Katalon Studio v8.1.0 bundles Groovy v2.4.x, which is old one. In the current Katalon Studio you can use groovy.util.slurpersupport.GPathResult
.
However, the latest version of Groovy v3.x.x has deprecated this class.
The package is renamed:
In case Katalon Studio change the Groovy version from v2.4.x to v3.x.x in future, your custom keyword will not work. You have to rewrite the import statement. Please note this.
Is it likely to happen? — I don’t know. Ask Katalon Team.