Use $SHELL to start $FZF_DEFAULT_COMMAND (#481)

src/reader.go

@@ -4,7 +4,6 @@ import (
 	"bufio"
 	"io"
 	"os"
-	"os/exec"
 
 	"github.com/junegunn/fzf/src/util"
 )
@@ -59,7 +58,7 @@ func (r *Reader) readFromStdin() {
 }
 
 func (r *Reader) readFromCommand(cmd string) {
-	listCommand := exec.Command("sh", "-c", cmd)
+	listCommand := util.ExecCommand(cmd)
 	out, err := listCommand.StdoutPipe()
 	if err != nil {
 		return

src/terminal.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"fmt"
 	"os"
-	"os/exec"
 	"os/signal"
 	"regexp"
 	"sort"
@@ -720,11 +719,7 @@ func quoteEntry(entry string) string {
 
 func executeCommand(template string, replacement string) {
 	command := strings.Replace(template, "{}", replacement, -1)
-	shell := os.Getenv("SHELL")
-	if len(shell) == 0 {
-		shell = "sh"
-	}
-	cmd := exec.Command(shell, "-c", command)
+	cmd := util.ExecCommand(command)
 	cmd.Stdin = os.Stdin
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr

src/util/util.go

@@ -5,6 +5,7 @@ import "C"
 
 import (
 	"os"
+	"os/exec"
 	"time"
 	"unicode/utf8"
 )
@@ -126,3 +127,12 @@ func TrimLen(runes []rune) int {
 	}
 	return i - j + 1
 }
+
+// ExecCommand executes the given command with $SHELL
+func ExecCommand(command string) *exec.Cmd {
+	shell := os.Getenv("SHELL")
+	if len(shell) == 0 {
+		shell = "sh"
+	}
+	return exec.Command(shell, "-c", command)
+}