Reuse packaging and its base classes

[pombredanne]

This error at https://dev.azure.com/nexB/2b40e32d-2a30-4c1b-b0f0-7fb807f657bb/_apis/build/builds/9618/logs/48

2023-01-15T17:07:54.5426090Z _________________________ test_api_with_specifier_pdt __________________________
2023-01-15T17:07:54.5427340Z [gw0] darwin -- Python 3.7.15 /Users/runner/work/1/s/venv/bin/python
2023-01-15T17:07:54.5427640Z 
2023-01-15T17:07:54.5428050Z     def test_api_with_specifier_pdt():
2023-01-15T17:07:54.5428530Z         result_file = test_env.get_temp_file("json")
2023-01-15T17:07:54.5429740Z         expected_file = test_env.get_test_loc("test-api-pdt-expected.json", must_exist=False)
2023-01-15T17:07:54.5430460Z         with open(result_file, "w") as result:
2023-01-15T17:07:54.5430880Z             result.write(
2023-01-15T17:07:54.5431290Z                 json.dumps(
2023-01-15T17:07:54.5431710Z                     resolver_api(
2023-01-15T17:07:54.5432490Z                         specifiers=["flask==2.1.2"],
2023-01-15T17:07:54.5433370Z                         python_version="3.10",
2023-01-15T17:07:54.5433870Z                         operating_system="linux",
2023-01-15T17:07:54.5434290Z >                       pdt_output=True,
2023-01-15T17:07:54.5435350Z                     ).to_dict()
2023-01-15T17:07:54.5435690Z                 )
2023-01-15T17:07:54.5436080Z             )
2023-01-15T17:07:54.5436210Z 
2023-01-15T17:07:54.5436610Z tests/test_api.py:55: 
2023-01-15T17:07:54.5437100Z _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
2023-01-15T17:07:54.5437660Z src/python_inspector/api.py:160: in resolve_dependencies
2023-01-15T17:07:54.5438300Z     dep = dependencies.get_dependency(specifier=specifier)
2023-01-15T17:07:54.5438890Z src/python_inspector/dependencies.py:69: in get_dependency
2023-01-15T17:07:54.5439390Z     requirement_line=specifier,
2023-01-15T17:07:54.5439940Z _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
2023-01-15T17:07:54.5440220Z 
2023-01-15T17:07:54.5441510Z self = <[AttributeError("'InstallRequirement' object has no attribute 'req'") raised in repr()] InstallRequirement object at 0x10f3de290>
2023-01-15T17:07:54.5442820Z req = <Requirement('flask==2.1.2')>, requirement_line = 'flask==2.1.2'
2023-01-15T17:07:54.5443510Z link = None, marker = None, install_options = None, global_options = None
2023-01-15T17:07:54.5444250Z hash_options = None, is_constraint = False, extras = (), invalid_options = None
2023-01-15T17:07:54.5444560Z 
2023-01-15T17:07:54.5444930Z     def __init__(
2023-01-15T17:07:54.5445260Z         self,
2023-01-15T17:07:54.5445640Z         req: Optional[Requirement],
2023-01-15T17:07:54.5446130Z         requirement_line: RequirementLine,
2023-01-15T17:07:54.5446590Z         link: Optional[Link] = None,
2023-01-15T17:07:54.5447030Z         marker: Optional[Marker] = None,
2023-01-15T17:07:54.5447490Z         install_options: Optional[List[str]] = None,
2023-01-15T17:07:54.5448060Z         global_options: Optional[List[str]] = None,
2023-01-15T17:07:54.5448570Z         hash_options: Optional[List[str]] = None,
2023-01-15T17:07:54.5449020Z         is_constraint: bool = False,
2023-01-15T17:07:54.5449500Z         extras: Collection[str] = (),
2023-01-15T17:07:54.5450030Z         invalid_options: Optional[Dict[str, Any]] = None,
2023-01-15T17:07:54.5450910Z     ) -> None:
2023-01-15T17:07:54.5451280Z         """
2023-01-15T17:07:54.5451720Z         Initialize a new pip requirement
2023-01-15T17:07:54.5452090Z     
2023-01-15T17:07:54.5453010Z         - ``req`` is a packaging Requirement object that may be None
2023-01-15T17:07:54.5454170Z         - ``requirement_line`` is the original line this requirement was found
2023-01-15T17:07:54.5455330Z         - ``link`` is a Link object provided when the requirement is a path or URL
2023-01-15T17:07:54.5456560Z         - ``marker`` is a packaging Marker object.
2023-01-15T17:07:54.5457160Z           This is provided when a marker is used and there is no ``req`` Requirement.
2023-01-15T17:07:54.5458380Z         - ``install_options``, ``global_options`` and ``hash_options`` are the
2023-01-15T17:07:54.5459550Z           CLI-style pip options for this specifc requirement.
2023-01-15T17:07:54.5460630Z         - ``is_constraint`` is True if this requirement came from loading a
2023-01-15T17:07:54.5461650Z            nested ``-c/--constraint`` file.
2023-01-15T17:07:54.5462740Z         - ``extras`` is a list of [extra] strings for this package.
2023-01-15T17:07:54.5463360Z            This is provided when extras are used and there is no ``req`` Requirement.
2023-01-15T17:07:54.5464690Z         - ``invalid_options`` are global pip options that are mistakenly set at the line-level.
2023-01-15T17:07:54.5465350Z            This is an error.
2023-01-15T17:07:54.5465690Z         """
2023-01-15T17:07:54.5466170Z >       assert req is None or isinstance(req, Requirement), req
2023-01-15T17:07:54.5467210Z E       AssertionError: <Requirement('flask==2.1.2')>
2023-01-15T17:07:54.5468660Z E       assert (<Requirement('flask==2.1.2')> is None or False)
2023-01-15T17:07:54.5470340Z E        +  where False = isinstance(<Requirement('flask==2.1.2')>, Requirement)
2023-01-15T17:07:54.5470670Z 
2023-01-15T17:07:54.5471700Z venv/lib/python3.7/site-packages/pip_requirements_parser.py:1970: AssertionError

is because packvers and packaging have different class hierarchies and it would be better to adopt a different approach.

• https://github.com/nexB/pip-requirements-parser/blob/main/src/packaging_legacy_version.py is a lightweight fork of packaging.version but it does not use the packaging.version base classes

• packvers is a hard fork of packaging and is therefore not using the packaging.version base classes and does not benefit of packaging updates.

None of these two approached is satisfying. We should go a different way, which would be making packavers a lightweight fork of packaging.version that WOULD USE the packaging.version base classes.

[benjamb]

Are you thinking something along the lines of: https://github.com/nexB/packvers/compare/main2...benjamb:packvers:base-classes?expand=1

Though perhaps even further stripped back.

[pombredanne]

@benjamb yes either something like this, or just extracting the LegacyVersion only and only provide support for this. packaging as evolved massively since this fork was done.