Automatically append some generated comment on a transition.

In this case we add a comment if a user resolved an issue which had unresolved subtasks:

import com.atlassian.jira.component.ComponentAccessor

def commentManager = ComponentAccessor.getCommentManager()
def user = ComponentAccessor.getJiraAuthenticationContext().getLoggedInUser()

if (issue.subTaskObjects.any { !it.resolution }) {
    commentManager.create(
        issue,
        user,
        "I resolved this issue even though there were unresolved sub-tasks... slapped wrists",
        false) // <1>
}

Line 11: Change false to true in order to raise an IssueCommented event for notifications.