Jenkins Groovy how to call methods from @NonCPS method without ending pipeline
I've resolved this issue essentially by doing the following:
import groovy.json.JsonSlurperdef myMethod(String json) { def jsonSlurper = new JsonSlurper() def jsonObject = jsonSlurper(json) jsonSlurper = null for(int i = 0; i < jsonObject.size(); i++) { switch(jsonObject[i].name) { case "foo": doAThing(jsonObject[i]) break case "bar": doAnotherThing(jsonObject[i]) break } }}Immediately destroy the JsonSlurper instance after it's used, remove @NonCPS annotation, switch to a c-style for loop instead of each.
Just to clarify, this is documented as an unsupported feature - https://github.com/jenkinsci/workflow-cps-plugin/#technical-design
You may not call regular (CPS-transformed) methods, or Pipeline steps, from a @NonCPS method, so they are best used for performing some calculations before passing a summary back to the main script.