Christoph Thiede uploaded a new version of Regex-Tests-Core to project The Trunk:
http://source.squeak.org/trunk/Regex-Tests-Core-ct.18.mcz

==================== Summary ====================

Name: Regex-Tests-Core-ct.18
Author: ct
Time: 23 August 2021, 6:28:04.668768 pm
UUID: c1fff7b6-7b19-9a4f-b8cc-6011556e3e96
Ancestors: Regex-Tests-Core-mt.16

Adds regression test for a bug while parsing lookaround-like regexes.

=============== Diff against Regex-Tests-Core-mt.16 ===============

Item was removed:
- ----- Method: RxParserTest>>testLookaroundNullable (in category 'tests') -----
- testLookaroundNullable
- 
- 	self should: ['(?<=a)?b' asRegex] raise: RegexSyntaxError.!

Item was added:
+ ----- Method: RxParserTest>>testLookaroundParser (in category 'tests') -----
+ testLookaroundParser
+ 
+ 	self should: ['(?<=a)?b' asRegex] raise: RegexSyntaxError.
+ 	self should: ['(?<a)b' asRegex] raise: RegexSyntaxError.!