Built in Script Transformation window throws a 500 when checking the code in the script window.

• Log into a confluence 6.15 instance with the latest SR version installed. (5.5.2-SNAPSHOT)
• Navigate to the Built-in-https://productsupport.adaptavist.com/browse/SRCONF-666#Scripts page and select the Rename pages script.
• Using the examples below the transformation window, copy one of the code examples so it populates the transformation code window. 
• You will see a spinner toward the bottom right of the window that continuously spins and a 500 Internal Server Error shown on the console. 

VM51862:1 POST http://localhost:8080/confluence/rest/scriptrunner/latest/codeinsight/check 500 (Internal Server Error)

Seems like a typescript issue. 

If the code is correct, it will still work as normal which is why this is a low priority.