Use winpty to launch fzf in Git bash (mintty)

Close #3806

Known limitation:
* --height cannot be used

src/tmux.go

@@ -1,81 +1,24 @@
 package fzf
 
 import (
-	"bufio"
-	"errors"
-	"fmt"
-	"io"
 	"os"
 	"os/exec"
-	"path/filepath"
-	"strings"
-	"time"
 
 	"github.com/junegunn/fzf/src/tui"
-	"github.com/junegunn/fzf/src/util"
 )
 
-func escapeSingleQuote(str string) string {
-	return "'" + strings.ReplaceAll(str, "'", "'\\''") + "'"
-}
-
 func runTmux(args []string, opts *Options) (int, error) {
-	ns := time.Now().UnixNano()
-
-	output := filepath.Join(os.TempDir(), fmt.Sprintf("fzf-tmux-output-%d", ns))
-	if err := mkfifo(output, 0666); err != nil {
-		return ExitError, err
-	}
-	defer os.Remove(output)
-
-	// Find fzf executable
-	fzf := "fzf"
-	if found, err := os.Executable(); err == nil {
-		fzf = found
-	}
-
 	// Prepare arguments
-	args = append([]string{"--bind=ctrl-z:ignore"}, args...)
+	fzf := args[0]
+	args = append([]string{"--bind=ctrl-z:ignore"}, args[1:]...)
 	if opts.BorderShape == tui.BorderUndefined {
 		args = append(args, "--border")
 	}
-	args = append(args, "--no-height")
-	args = append(args, "--no-tmux")
-	argStr := ""
+	argStr := escapeSingleQuote(fzf)
 	for _, arg := range args {
-		// %q formatting escapes $'foo\nbar' to "foo\nbar"
 		argStr += " " + escapeSingleQuote(arg)
 	}
-	argStr += ` --tmux-script "$0"`
-
-	// Build command
-	var command string
-	if opts.Input == nil && util.IsTty() {
-		command = fmt.Sprintf(`%q%s > %q`, fzf, argStr, output)
-	} else {
-		input := filepath.Join(os.TempDir(), fmt.Sprintf("fzf-tmux-input-%d", ns))
-		if err := mkfifo(input, 0644); err != nil {
-			return ExitError, err
-		}
-		defer os.Remove(input)
-
-		go func() {
-			inputFile, err := os.OpenFile(input, os.O_WRONLY, 0)
-			if err != nil {
-				return
-			}
-			if opts.Input == nil {
-				io.Copy(inputFile, os.Stdin)
-			} else {
-				for item := range opts.Input {
-					fmt.Fprint(inputFile, item+opts.PrintSep)
-				}
-			}
-			inputFile.Close()
-		}()
-
-		command = fmt.Sprintf(`%q%s < %q > %q`, fzf, argStr, input, output)
-	}
+	argStr += ` --no-tmux --no-height`
 
 	// Get current directory
 	dir, err := os.Getwd()
@@ -106,65 +49,9 @@ func runTmux(args []string, opts *Options) (int, error) {
 	tmuxArgs = append(tmuxArgs, "-w"+opts.Tmux.width.String())
 	tmuxArgs = append(tmuxArgs, "-h"+opts.Tmux.height.String())
 
-	// To ensure that the options are processed by a POSIX-compliant shell,
-	// we need to write the command to a temporary file and execute it with sh.
-	exports := os.Environ()
-	for idx, pairStr := range exports {
-		pair := strings.SplitN(pairStr, "=", 2)
-		exports[idx] = fmt.Sprintf("export %s=%s", pair[0], escapeSingleQuote(pair[1]))
-	}
-	temp := writeTemporaryFile(append(exports, command), "\n")
-	defer os.Remove(temp)
-	tmuxArgs = append(tmuxArgs, "sh", temp)
-
-	// Take the output
-	go func() {
-		outputFile, err := os.OpenFile(output, os.O_RDONLY, 0)
-		if err != nil {
-			return
-		}
-		if opts.Output == nil {
-			io.Copy(os.Stdout, outputFile)
-		} else {
-			reader := bufio.NewReader(outputFile)
-			sep := opts.PrintSep[0]
-			for {
-				item, err := reader.ReadString(sep)
-				if err != nil {
-					break
-				}
-				opts.Output <- item
-			}
-		}
-
-		outputFile.Close()
-	}()
-
-	cmd := exec.Command("tmux", tmuxArgs...)
-	if err := cmd.Run(); err != nil {
-		if exitError, ok := err.(*exec.ExitError); ok {
-			code := exitError.ExitCode()
-			if code == ExitBecome {
-				data, err := os.ReadFile(temp)
-				if err != nil {
-					return ExitError, err
-				}
-				elems := strings.Split(string(data), "\x00")
-				if len(elems) < 1 {
-					return ExitError, errors.New("invalid become command")
-				}
-				command := elems[0]
-				env := []string{}
-				if len(elems) > 1 {
-					env = elems[1:]
-				}
-				os.Remove(temp)
-				executor := util.NewExecutor(opts.WithShell)
-				executor.Become(tui.TtyIn(), env, command)
-			}
-			return code, err
-		}
-	}
-
-	return ExitOk, nil
+	return runProxy(argStr, func(temp string) *exec.Cmd {
+		sh, _ := sh()
+		tmuxArgs = append(tmuxArgs, sh, temp)
+		return exec.Command("tmux", tmuxArgs...)
+	}, opts, true)
 }