunes,
+				text:        util.RunesToChars([]rune("junegunn")),
+				origText:    &origBytes,
 				transformed: trans},
 		}
 		pattern.extended = extended
 		matches := pattern.matchChunk(&chunk)
-		if string(matches[0].text) != "junegunn" || string(*matches[0].origText) != "junegunn.choi" ||
+		if matches[0].text.ToString() != "junegunn" || string(*matches[0].origText) != "junegunn.choi" ||
 			matches[0].offsets[0][0] != 0 || matches[0].offsets[0][1] != 5 ||
 			!reflect.DeepEqual(matches[0].transformed, trans) {
 			t.Error("Invalid match result", matches)

src/terminal.go

@@ -564,7 +564,7 @@ func (t *Terminal) printHeader() {
 		trimmed, colors, newState := extractColor(lineStr, state, nil)
 		state = newState
 		item := &Item{
-			text:   []rune(trimmed),
+			text:   util.RunesToChars([]rune(trimmed)),
 			colors: colors,
 			rank:   buildEmptyRank(0)}
 
@@ -656,6 +656,17 @@ func trimLeft(runes []rune, width int) ([]rune, int32) {
 	return runes, trimmed
 }
 
+func overflow(runes []rune, max int) bool {
+	l := 0
+	for _, r := range runes {
+		l += runeWidth(r, l)
+		if l > max {
+			return true
+		}
+	}
+	return false
+}
+
 func (t *Terminal) printHighlighted(item *Item, bold bool, col1 int, col2 int, current bool) {
 	var maxe int
 	for _, offset := range item.offsets {
@@ -663,22 +674,20 @@ func (t *Terminal) printHighlighted(item *Item, bold bool, col1 int, col2 int, c
 	}
 
 	// Overflow
-	text := make([]rune, len(item.text))
-	copy(text, item.text)
+	text := make([]rune, item.text.Length())
+	copy(text, item.text.ToRunes())
 	offsets := item.colorOffsets(col2, bold, current)
 	maxWidth := t.window.Width - 3
 	maxe = util.Constrain(maxe+util.Min(maxWidth/2-2, t.hscrollOff), 0, len(text))
-	fullWidth := displayWidth(text)
-	if fullWidth > maxWidth {
+	if overflow(text, maxWidth) {
 		if t.hscroll {
 			// Stri..
-			matchEndWidth := displayWidth(text[:maxe])
-			if matchEndWidth <= maxWidth-2 {
+			if !overflow(text[:maxe], maxWidth-2) {
 				text, _ = trimRight(text, maxWidth-2)
 				text = append(text, []rune("..")...)
 			} else {
 				// Stri..
-				if matchEndWidth < fullWidth-2 {
+				if overflow(text[maxe:], 2) {
 					text = append(text[:maxe], []rune("..")...)
 				}
 				// ..ri..

src/tokenizer.go

@@ -18,7 +18,7 @@ type Range struct {
 
 // Token contains the tokenized part of the strings and its prefix length
 type Token struct {
-	text         []rune
+	text         util.Chars
 	prefixLength int
 	trimLength   int
 }
@@ -75,15 +75,15 @@ func ParseRange(str *string) (Range, bool) {
 	return newRange(n, n), true
 }
 
-func withPrefixLengths(tokens [][]rune, begin int) []Token {
+func withPrefixLengths(tokens []util.Chars, begin int) []Token {
 	ret := make([]Token, len(tokens))
 
 	prefixLength := begin
 	for idx, token := range tokens {
 		// Need to define a new local variable instead of the reused token to take
 		// the pointer to it
-		ret[idx] = Token{token, prefixLength, util.TrimLen(token)}
-		prefixLength += len(token)
+		ret[idx] = Token{token, prefixLength, token.TrimLength()}
+		prefixLength += token.Length()
 	}
 	return ret
 }
@@ -94,59 +94,60 @@ const (
 	awkWhite
 )
 
