test: fix buggy getTTYfd() implementation

PR-URL: #17781
Ref: #17781 (comment)
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Timothy Gu <timothygu99@gmail.com>
Reviewed-By: Jon Moss <me@jonathanmoss.me>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

Author: Trott

test/sequential/test-async-wrap-getasyncid.js

@@ -249,28 +249,25 @@ if (common.hasCrypto) { // eslint-disable-line crypto-check
   // Do our best to grab a tty fd.
   function getTTYfd() {
     const tty = require('tty');
-    let tty_fd = 0;
-    if (!tty.isatty(tty_fd)) tty_fd++;
-    else if (!tty.isatty(tty_fd)) tty_fd++;
-    else if (!tty.isatty(tty_fd)) tty_fd++;
-    else {
+    let ttyFd = [0, 1, 2].find(tty.isatty);
+    if (ttyFd === undefined) {
       try {
-        tty_fd = fs.openSync('/dev/tty');
+        ttyFd = fs.openSync('/dev/tty');
       } catch (e) {
         // There aren't any tty fd's available to use.
         return -1;
       }
     }
-    return tty_fd;
+    return ttyFd;
   }
 
-  const tty_fd = getTTYfd();
-  if (tty_fd >= 0) {
+  const ttyFd = getTTYfd();
+  if (ttyFd >= 0) {
     const tty_wrap = process.binding('tty_wrap');
     // fd may still be invalid, so guard against it.
     const handle = (() => {
       try {
-        return new tty_wrap.TTY(tty_fd, false);
+        return new tty_wrap.TTY(ttyFd, false);
       } catch (e) {
         return null;
       }