readline: processing \u2028 and \u2029

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.

首先运行提供的 fs/readline.createInterface 复现代码，并将其对 \u2028 和 \u2029 的处理与 JavaScript RegExp 的换行符进行比较。查看 readline 的行为和相关讨论，以决定这是 bug、文档问题还是有意设计的行为；完成的标准是记录该决定，并通过回归测试覆盖任何已达成一致的行为。