Error not being thrown on unsuccessful attempt

[istas]

I recently ran into the issue where the Less for the file I was trying to get JSON for was not compiling correctly on its own. It depended on some other files which were being imported correctly for our actual Less compilation. Since this file didn't compile alone it caused less2js to not create the file I wanted. But instead of throwing an error, the task failed silently and subsequent tasks used the previously compiled stale JSON.

Currently I am fixing this by deleting the previous JSON so that my tasks will error out if this file has not been created by less2js. But I think it would be good if less2js could be updated to throw an error if Less can't compile and to throw a warning or error when it is unable to create the JSON file.