when i accidentally hit enter before propts appeared, propts will receive this enter

[kongku]

when i accidentally hit enter before propts appeared, propts will receive this enter，How to fix this situation？

import { select } from '@inquirer/prompts'

console.log('wait.....')

setTimeout(() => {
  select({
    message: 'select',
    choices: [
      { name: 'a', value: 'a' },
      { name: 'b', value: 'b' },
      { name: 'c', value: 'c' },
    ],
  })
}, 2000)

[SBoudrias]

Thanks for the bug report and the code example. I can reproduce it with your snippet easily.

This is a weird behaviour because at the time we press "enter", the readline isn't set, and there's no keypress listener. So it's like there's some kind of replay of the events.

[PoHengLinTW]

Using a debugger helps me find out what might be the cause of the problem.

In create-prompt.mts

  const prompt: Prompt<Value, Config> = (config, context) => {
    // Default `input` to stdin
    const input = context?.input ?? process.stdin;

    // Add mute capabilities to the output
    const output = new MuteStream();
    output.pipe(context?.output ?? process.stdout);

    const rl = readline.createInterface({
      terminal: true,
      input,
      output,
    }) as InquirerReadline;
    const screen = new ScreenManager(rl);

Even though rl is set here, the ReadableStream (process.stdin) already has data from user in the stream when an enter key is pressed.

After the 2 seconds wait, the readline would register keypress event automatically for the input ("This is automatically called by any readline instance on its input if the input is a terminal." from Node's doc) and the data hasn't been read in input would emit the keypress events.

Haven't thought of a good solution to the problem for now, but I would like to share what I found.

[SBoudrias]

Yeah that's the problem. I tried a few approach, but can't get to flush the stdin before the prompt shows...