-func awkTokenizer(input []rune) ([][]rune, int) {
+func awkTokenizer(input util.Chars) ([]util.Chars, int) {
 	// 9, 32
-	ret := [][]rune{}
-	str := []rune{}
+	ret := []util.Chars{}
 	prefixLength := 0
 	state := awkNil
-	for _, r := range input {
+	numChars := input.Length()
+	begin := 0
+	end := 0
+	for idx := 0; idx < numChars; idx++ {
+		r := input.Get(idx)
 		white := r == 9 || r == 32
 		switch state {
 		case awkNil:
 			if white {
 				prefixLength++
 			} else {
-				state = awkBlack
-				str = append(str, r)
+				state, begin, end = awkBlack, idx, idx+1
 			}
 		case awkBlack:
-			str = append(str, r)
+			end = idx + 1
 			if white {
 				state = awkWhite
 			}
 		case awkWhite:
 			if white {
-				str = append(str, r)
+				end = idx + 1
 			} else {
-				ret = append(ret, str)
-				state = awkBlack
-				str = []rune{r}
+				ret = append(ret, input.Slice(begin, end))
+				state, begin, end = awkBlack, idx, idx+1
 			}
 		}
 	}
-	if len(str) > 0 {
-		ret = append(ret, str)
+	if begin < end {
+		ret = append(ret, input.Slice(begin, end))
 	}
 	return ret, prefixLength
 }
 
 // Tokenize tokenizes the given string with the delimiter
-func Tokenize(runes []rune, delimiter Delimiter) []Token {
+func Tokenize(text util.Chars, delimiter Delimiter) []Token {
 	if delimiter.str == nil && delimiter.regex == nil {
 		// AWK-style (\S+\s*)
-		tokens, prefixLength := awkTokenizer(runes)
+		tokens, prefixLength := awkTokenizer(text)
 		return withPrefixLengths(tokens, prefixLength)
 	}
 
-	var tokens []string
 	if delimiter.str != nil {
-		tokens = strings.Split(string(runes), *delimiter.str)
-		for i := 0; i < len(tokens)-1; i++ {
-			tokens[i] = tokens[i] + *delimiter.str
-		}
-	} else if delimiter.regex != nil {
-		str := string(runes)
+		return withPrefixLengths(text.Split(*delimiter.str), 0)
+	}
+
+	// FIXME performance
+	var tokens []string
+	if delimiter.regex != nil {
+		str := text.ToString()
 		for len(str) > 0 {
 			loc := delimiter.regex.FindStringIndex(str)
 			if loc == nil {
@@ -157,9 +158,9 @@ func Tokenize(runes []rune, delimiter Delimiter) []Token {
 			str = str[last:]
 		}
 	}
-	asRunes := make([][]rune, len(tokens))
+	asRunes := make([]util.Chars, len(tokens))
 	for i, token := range tokens {
-		asRunes[i] = []rune(token)
+		asRunes[i] = util.RunesToChars([]rune(token))
 	}
 	return withPrefixLengths(asRunes, 0)
 }
@@ -167,7 +168,7 @@ func Tokenize(runes []rune, delimiter Delimiter) []Token {
 func joinTokens(tokens []Token) []rune {
 	ret := []rune{}
 	for _, token := range tokens {
-		ret = append(ret, token.text...)
+		ret = append(ret, token.text.ToRunes()...)
 	}
 	return ret
 }
@@ -175,7 +176,7 @@ func joinTokens(tokens []Token) []rune {
 func joinTokensAsRunes(tokens []Token) []rune {
 	ret := []rune{}
 	for _, token := range tokens {
-		ret = append(ret, token.text...)
+		ret = append(ret, token.text.ToRunes()...)
 	}
 	return ret
 }
@@ -185,19 +186,19 @@ func Transform(tokens []Token, withNth []Range) []Token {
 	transTokens := make([]Token, len(withNth))
 	numTokens := len(tokens)
 	for idx, r := range withNth {
-		part := []rune{}
+		parts := []util.Chars{}
 		minIdx := 0
 		if r.begin == r.end {
 			idx := r.begin
 			if idx == rangeEllipsis {
-				part = append(part, joinTokensAsRunes(tokens)...)
+				parts = append(parts, util.RunesToChars(joinTokensAsRunes(tokens)))
 			} else {
 				if idx < 0 {
 					idx += numTokens + 1
 				}
 				if idx >= 1 && idx <= numTokens {
 					minIdx = idx - 1
-					part = append(part, tokens[idx-1].text...)
+					parts = append(parts, tokens[idx-1].text)
 				}
 			}
 		} else {
@@ -224,17 +225,32 @@ func Transform(tokens []Token, withNth []Range) []Token {
 			minIdx = util.Max(0, begin-1)
 			for idx := begin; idx <= end; idx++ {
 				if idx >= 1 && idx <= numTokens {
-					part = append(part, tokens[idx-1].text...)
+					parts = append(parts, tokens[idx-1].text)
 				}
 			}
 		}
+		// Merge multiple parts
+		var merged util.Chars
+		switch len(parts) {
+		case 0:
+			merged = util.RunesToChars([]rune{})
+		case 1:
+			merged = parts[0]
+		default:
+			runes := []rune{}
+			for _, part := range parts {
+				runes = append(runes, part.ToRunes()...)
+			}
+			merged = util.RunesToChars(runes)
+		}
+
 		var prefixLength int
 		if minIdx < numTokens {
 			prefixLength = tokens[minIdx].prefixLength
 		} else {
 			prefixLength = 0
 		}
-		transTokens[idx] = Token{part, prefixLength, util.TrimLen(part)}
+		transTokens[idx] = Token{merged, prefixLength, merged.TrimLength()}
 	}
 	return transTokens
 }

