Error reading stdin with gren run

[blaix]

This program:

module Main exposing (main)

import Node
import Stream
import Stream.Log
import Task

main =
    Node.defineSimpleProgram <| \env ->
        Stream.readBytesAsString env.stdin
            |> Task.mapError (Debug.log "Read stream error")
            |> Task.onError (\_ -> Task.succeed "")
            |> Task.andThen (Stream.Log.line env.stdout)
            |> Node.endSimpleProgram

Executes correctly when compiled and run:

❯ gren make Main
Success! Compiled 1 module.

    Main ───> app

❯ node app
test
test

But errors when run with gren run:

❯ gren run Main
test
Something went wrong when communicating with compiler backend: Cancelled:

[blaix]

I have the debug and print to make sure it's actually working correctly when compiled (it does) and to see if there's an error value (there's not), but I get the same error when I remove them so it's definitely the read causing the crash.

[robinheghan]

You need to use RedirectTerminalIO (look at the CompilerInitialized message).

Alternatively you could spawn the child process with an Integrated connection, but I’m not sure if the exit code is set correctly in that case.

[blaix]

Attempt at using RedirectTerminalIO here: 4e1934f

But it's failing with a stream locked error on the stdin redirect...