Hi @kazurayam and all,
The do {} while … loop was added at the version 3.0 of Groovy language
https://docs.groovy-lang.org/docs/groovy-3.0.0/html/documentation/#_do_while_loop
However, as far as I am aware, Katalon team has no intention to move to Groovy v3.0 in Katalon Studio.
Thanks for mentioning this again.
Katalon Studio team are working on a major change that includes Eclipse framework (4.16 to latest), Groovy (2.0.20 to 3.0.x) and Java upgrade (Java 8 to Java 17).
We hope this change will improve Katalon Studio performance especially with Groovy editor and allow user to script with latest Java and Groovy technologies.
We cannot confirm the ETA for now but we hope we can publish a pre-release version in next couple of months.