Forward slashes are ignored when specifying string pattern

[svile]

🐛 Bug Report

It seems that in attempts to auto escape the regex for json compatibility the library strips out (or ignores) escaped /

To Reproduce

Steps to reproduce the behavior:

import S from 'fluent-json-schema';

const cronlike = S.string().pattern(
  /^((((\d+,)+\d+|(\d+(\/|-)\d+)|\d+|\*)\s?){5,6})$/,
);
console.log(cronlike.valueOf());

const cronlikeRegex = RegExp(
  /^((((\d+,)+\d+|(\d+(\/|-)\d+)|\d+|\*)\s?){5,6})$/,
);
console.log(cronlikeRegex);

Expected behavior

Forward slashes should also be escaped.

{
  '$schema': 'http://json-schema.org/draft-07/schema#',
  type: 'string',
  pattern: '^((((\\d+,)+\\d+|(\\d+(\\|-)\\d+)|\\d+|\\*)\\s?){5,6})$/'
}
/^((((\d+,)+\d+|(\d+(\/|-)\d+)|\d+|\*)\s?){5,6})$/

Your Environment

• node version: v14.16.1
• fluent-json-schema: 2.0.4
• os: Mac

[aboutlo]

Thank you @svile to report this.

Would you like to open a PR to fix it?
You can add the test case here: https://github.com/fastify/fluent-json-schema/blob/master/src/StringSchema.test.js#L97

[svile]

Actually, looks like I'll have some spare time today, so I'll take it.

[aboutlo]

resolved by #122