Monaco-editor does not correctly evaluate negative-lookahead regex

Question

I used this ((?=(?!\bTODO\b)*?;).*)((?=.*?\bTODO\b).*)[^\n] regex to look for TODO inside commented text, its valid javascript regex, see this demo

But when I use

editor.getModel().findMatches("((?=(?!\\bTODO\\b)*?;).*)((?=.*?\\bTODO\\b).*)[^\\s]", true, true, true, null, true);

it returns empty FindMatch[]. Removing negative-lookahead ((?=.*?;).*)((?=.*?\bTODO\b).*)[^\n] it behave correctly, but it match invalid lines, obviously.

It is bug of monaco-editor, or just I do something wrong?

Answer 1

You can use

(;.*)(\bTODO\b.*)

See the regex demo.

Details

• (;.*) - Group 1: a ; and then any zero or more chars other than line break chars, as many as possible
• (\bTODO\b.*) - TODO as a whole word and then any zero or more chars other than line break chars, as many as possible.