Total Parser function skipped if the value is ''

[daniel-butler]

I love this package! It saved me a ton of time!

Given a bai2 file like the one below, a stripped down example of a real bai2 generated by a the bank when accounts in the group were closed:

from bai2 import bai2

bai2_string = """01,1111,testcompany,210101,0101,010101010101,,,2/
02,testcompany,1111,1,210101,2359,,2/
03,12345,/
49,,2/
03,54321,/
49,,2/
98,0,2,6/
99,0,1,8/
"""
bai2_file = bai2.parse_from_string(bai2_string)

The problem is the Account Trailer records. Because the Summary Total value is blank when running this as is it results in the following error: bai2.exceptions.IntegrityException: Invalid account control total for Account. expected None, found 0

When implementing a simple int parser that looks for '' and returns 0 instead...

def parse_int(value) -> int:
    return int(value) if value else 0

...then updating the AccountTrailerParser fields_config to use the parser

class AccountTrailerParser(BaseSingleParser):
    model = AccountTrailer

    fields_config = [
        ('account_control_total', parse_int),
        ('number_of_records', int)
    ]

The same error is raised because the BaseSingleParsers _parse_field_from_config will skip the parsing function if the value is ''

It happens here:

    def _parse_field_from_config(self, field_config, raw_value):
        if isinstance(field_config, str):
            field_config = (field_config, lambda x: x)

        field_name, parser = field_config
        field_value = parser(raw_value) if raw_value else None   # <----
        return field_name, field_value

I see a few options:

1. Add a catch for an int parser on total fields
2. get rid of the '' catch then implement parsing functions to handle '' values themselves
3. Adding extra options to the parse model config to know if the None catch should be skipped
4. Something else?

I am going to send a pull request with #1 but I'm open to suggestions

[daniel-butler]

When creating the pull request I found removing the if raw_value else None broke other fields that were not expecting a 0. The pull request was updated to add a guard for total fields when the parser is an int.