JavaScript无法正确拆分字符串

根据 ECMA-262 §21.1.3.19 String.prototype.split ,

String.prototype.split ( separator, limit )

这些事件不是返回数组中任何子字符串的一部分,而是用来分割字符串值 .

let s = new String("All the world's a stage, And all the men and women merely players;");
console.log(s.split(/( |o)men /));

预期产量:

[
  "All the world's a stage, And all the",
  'and w',
  'merely players;'
]

[
  "All the world's a stage, And all the",
  ' ',
  'and w',
  'o',
  'merely players;'
]

这里发生了什么事?我该怎么写才能和“男人”或“预兆”匹配呢?

环境:

~ $ node --version
v13.8.0

为了我的笔记:

import re
s = "All the world's a stage, And all the men and women merely players;"
print(re.compile("( |o)men ").split(s))
  #=> ["All the world's a stage, And all the", ' ', 'and w', 'o', 'merely players;']
print(re.compile("(?: |o)men ").split(s))
  #=> ["All the world's a stage, And all the", 'and w', 'merely players;']

也许有合理的理由或者实际的用例来解释这种奇怪的(至少对我来说)行为。。。