src/tokenizer_test.go

@@ -1,6 +1,10 @@
 package fzf
 
-import "testing"
+import (
+	"testing"
+
+	"github.com/junegunn/fzf/src/util"
+)
 
 func TestParseRange(t *testing.T) {
 	{
@@ -43,23 +47,23 @@ func TestParseRange(t *testing.T) {
 func TestTokenize(t *testing.T) {
 	// AWK-style
 	input := "  abc:  def:  ghi  "
-	tokens := Tokenize([]rune(input), Delimiter{})
-	if string(tokens[0].text) != "abc:  " || tokens[0].prefixLength != 2 || tokens[0].trimLength != 4 {
+	tokens := Tokenize(util.RunesToChars([]rune(input)), Delimiter{})
+	if tokens[0].text.ToString() != "abc:  " || tokens[0].prefixLength != 2 || tokens[0].trimLength != 4 {
 		t.Errorf("%s", tokens)
 	}
 
 	// With delimiter
-	tokens = Tokenize([]rune(input), delimiterRegexp(":"))
-	if string(tokens[0].text) != "  abc:" || tokens[0].prefixLength != 0 || tokens[0].trimLength != 4 {
+	tokens = Tokenize(util.RunesToChars([]rune(input)), delimiterRegexp(":"))
+	if tokens[0].text.ToString() != "  abc:" || tokens[0].prefixLength != 0 || tokens[0].trimLength != 4 {
 		t.Errorf("%s", tokens)
 	}
 
