Debugger throwing error

[shaycraft]

Sort of similar to issue #25. Whenever I run something with readline-sync with the --debug flag, a script that runs fine without it gives this error:
src\debug-agent.cc:149: Assertion(err) == (0)' failed.`

This is under node 6.10.1, npm 3.10.10. It does this on my home computer (Windows 10) and work as well (Windows 7): Simplest steps to reproduce:

create a file main.js containing this line:
var rl = require('readline-sync');

run with node main.js should be no errors.
run with node --debug main.js and results in the above mentioned error.

UPDATE: Verified too that this happens in Linux as well under node 7.7, same error.

[anseki]

Hi @shaycraft, thank you for the comment.

So, is that message an error that means that your script was aborted?
I tried a script with --debug, and it worked fine with that message.
(The layout is broken in your debug agent because readlineSync uses TTY.)

[shaycraft]

The script does not abort and does run correctly with the --debug option, but I cannot debug which is the issue. I suppose what you are saying about TTY makes sense, wonder if there is a way around this.

[anseki]

Do you mean that your debugger such as node inspector doesn't work?

[shaycraft]

Right, in this case I'm using VS Code. It times out and says it's unresponsive, which I assume is because of the tty.

[anseki]

I see.
Since readlineSync is a module to read/write TTY, of course it doesn't work in environment that has no TTY.
I.e. that is a correct behavior.

You have to emulate input via TTY if you want to run it for debugging without TTY. For example, you can use stubs and mocks via library such as Sinon.JS for unit testing.

[shaycraft]

Cool I'll look into it. I'll close this issue then.

[anseki]

😄