Incorect "usage" argument order for github backend

[Prinzhorn]

First time user here. I was finally able to successfully export GitHub data, thanks!

perceval github --help gives

usage: perceval [-h] [--category CATEGORY] [--tag TAG] [--filter-classified] [--from-date FROM_DATE] [--to-date TO_DATE] [--archive-path ARCHIVE_PATH] [--no-archive] [--fetch-archive]
                [--archived-since ARCHIVED_SINCE] [--no-ssl-verify] [-o OUTFILE] [--json-line] [--enterprise-url BASE_URL] [--sleep-for-rate] [--min-rate-to-sleep MIN_RATE_TO_SLEEP] [-t API_TOKEN [API_TOKEN ...]]
                [--github-app-id GITHUB_APP_ID] [--github-app-pk-filepath GITHUB_APP_PK_FILEPATH] [--max-items MAX_ITEMS] [--max-retries MAX_RETRIES] [--sleep-time SLEEP_TIME]
                owner repository

but it's actually

usage: perceval github owner repository [-h] [--category CATEGORY] [--tag TAG] [--filter-classified] [--from-date FROM_DATE] [--to-date TO_DATE] [--archive-path ARCHIVE_PATH] [--no-archive] [--fetch-archive]
                [--archived-since ARCHIVED_SINCE] [--no-ssl-verify] [-o OUTFILE] [--json-line] [--enterprise-url BASE_URL] [--sleep-for-rate] [--min-rate-to-sleep MIN_RATE_TO_SLEEP] [-t API_TOKEN [API_TOKEN ...]]
                [--github-app-id GITHUB_APP_ID] [--github-app-pk-filepath GITHUB_APP_PK_FILEPATH] [--max-items MAX_ITEMS] [--max-retries MAX_RETRIES] [--sleep-time SLEEP_TIME]

1. It doesn't have the backend in the usage
2. It has "owner repository" at the end, but they need to appear before the other arguments (it does list "positional arguments" first in the text that follows)

Maybe this is some weird standard way to output the usage, but I found it confusing and I think this would be better if it were in the correct order and included the backend in the usage.

[sduenas]

You are right. This is a bug. Thanks for reporting it. It's the same behaviour with the other backeds too.

[vchrombie]

Hi

1. It doesn't have the backend in the usage

I fixed this by setting the prog correctly.

2. It has "owner repository" at the end, but they need to appear before the other arguments (it does list "positional arguments" first in the text that follows)

The order of arguments in the help/usage seems to be automatically generated by the argparse library, and enforcing a fixed order, particularly for positional arguments, might not be straightforward. Do you have any thoughts on this? @sduenas

$ perceval github -h
[2024-08-12 17:58:47,081] - Sir Perceval is on his quest.
usage: perceval github [-h] [--category CATEGORY] [--tag TAG] [--filter-classified] [--from-date FROM_DATE] [--to-date TO_DATE] [--archive-path ARCHIVE_PATH] [--no-archive] [--fetch-archive]
                       [--archived-since ARCHIVED_SINCE] [--no-ssl-verify] [-o OUTFILE] [--json-line] [--enterprise-url BASE_URL] [--sleep-for-rate] [--min-rate-to-sleep MIN_RATE_TO_SLEEP]
                       [-t API_TOKEN [API_TOKEN ...]] [--github-app-id GITHUB_APP_ID] [--github-app-pk-filepath GITHUB_APP_PK_FILEPATH] [--max-items MAX_ITEMS] [--max-retries MAX_RETRIES]
                       [--sleep-time SLEEP_TIME]
                       owner repository

positional arguments:
  owner                 GitHub owner
  repository            GitHub repository

optional arguments:
  -h, --help            show this help message and exit
  
  . . .
  . . .

[vchrombie]

The order of arguments in the help/usage seems to be automatically generated by the argparse library, and enforcing a fixed order, particularly for positional arguments, might not be straightforward.

Initially, it seemed that because GitHubCommand extends BackendCommand, the arguments defined in the constructor appeared first in the help message and then the backend specific positional arguments. However, it turns out that no matter the order in which the arguments are defined in the code, argparse automatically lists positional arguments at the end of the usage message but ensures they appear first in the description and during actual command execution.

Here is a small POC

import argparse

parser = argparse.ArgumentParser()
parser.add_argument('x', type=int, help='first value')
parser.add_argument('-f', type=int, help='second value')
args = parser.parse_args()

$ python script.py -h
usage: script.py [-h] [-f F] x

positional arguments:
  x           first value

optional arguments:
  -h, --help  show this help message and exit
  -f F        second value