 	// With delimiter regex
-	tokens = Tokenize([]rune(input), delimiterRegexp("\\s+"))
-	if string(tokens[0].text) != "  " || tokens[0].prefixLength != 0 || tokens[0].trimLength != 0 ||
-		string(tokens[1].text) != "abc:  " || tokens[1].prefixLength != 2 || tokens[1].trimLength != 4 ||
-		string(tokens[2].text) != "def:  " || tokens[2].prefixLength != 8 || tokens[2].trimLength != 4 ||
-		string(tokens[3].text) != "ghi  " || tokens[3].prefixLength != 14 || tokens[3].trimLength != 3 {
+	tokens = Tokenize(util.RunesToChars([]rune(input)), delimiterRegexp("\\s+"))
+	if tokens[0].text.ToString() != "  " || tokens[0].prefixLength != 0 || tokens[0].trimLength != 0 ||
+		tokens[1].text.ToString() != "abc:  " || tokens[1].prefixLength != 2 || tokens[1].trimLength != 4 ||
+		tokens[2].text.ToString() != "def:  " || tokens[2].prefixLength != 8 || tokens[2].trimLength != 4 ||
+		tokens[3].text.ToString() != "ghi  " || tokens[3].prefixLength != 14 || tokens[3].trimLength != 3 {
 		t.Errorf("%s", tokens)
 	}
 }
@@ -67,7 +71,7 @@ func TestTokenize(t *testing.T) {
 func TestTransform(t *testing.T) {
 	input := "  abc:  def:  ghi:  jkl"
 	{
-		tokens := Tokenize([]rune(input), Delimiter{})
+		tokens := Tokenize(util.RunesToChars([]rune(input)), Delimiter{})
 		{
 			ranges := splitNth("1,2,3")
 			tx := Transform(tokens, ranges)
@@ -80,25 +84,25 @@ func TestTransform(t *testing.T) {
 			tx := Transform(tokens, ranges)
 			if string(joinTokens(tx)) != "abc:  def:  ghi:  def:  ghi:  jklabc:  " ||
 				len(tx) != 4 ||
-				string(tx[0].text) != "abc:  def:  " || tx[0].prefixLength != 2 ||
-				string(tx[1].text) != "ghi:  " || tx[1].prefixLength != 14 ||
-				string(tx[2].text) != "def:  ghi:  jkl" || tx[2].prefixLength != 8 ||
-				string(tx[3].text) != "abc:  " || tx[3].prefixLength != 2 {
+				tx[0].text.ToString() != "abc:  def:  " || tx[0].prefixLength != 2 ||
+				tx[1].text.ToString() != "ghi:  " || tx[1].prefixLength != 14 ||
+				tx[2].text.ToString() != "def:  ghi:  jkl" || tx[2].prefixLength != 8 ||
+				tx[3].text.ToString() != "abc:  " || tx[3].prefixLength != 2 {
 				t.Errorf("%s", tx)
 			}
 		}
 	}
 	{
-		tokens := Tokenize([]rune(input), delimiterRegexp(":"))
+		tokens := Tokenize(util.RunesToChars([]rune(input)), delimiterRegexp(":"))
 		{
 			ranges := splitNth("1..2,3,2..,1")
 			tx := Transform(tokens, ranges)
 			if string(joinTokens(tx)) != "  abc:  def:  ghi:  def:  ghi:  jkl  abc:" ||
 				len(tx) != 4 ||
-				string(tx[0].text) != "  abc:  def:" || tx[0].prefixLength != 0 ||
-				string(tx[1].text) != "  ghi:" || tx[1].prefixLength != 12 ||
-				string(tx[2].text) != "  def:  ghi:  jkl" || tx[2].prefixLength != 6 ||
-				string(tx[3].text) != "  abc:" || tx[3].prefixLength != 0 {
+				tx[0].text.ToString() != "  abc:  def:" || tx[0].prefixLength != 0 ||
+				tx[1].text.ToString() != "  ghi:" || tx[1].prefixLength != 12 ||
+				tx[2].text.ToString() != "  def:  ghi:  jkl" || tx[2].prefixLength != 6 ||
+				tx[3].text.ToString() != "  abc:" || tx[3].prefixLength != 0 {
 				t.Errorf("%s", tx)
 			}
 		}

src/util/chars.go

@@ -0,0 +1,156 @@
+package util
+
+import (
+	"unicode/utf8"
+)
+
+type Chars struct {
+	runes []rune
+	bytes []byte
+}
+
+// ToChars converts byte array into rune array
+func ToChars(bytea []byte) Chars {
+	var runes []rune
+	ascii := true
+	numBytes := len(bytea)
+	for i := 0; i < numBytes; {
+		if bytea[i] < utf8.RuneSelf {
+			if !ascii {
+				runes = append(runes, rune(bytea[i]))
+			}
+			i++
+		} else {
+			if ascii {
+				ascii = false
+				runes = make([]rune, i, numBytes)
+				for j := 0; j < i; j++ {
+					runes[j] = rune(bytea[j])
+				}
+			}
+			r, sz := utf8.DecodeRune(bytea[i:])
+			i += sz
+			runes = append(runes, r)
+		}
+	}
+	if ascii {
+		return Chars{bytes: bytea}
+	}
+	return Chars{runes: runes}
+}
+
+func RunesToChars(runes []rune) Chars {
+	return Chars{runes: runes}
+}
+
+func (chars *Chars) Get(i int) rune {
+	if chars.runes != nil {
+		return chars.runes[i]
+	}
+	return rune(chars.bytes[i])
+}
+
+func (chars *Chars) Length() int {
+	if chars.runes != nil {
+		return len(chars.runes)
+	}
+	return len(chars.bytes)
+}
+
+// TrimLength returns the length after trimming leading and trailing whitespaces
+func (chars *Chars) TrimLength() int {
+	var i int
+	len := chars.Length()
+	for i = len - 1; i >= 0; i-- {
+		char := chars.Get(i)
+		if char != ' ' && char != '\t' {
+			break
+		}
+	}
+	// Completely empty
+	if i < 0 {
+		return 0
+	}
+
+	var j int
+	for j = 0; j < len; j++ {
+		char := chars.Get(j)
+		if char != ' ' && char != '\t' {
+			break
+		}
+	}
+	return i - j + 1
+}
+
+func (chars *Chars) TrailingWhitespaces() int {
+	whitespaces := 0
+	for i := chars.Length() - 1; i >= 0; i-- {
+		char := chars.Get(i)
+		if char != ' ' && char != '\t' {
+			break
+		}
+		whitespaces++
+	}
+	return whitespaces
+}
+
+func (chars *Chars) ToString() string {
+	if chars.runes != nil {
+		return string(chars.runes)
+	}
+	return string(chars.bytes)
+}
+
+func (chars *Chars) ToRunes() []rune {
+	if chars.runes != nil {
+		return chars.runes
+	}
+	runes := make([]rune, len(chars.bytes))
+	for idx, b := range chars.bytes {
+		runes[idx] = rune(b)
+	}
+	return runes
+}
+
+func (chars *Chars) Slice(b int, e int) Chars {
+	if chars.runes != nil {
+		return Chars{runes: chars.runes[b:e]}
+	}
+	return Chars{bytes: chars.bytes[b:e]}
+}
+
+func (chars *Chars) Split(delimiter string) []Chars {
+	delim := []rune(delimiter)
+	numChars := chars.Length()
+	numDelim := len(delim)
+	begin := 0
+	ret := make([]Chars, 0, 1)
+
+	for index := 0; index < numChars; {
+		if index+numDelim <= numChars {
+			match := true
+			for off, d := range delim {
+				if chars.Get(index+off) != d {
+					match = false
+					break
+				}
+			}
+			// Found the delimiter
+			if match {
+				incr := Max(numDelim, 1)
+				ret = append(ret, chars.Slice(begin, index+incr))
+				index += incr
+				begin = index
+				continue
+			}
+		} else {
+			// Impossible to find the delimiter in the remaining substring
+			break
+		}
+		index++
+	}
+	if begin < numChars || len(ret) == 0 {
+		ret = append(ret, chars.Slice(begin, numChars))
+	}
+	return ret
+}

