JSON array undefined & empty in promise Bluebird

I am using Promise bluebird to process a json array objects from file. The problem arises if I want to store data in a json array (called list) and return this in the final process. The list is empty/undefined after the return of list or even in the final process. Running the code, I always have 1 value that is not false which trigger the adding/push of the json in the list.I am using Promise bluebird to process a json a