Copying Mail Folders in Apple Mail

This is a bug I encountered in the process of supporting a CloudPull customer. I filed it as Radar 19512236.

Product: OS X

Classification: Serious Bug

Reproducibility: Always

Title: Copying Mail Folders in Apple Mail

Description: The ability to copy mail folders from one account to another in Apple Mail appears to be broken. The folder gets created in the destination account, but without that folder's messages.

Steps to Reproduce:
1. Configure Apple Mail with two IMAP accounts.
2. Select a folder from the source list under one account, and drag it to an area of the source list in the other account.

Expected Results:
I would expect that the folder and its messages are copied from the source account to the destination account.

Actual Results:
The folder is created in the destination account, but without any messages.

Configuration:
I see this using Gmail accounts as both the source and destination accounts. I also see this if the source account exists “On My Mac”.

Version & Build:
OS X 10.1.1 (14B25)

Additional Notes:
N/A.