'become' to use --with-shell / Allow 'become' on Windows

man/man1/fzf.1

@@ -1451,8 +1451,6 @@ call.
 
     \fBfzf --bind "enter:become(vim {})"\fR
 
-\fBbecome(...)\fR is not supported on Windows.
-
 .SS RELOAD INPUT
 
 \fBreload(...)\fR action is used to dynamically update the input list

src/options.go

@@ -1329,10 +1329,6 @@ func parseActionList(masked string, original string, prevActions []*action, putA
 					actions = append(actions, &action{t: t, a: actionArg})
 				}
 				switch t {
-				case actBecome:
-					if util.IsWindows() {
-						exit("become action is not supported on Windows")
-					}
 				case actUnbind, actRebind:
 					parseKeyChordsImpl(actionArg, spec[0:offset]+" target required", exit)
 				case actChangePreviewWindow:

src/terminal.go

@@ -7,7 +7,6 @@ import (
 	"io"
 	"math"
 	"os"
-	"os/exec"
 	"os/signal"
 	"regexp"
 	"sort"
@@ -3376,27 +3375,21 @@ func (t *Terminal) Loop() {
 				valid, list := t.buildPlusList(a.a, false)
 				if valid {
 					command := t.replacePlaceholder(a.a, false, string(t.input), list)
-					shell := os.Getenv("SHELL")
-					if len(shell) == 0 {
-						shell = "sh"
-					}
-					shellPath, err := exec.LookPath(shell)
-					if err == nil {
-						t.tui.Close()
-						if t.history != nil {
-							t.history.append(string(t.input))
-						}
-						/*
-							FIXME: It is not at all clear why this is required.
-							The following command will report 'not a tty', unless we open
-							/dev/tty *twice* after closing the standard input for 'reload'
-							in Reader.terminate().
-								: | fzf --bind 'start:reload:ls' --bind 'enter:become:tty'
-						*/
-						tui.TtyIn()
-						util.SetStdin(tui.TtyIn())
-						syscall.Exec(shellPath, []string{shell, "-c", command}, os.Environ())
+					t.tui.Close()
+					if t.history != nil {
+						t.history.append(string(t.input))
 					}
+
+					/*
+					 FIXME: It is not at all clear why this is required.
+					 The following command will report 'not a tty', unless we open
+					 /dev/tty *twice* after closing the standard input for 'reload'
+					 in Reader.terminate().
+
+					   while : | fzf --bind 'start:reload:ls' --bind 'load:become:tty'; do echo; done
+					*/
+					tui.TtyIn()
+					t.executor.Become(tui.TtyIn(), t.environ(), command)
 				}
 			case actExecute, actExecuteSilent:
 				t.executeCommand(a.a, false, a.t == actExecuteSilent, false, false)

src/util/util_unix.go

@@ -56,6 +56,16 @@ func (x *Executor) QuoteEntry(entry string) string {
 	return "'" + x.escaper.Replace(entry) + "'"
 }
 
+func (x *Executor) Become(stdin *os.File, environ []string, command string) {
+	SetStdin(stdin)
+	shellPath, err := exec.LookPath(x.shell)
+	if err == nil {
+		shellPath = x.shell
+	}
+	args := append([]string{shellPath}, append(x.args, command)...)
+	syscall.Exec(shellPath, args, environ)
+}
+
 // KillCommand kills the process for the given command
 func KillCommand(cmd *exec.Cmd) error {
 	return syscall.Kill(-cmd.Process.Pid, syscall.SIGKILL)

src/util/util_windows.go

@@ -64,6 +64,21 @@ func (x *Executor) ExecCommand(command string, setpgid bool) *exec.Cmd {
 	return cmd
 }
 
+func (x *Executor) Become(stdin *os.File, environ []string, command string) {
+	cmd := x.ExecCommand(command, false)
+	cmd.Stdin = stdin
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	cmd.Env = environ
+	err := cmd.Run()
+	if err != nil {
+		if exitError, ok := err.(*exec.ExitError); ok {
+			Exit(exitError.ExitCode())
+		}
+	}
+	Exit(0)
+}
+
 func (x *Executor) QuoteEntry(entry string) string {
 	if strings.Contains(x.shell, "cmd") {
 		// backslash escaping is done here for applications