How can I Restrict Custom Date field value on subtask based on Parent issue?

[Inayat Nahvi]

Hi,

I have a custom date field called "Completion Date" on both standard issues and subtasks.  I do not want "Completion Date" on a subtask to be later that the "Completion Date" on it's parent issue.  How can I enforce this?  This should apply on when creating or editing the field.

For example, if IssueA Completion Date = 1-1-2021, then Completion Date on SubtaskA <= 1-1-2021.

Has anyone does this with Scriptrunner? Thanks.

[PD Sheehan · Accepted solution]

Create a behaviour configuration linked to your project and sub-task issue type.

Then add a server-side script on the Completion Date field.

import com.atlassian.jira.component.ComponentAccessor

def dateFormat = 'dd-MMM-yyy'
def dateFld = getFieldById(fieldChanged)
def dateValue = dateFld.value as Date
dateFld.clearError()
def parentIssueFld = getFieldById('parentIssueId')
if(parentIssueFld && parentIssueFld.value && dateValue){
   def parentIssue = ComponentAccessor.issueManager.getIssueObject(parentIssueFld.value as Long)
   def cf = ComponentAccessor.customFieldManager.getCustomFieldObject(dateFld.fieldId)
   def parentDate = parentIssue.getCustomFieldValue(cf) as Date
   if(parentDate && parentDate < dateValue){
      dateFld.setError("Subtask Date (${dateValue.format(dateFormat)}) cannot be after the date of parent issue (${parentDate.format(dateFormat)})")
   } 
}

[Inayat Nahvi]

Thanks @PD Sheehan !  This works perfectly.   Just one question about the logic on this line:

 if(parentDate && parentDate < dateValue){
      dateFld.setError("Subtask Date (${dateValue.format(dateFormat)}) cannot be after the date of parent issue (${parentDate.format(dateFormat)})")

Why does parentDate appear twice on this line?  Does this translate to if parentDate is present AND parentDate is less than Subtask Completion Date?

[PD Sheehan]

That is shorthand for 

if(parentDate != null){
  if(parentDate < DateValue){
     //do something
  }
}

with && the first term is evaluated ... if it is true, then the second term is evaluated.

This way, we don't try to compare a null date against a valid date. If the date is null, we exit the condition immediately.