Add --with-shell for shelling out with different command and flags (#3746)

Close #3732

src/terminal.go

@@ -7,7 +7,6 @@ import (
 	"io"
 	"math"
 	"os"
-	"os/exec"
 	"os/signal"
 	"regexp"
 	"sort"
@@ -245,6 +244,7 @@ type Terminal struct {
 	listenUnsafe       bool
 	borderShape        tui.BorderShape
 	cleanExit          bool
+	executor           *util.Executor
 	paused             bool
 	border             tui.Window
 	window             tui.Window
@@ -640,7 +640,7 @@ func evaluateHeight(opts *Options, termHeight int) int {
 }
 
 // NewTerminal returns new Terminal object
-func NewTerminal(opts *Options, eventBox *util.EventBox) *Terminal {
+func NewTerminal(opts *Options, eventBox *util.EventBox, executor *util.Executor) *Terminal {
 	input := trimQuery(opts.Query)
 	var delay time.Duration
 	if opts.Tac {
@@ -736,6 +736,7 @@ func NewTerminal(opts *Options, eventBox *util.EventBox) *Terminal {
 		previewLabel:       nil,
 		previewLabelOpts:   opts.PreviewLabel,
 		cleanExit:          opts.ClearOnExit,
+		executor:           executor,
 		paused:             opts.Phony,
 		cycle:              opts.Cycle,
 		headerVisible:      true,
@@ -2522,6 +2523,7 @@ type replacePlaceholderParams struct {
 	allItems   []*Item
 	lastAction actionType
 	prompt     string
+	executor   *util.Executor
 }
 
 func (t *Terminal) replacePlaceholder(template string, forcePlus bool, input string, list []*Item) string {
@@ -2535,6 +2537,7 @@ func (t *Terminal) replacePlaceholder(template string, forcePlus bool, input str
 		allItems:   list,
 		lastAction: t.lastAction,
 		prompt:     t.promptString,
+		executor:   t.executor,
 	})
 }
 
@@ -2595,7 +2598,7 @@ func replacePlaceholder(params replacePlaceholderParams) string {
 		case escaped:
 			return match
 		case match == "{q}" || match == "{fzf:query}":
-			return quoteEntry(params.query)
+			return params.executor.QuoteEntry(params.query)
 		case match == "{}":
 			replace = func(item *Item) string {
 				switch {
@@ -2608,13 +2611,13 @@ func replacePlaceholder(params replacePlaceholderParams) string {
 				case flags.file:
 					return item.AsString(params.stripAnsi)
 				default:
-					return quoteEntry(item.AsString(params.stripAnsi))
+					return params.executor.QuoteEntry(item.AsString(params.stripAnsi))
 				}
 			}
 		case match == "{fzf:action}":
 			return params.lastAction.Name()
 		case match == "{fzf:prompt}":
-			return quoteEntry(params.prompt)
+			return params.executor.QuoteEntry(params.prompt)
 		default:
 			// token type and also failover (below)
 			rangeExpressions := strings.Split(match[1:len(match)-1], ",")
@@ -2648,7 +2651,7 @@ func replacePlaceholder(params replacePlaceholderParams) string {
 					str = strings.TrimSpace(str)
 				}
 				if !flags.file {
-					str = quoteEntry(str)
+					str = params.executor.QuoteEntry(str)
 				}
 				return str
 			}
@@ -2688,7 +2691,7 @@ func (t *Terminal) executeCommand(template string, forcePlus bool, background bo
 		return line
 	}
 	command := t.replacePlaceholder(template, forcePlus, string(t.input), list)
-	cmd := util.ExecCommand(command, false)
+	cmd := t.executor.ExecCommand(command, false)
 	cmd.Env = t.environ()
 	t.executing.Set(true)
 	if !background {
@@ -2965,7 +2968,7 @@ func (t *Terminal) Loop() {
 				if items[0] != nil {
 					_, query := t.Input()
 					command := t.replacePlaceholder(commandTemplate, false, string(query), items)
-					cmd := util.ExecCommand(command, true)
+					cmd := t.executor.ExecCommand(command, true)
 					env := t.environ()
 					if pwindowSize.Lines > 0 {
 						lines := fmt.Sprintf("LINES=%d", pwindowSize.Lines)
@@ -3372,27 +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)