src/util/chars_test.go

@@ -0,0 +1,82 @@
+package util
+
+import "testing"
+
+func TestToCharsNil(t *testing.T) {
+	bs := Chars{bytes: []byte{}}
+	if bs.bytes == nil || bs.runes != nil {
+		t.Error()
+	}
+	rs := RunesToChars([]rune{})
+	if rs.bytes != nil || rs.runes == nil {
+		t.Error()
+	}
+}
+
+func TestToCharsAscii(t *testing.T) {
+	chars := ToChars([]byte("foobar"))
+	if chars.ToString() != "foobar" || chars.runes != nil {
+		t.Error()
+	}
+}
+
+func TestCharsLength(t *testing.T) {
+	chars := ToChars([]byte("\tabc한글  "))
+	if chars.Length() != 8 || chars.TrimLength() != 5 {
+		t.Error()
+	}
+}
+
+func TestCharsToString(t *testing.T) {
+	text := "\tabc한글  "
+	chars := ToChars([]byte(text))
+	if chars.ToString() != text {
+		t.Error()
+	}
+}
+
+func TestTrimLength(t *testing.T) {
+	check := func(str string, exp int) {
+		chars := ToChars([]byte(str))
+		trimmed := chars.TrimLength()
+		if trimmed != exp {
+			t.Errorf("Invalid TrimLength result for '%s': %d (expected %d)",
+				str, trimmed, exp)
+		}
+	}
+	check("hello", 5)
+	check("hello ", 5)
+	check("hello  ", 5)
+	check(" hello", 5)
+	check("  hello", 5)
+	check(" hello ", 5)
+	check("  hello  ", 5)
+	check("h   o", 5)
+	check("  h   o  ", 5)
+	check("         ", 0)
+}
+
+func TestSplit(t *testing.T) {
+	check := func(str string, delim string, tokens ...string) {
+		input := ToChars([]byte(str))
+		result := input.Split(delim)
+		if len(result) != len(tokens) {
+			t.Errorf("Invalid Split result for '%s': %d tokens found (expected %d): %s",
+				str, len(result), len(tokens), result)
+		}
+		for idx, token := range tokens {
+			if result[idx].ToString() != token {
+				t.Errorf("Invalid Split result for '%s': %s (expected %s)",
+					str, result[idx].ToString(), token)
+			}
+		}
+	}
+	check("abc:def::", ":", "abc:", "def:", ":")
+	check("abc:def::", "-", "abc:def::")
+	check("abc", "", "a", "b", "c")
+	check("abc", "a", "a", "bc")
+	check("abc", "ab", "ab", "c")
+	check("abc", "abc", "abc")
+	check("abc", "abcd", "abc")
+	check("", "abcd", "")
+}

src/util/util.go

@@ -7,18 +7,14 @@ import (
 	"os"
 	"os/exec"
 	"time"
-	"unicode/utf8"
 )
 
