fix: qualifiers type annotation

[jhoward-lm]

This PR modifies the type annotation of the qualifiers attribute declaration from:

qualifiers: Union[str, Dict[str, str], None]

to:

qualifiers: Dict[str, str]

in order to reflect its true runtime type.

Closes #169.

Miscellaneous

• fixed return type of the encode: "Optional[Literal[False]]" overload of normalize_qualifiers to Dict[str, str]
• fixed return type of the encode: "Optional[Literal[False]]" overload of normalize to Dict[str, str] (the other tuple members in the return type unchanged)
• updated instances of Union[AnyStr, Dict[str, str], None] to Optional[Union[AnyStr, Dict[str, str]]]
• updated instances of Union[str, Dict[str, str], None] to Optional[Union[str, Dict[str, str]]]
• removed unused # NOQA directives
• updated return type of PackageURL.__new__ and PackageURL.from_string to typing_extensions.Self
• updated first param name of PackageURL.__new__ from self to cls since it is a classmethod
• removed quotes from type annotation forward references by adding from __future__ import annotations

[jhoward-lm]

@tdruez @gruebel I don't have permissions to add reviewers, please take a look when you get a chance. Thanks!

[gruebel]

looks good and locally it passes mypy 😄

[tdruez]

@jhoward-lm I see there are still Union[str, Dict[str, str], None] references in the source, should those be updated to Dict[str, str] as well?

[jhoward-lm]

@tdruez I don't believe so. Those are generalized argument/parameter types, but the type gets narrowed before returning.

You did however draw my attention to several other typing issues; I'll push a commit shortly for review

[jhoward-lm]

@tdruez @gruebel With my most recent comment, tests still pass locally, although the oldest version of python I was able to test with was 3.9 (3.7 and 3.8 are EOL so I couldn't install them with homebrew).

I'll update the PR description with more detail. Let me know your thoughts!

[gruebel]

you can easily fix this, then I don't need to create a separate PR 😅

Just create your own AnyStr type alias and remove the one coming from the typing module.

Add

AnyStr = Union[str, bytes]

directly under basestring at the top and remove the from typing import AnyStr. AnyStr was deprecated in Python 3.13 anyway.

[jhoward-lm]

Good call! One small alteration: since it's only used for type hints, I put it into the TYPE_CHECKING block. Tests still pass locally. Are you good with that?

[gruebel]

sure, also sounds good

[jhoward-lm]

@gruebel @tdruez
With the addition of from __future__ import annotations, the pipe style union operator as well as built-in collection types (Dict -> dict, Tuple -> tuple, etc.) are available. I verified by running pyupgrade --py37-plus src/packageurl/__init__.py.

So things like this could be updated across the board:

# before
Union[str, Dict[str, str], None]

# after
str | dict[str, str] | None

Let me know if you want me to go ahead with it, or I can hold off.

[gruebel]

I actually like the newer syntax style more than the old one, but I would recommend to do it in a follow-up PR, because it is kind of like formatting and I don't like to mix actual changes with formatting.