nodemon crashes when --help is redirected to a file

[khardix]

• nodemon -v: master: 3d2320f
• node -v: v14.14.0
• Operating system/terminal environment: Fedora 33 (Linux), ZSH
• Command you ran: node bin/nodemon.js --help >help.log

Expected behaviour

No output; help.log contains the help message.

Actual behaviour

$ node bin/nodemon.js --help >help.log

/home/.../nodemon/lib/nodemon.js:42
    process.stdout._handle.setBlocking(true); // nodejs/node#6456
                           ^

TypeError: Cannot read property 'setBlocking' of undefined
    at nodemon (/home/.../nodemon/lib/nodemon.js:42:28)
    at Object.<anonymous> (/home/.../nodemon/bin/nodemon.js:7:1)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
    at Module.load (internal/modules/cjs/loader.js:928:32)
    at Function.Module._load (internal/modules/cjs/loader.js:769:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:72:12)
    at internal/main/run_main_module.js:17:47

Steps to reproduce

Run the command with the redirect.

Note

The following patch seems to fix the issue; however, since I did not yet dedicated enough time to understand the test suite (I'm not a JavaScript developer), I was unable to add appropriate tests for it. That is also the reason I'm submitting this as a bug report rather than a pull request.

diff --git a/lib/nodemon.js b/lib/nodemon.js
index b3badea..ce649cb 100644
--- a/lib/nodemon.js
+++ b/lib/nodemon.js
@@ -39,7 +39,9 @@ function nodemon(settings) {
   }
 
   if (settings.help) {
-    process.stdout._handle.setBlocking(true); // nodejs/node#6456
+    if (process.stdout.isTTY) {
+      process.stdout._handle.setBlocking(true); // nodejs/node#6456
+    }
     console.log(help(settings.help));
     if (!config.required) {
       process.exit(0);

[stale]

This issue has been automatically marked as idle and stale because it hasn't had any recent activity. It will be automtically closed if no further activity occurs. If you think this is wrong, or the problem still persists, just pop a reply in the comments and @remy will (try!) to follow up.
Thank you for contributing <3

[remy]

@khardix that fix was on point - and doesn't really need a test to go along side as it doesn't affect core running. I've got a PR (bit late) but it'll go live today.