fails:FileTest.zero? returns true if the file is empty
fails:FileTest.zero? returns false if the file is not empty
fails:FileTest.zero? returns true for NUL
fails:FileTest.zero? raises a TypeError if not passed a String type
fails:FileTest.zero? returns true inside a block opening a file if it is empty
fails:FileTest.zero? returns false for a directory
fails:FileTest.zero? returns false if the file does not exist
