How do I use regex to convert Slack URLs to BB Code?

Question

I'm trying to use regex to convert Slack's version of markdown formatting to BB Code. I'm stuck on links at the moment. Slack formats like this:

<www.url.com|This is the actual text>
<www.url.com>

BB Code formats like this:

[url=www.url.com]This is the actual text[/url]
[url]www.url.com[/url]

I'm dealing with the first type using this (in javascript)

string.replace(/\<([\s\S]+)(?=\|)\|([\s\S]*?)\>/gm, "[url=$1]$2[/url]"

I'm struggling to make a second rule that will only match text between <...> if there isn't a | in the string. Can anyone help me out?

Also if there's a neat way of dealing with both options in one go then let me know!

Answer 1

You can use

const text = `<www.url.com|This is the actual text>
<www.url.com>`;
console.log( text.replace(/<([^<>|]*)(?:\|([^<>]*))?>/g, (x, url, text) => text !== undefined ?
 `[url=${url}]${text}[/url]` : `[url]${url}[/url]`) )

See the regex demo. Details:

• < - a < char (please NEVER escape this char in any regex flavor if you plan to match a < char)
• ([^<>|]*) - Group 1: any zero or more chars other than <, > and |
• (?:\|([^<>]*))? - an optional non-capturing group matching one or zero occurrences of a | and then any zero or more chars other than < and > captured into Group 2
• > - a > char (again, please never escape the > literal char in any regex flavor).