 // Max returns the largest integer
-func Max(first int, items ...int) int {
-	max := first
-	for _, item := range items {
-		if item > max {
-			max = item
-		}
+func Max(first int, second int) int {
+	if first >= second {
+		return first
 	}
-	return max
+	return second
 }
 
 // Min returns the smallest integer
@@ -84,58 +80,6 @@ func IsTty() bool {
 	return int(C.isatty(C.int(os.Stdin.Fd()))) != 0
 }
 
-// TrimRight returns rune array with trailing white spaces cut off
-func TrimRight(runes []rune) []rune {
-	var i int
-	for i = len(runes) - 1; i >= 0; i-- {
-		char := runes[i]
-		if char != ' ' && char != '\t' {
-			break
-		}
-	}
-	return runes[0 : i+1]
-}
-
-// BytesToRunes converts byte array into rune array
-func BytesToRunes(bytea []byte) []rune {
-	runes := make([]rune, 0, len(bytea))
-	for i := 0; i < len(bytea); {
-		if bytea[i] < utf8.RuneSelf {
-			runes = append(runes, rune(bytea[i]))
-			i++
-		} else {
-			r, sz := utf8.DecodeRune(bytea[i:])
-			i += sz
-			runes = append(runes, r)
-		}
-	}
-	return runes
-}
-
-// TrimLen returns the length of trimmed rune array
-func TrimLen(runes []rune) int {
-	var i int
-	for i = len(runes) - 1; i >= 0; i-- {
-		char := runes[i]
-		if char != ' ' && char != '\t' {
-			break
-		}
-	}
-	// Completely empty
-	if i < 0 {
-		return 0
-	}
-
-	var j int
-	for j = 0; j < len(runes); j++ {
-		char := runes[j]
-		if char != ' ' && char != '\t' {
-			break
-		}
-	}
-	return i - j + 1
-}
-
 // ExecCommand executes the given command with $SHELL
 func ExecCommand(command string) *exec.Cmd {
 	shell := os.Getenv("SHELL")

src/util/util_test.go

@@ -3,7 +3,7 @@ package util
 import "testing"
 
 func TestMax(t *testing.T) {
-	if Max(-2, 5, 1, 4, 3) != 5 {
+	if Max(-2, 5) != 5 {
 		t.Error("Invalid result")
 	}
 }
@@ -20,23 +20,3 @@ func TestContrain(t *testing.T) {
 		t.Error("Expected", 3)
 	}
 }
-
-func TestTrimLen(t *testing.T) {
-	check := func(str string, exp int) {
-		trimmed := TrimLen([]rune(str))
-		if trimmed != exp {
-			t.Errorf("Invalid TrimLen result for '%s': %d (expected %d)",
-				str, trimmed, exp)
-		}
-	}
-	check("hello", 5)
-	check("hello ", 5)
-	check("hello  ", 5)
-	check(" hello", 5)
-	check("  hello", 5)
-	check(" hello ", 5)
-	check("  hello  ", 5)
-	check("h   o", 5)
-	check("  h   o  ", 5)
-	check("         ", 0)
-}

test/fzf.vader

@@ -1,5 +1,6 @@
 Execute (Setup):
   let g:dir = fnamemodify(g:vader_file, ':p:h')
+  unlet! g:fzf_layout g:fzf_action g:fzf_history_dir
   Log 'Test directory: ' . g:dir
   Save &acd
 
@@ -69,6 +70,79 @@ Execute (fzf#run with dir option and autochdir when final cwd is same as dir):
   " Working directory changed due to &acd
   AssertEqual '/', getcwd()
 
