I'm trying to make a Date Formula field that display the next month in my record.
I got the object EntryLine__c where I display the year and month of my entry line.
Here is my formula :
IF(ISNULL(Year__c) || ISNULL(Month__c), DATE(YEAR(TODAY()),1,1), IF(Month__c = 12, DATE(Year__c + 1, 1, 1), DATE(Year__c, Month__c+1, 1)))
Year__c and Month__c are Numbers field. I'm testing if they are null because I don't want to have a null value in my formula. I'm using it in a time trigger and if it's null it will abort my Process Builder.
I tried with ISBLANK and ISNULL functions but it doesn't work. They're still evaluated to False even if my fields are empty. So I don't understand why it doesn't work.