Issue Summary

When using a cascading select list and using a post function to copy the value from the parent to a sub-task, errors are generated if the value in first list of the cascading field has no options in its second list.

Steps to Reproduce

1. Create a Select List (Cascading) custom field
2. Populate the first list with at least two options
3. On the first option, have at least one sub-option
4. On the second option, have no sub-options
5. Create a post function on the create transition to copy the value of that field to its sub-task
6. Create an issue with the second option selected
7. Create a sub-task
8. Experience the issue
9. Change the parent task to the first option
10. Successfully create a sub-task

Expected Results

A sub-task is created and the value(s) for the Select List (Cascade) are copied to the sub-task.

Actual Results

The sub-task is created, but errors are shown when trying to create the sub-task and the sub-task is visibility in the parent task depends upon whether new issue view is used or old issue view.

In new issue view:

• The sub-tasks are shown
• An error upon sub-task creation is shown though:

  We couldn't create the subtask
  Check your connection, then give it another try
  

In the old issue view:

• The sub-tasks are not shown
• An error upon creation is shown (despite the sub-task) being created:

  We can't create this issue for you right now, it could be due to unsupported content you've entered into one or more of the issue fields. If this situation persists, contact your administrator as they'll be able to access more specific information in the log file.
  

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available.