readline: processing \u2028 and \u2029

[vsemozhetbyt]

Not sure if we should fix, document, or ignore this and if it has been discussed, so to be on the safe side.

Currently, \u2028 and \u2029 are considered as line breaks by JavaScript RegExps, while they are ignored by the readline:

'use strict';

const fs = require('fs');
const readline = require('readline');

const str = '123\n456\r123\u{2028}456\u{2029}789';

console.log(str.split(/^/mu));

fs.writeFileSync('readline-test.txt', str, 'utf8');

const rl = readline.createInterface({
  input: fs.createReadStream('readline-test.txt', 'utf8'),
  crlfDelay: Infinity,
});

rl.on('line', console.log);

Feel free to close if this is a wontfix.

[addaleax]

I think consistency with JS RegExps is a good argument to do this.

[apapirovski]

I agree with changing this for consistency.

[BridgeAR]

If we want to support this, should it also be an opt-in as is for regular expressions?

[dario-piotrowicz]

If we want to support this, should it also be an opt-in as is for regular expressions?

Are they actually opt-in in regular expressions though?

To me it looks like they always get interpreted as newlines (with or without the u flag):