+Execute (fzf#wrap):
+  AssertThrows fzf#wrap({'foo': 'bar'})
+
+  let opts = fzf#wrap('foobar')
+  Log opts
+  AssertEqual '~40%', opts.down
+  Assert opts.options =~ '--expect='
+  Assert !has_key(opts, 'sink')
+  Assert has_key(opts, 'sink*')
+
+  let opts = fzf#wrap('foobar', {}, 0)
+  Log opts
+  AssertEqual '~40%', opts.down
+
+  let opts = fzf#wrap('foobar', {}, 1)
+  Log opts
+  Assert !has_key(opts, 'down')
+
+  let opts = fzf#wrap('foobar', {'down': '50%'})
+  Log opts
+  AssertEqual '50%', opts.down
+
+  let opts = fzf#wrap('foobar', {'down': '50%'}, 1)
+  Log opts
+  Assert !has_key(opts, 'down')
+
+  let opts = fzf#wrap('foobar', {'sink': 'e'})
+  Log opts
+  AssertEqual 'e', opts.sink
+  Assert !has_key(opts, 'sink*')
+
+  let opts = fzf#wrap('foobar', {'options': '--reverse'})
+  Log opts
+  Assert opts.options =~ '--expect='
+  Assert opts.options =~ '--reverse'
+
+  let g:fzf_layout = {'window': 'enew'}
+  let opts = fzf#wrap('foobar')
+  Log opts
+  AssertEqual 'enew', opts.window
+
+  let opts = fzf#wrap('foobar', {}, 1)
+  Log opts
+  Assert !has_key(opts, 'window')
+
+  let opts = fzf#wrap('foobar', {'right': '50%'})
+  Log opts
+  Assert !has_key(opts, 'window')
+  AssertEqual '50%', opts.right
+
+  let opts = fzf#wrap('foobar', {'right': '50%'}, 1)
+  Log opts
+  Assert !has_key(opts, 'window')
+  Assert !has_key(opts, 'right')
+
+  let g:fzf_action = {'a': 'tabe'}
+  let opts = fzf#wrap('foobar')
+  Log opts
+  Assert opts.options =~ '--expect=a'
+  Assert !has_key(opts, 'sink')
+  Assert has_key(opts, 'sink*')
+
+  let opts = fzf#wrap('foobar', {'sink': 'e'})
+  Log opts
+  AssertEqual 'e', opts.sink
+  Assert !has_key(opts, 'sink*')
+
+  let g:fzf_history_dir = '/tmp'
+  let opts = fzf#wrap('foobar', {'options': '--color light'})
+  Log opts
+  Assert opts.options =~ '--history /tmp/foobar'
+  Assert opts.options =~ '--color light'
+
 Execute (Cleanup):
   unlet g:dir
   Restore

test/test_go.rb

@@ -36,6 +36,10 @@ end
 
 class Shell
   class << self
+    def unsets
+      'unset FZF_DEFAULT_COMMAND FZF_DEFAULT_OPTS FZF_CTRL_T_COMMAND FZF_CTRL_T_OPTS FZF_ALT_C_COMMAND FZF_ALT_C_OPTS FZF_CTRL_R_OPTS;'
+    end
+
     def bash
       'PS1= PROMPT_COMMAND= bash --rcfile ~/.fzf.bash'
     end
@@ -45,6 +49,10 @@ class Shell
       FileUtils.cp File.expand_path('~/.fzf.zsh'), '/tmp/fzf-zsh/.zshrc'
       'PS1= PROMPT_COMMAND= HISTSIZE=100 ZDOTDIR=/tmp/fzf-zsh zsh'
     end
+
+    def fish
+      'fish'
+    end
   end
 end
 
@@ -57,11 +65,11 @@ class Tmux
     @win =
       case shell
       when :bash
-        go("new-window -d -P -F '#I' '#{Shell.bash}'").first
+        go("new-window -d -P -F '#I' '#{Shell.unsets + Shell.bash}'").first
       when :zsh
-        go("new-window -d -P -F '#I' '#{Shell.zsh}'").first
+        go("new-window -d -P -F '#I' '#{Shell.unsets + Shell.zsh}'").first
       when :fish
-        go("new-window -d -P -F '#I' 'fish'").first
+        go("new-window -d -P -F '#I' '#{Shell.unsets + Shell.fish}'").first
       else
         raise "Unknown shell: #{shell}"
       end
@@ -153,12 +161,6 @@ class TestBase < Minitest::Test
      @temp_suffix].join '-'
   end
 
-  def setup
-    ENV.delete 'FZF_DEFAULT_OPTS'
-    ENV.delete 'FZF_CTRL_T_COMMAND'
-    ENV.delete 'FZF_DEFAULT_COMMAND'
-  end
-
   def readonce
     wait { File.exists?(tempname) }
     File.read(tempname)