/*
* This example script field script should configured as a 'Custom Script Field' and shows how to get the start date from the active sprint and to display this inside a script field. 
* This example uses the HAPI API for Jira Data Center
* "All right, title and interest in this code snippet shall remain the exclusive intellectual property of Adaptavist Group Ltd and its affiliates. Customers with a valid ScriptRunner
* license shall be granted a  non-exclusive, non-transferable, freely revocable right to use this code snippet only within their own instance of Atlassian products. This licensing notice cannot be removed or
* amended and must be included in any circumstances where the code snippet is shared by You or a third party." 
*/

def activeSprints = issue.getSprints().findAll { item ->
    item.toString().contains("state=ACTIVE")
} 

def startDate = activeSprints.collect { item ->
  item.startDate
}

return startDate.toString()