Add offsets to method#source_location
I would like to have byte offsets returned on the source_location for methods. For example:
b.source_location # => [file_name, line_number, start_byte, end_byte]
If we had the start and end byte for a method or proc, then we could find the source for methods and procs in each file. There are some cases (like with heredocuments) where the "end of the method" could be after the
end keyword. But I think if we just have offsets for the start of
def and the end of
end, I think it would cover 99% of usecases.