Bump jsonschema to 4.19.*

[srittau]

Closes: #10417

[srittau]

Depends on typeshed-internal/stub_uploader#100.

[srittau]

I think this is the first package where a dependency doesn't work with all Python versions we support. I guess we need a new METADATA.toml field minimum_python_version or similar.

[AlexWaygood]

I think this is the first package where a dependency doesn't work with all Python versions we support. I guess we need a new METADATA.toml field minimum_python_version or similar.

New versions of numpy don't support Python 3.7, which is why we run mypy_test.py on Python 3.7 these days, rather than just with --python-version 3.7. In theory, pip should notice that we're using Python 3.7, and refuse to install a version of the package that declares it needs Python 3.8 or higher. This works fine when testing types-tensorflow, which has a dependency on numpy; mypy_test.py just installs a very old version of numpy into the dynamically created venv when testing types-tensorflow, a version of numpy that still supports Python 3.7.

So I'm curious to see exactly what the issue is here...

[srittau]

I assume (not investigated yet) that referencing doesn't declare a dependency on python >= 3.8.

[AlexWaygood]

I'm looking at it

[AlexWaygood]

Maybe we should print this to the terminal when the test fails even if the --verbose flag isn't specified for mypy_test.py. It's pretty hard to figure out why things are failing in cases like this without it:

typeshed/tests/mypy_test.py

Lines 299 to 302 in 54193d5

	if non_types_dependencies and args.verbose:
	print("Ran with the following environment:")
	subprocess.run([venv_info.pip_exe, "freeze", "--all"])
	print()

[AlexWaygood]

Okay, so it's installing referencing==0.8.9 in CI on Python 3.7 (not the latest version of referencing -- the latest version is referencing==0.30.2, and the latest version does indeed declare that it only supports Python 3.8+).

[AlexWaygood]

And, yup, referencing==0.8.9 is incompatible with Python 3.7, despite the fact that it has no requires-python = ">=3.8" marker in its pyproject.toml file yet (that was only added in later versions). The issue is this function here: https://github.com/python-jsonschema/referencing/blob/a37d9049ce9c78291b7e716f764a7d9790667ed6/referencing/_core.py#L181-L189

    def resource_at(
        self,
        uri: str,
    ) -> tuple[IdentifiedResource, PMap[str, AnchorType], Registry]:
        at_uri = self._contents.get(uri)
        if at_uri is None or uri in self._uncrawled:
            registry = self._crawl()
            return *registry._contents[uri], registry
        return *at_uri, self

Those return statements parse as valid syntax on Python 3.8, but not 3.7.

[AlexWaygood]

I guess we need a new METADATA.toml field minimum_python_version or similar.

We should be able to merge #10559 as soon as the PyPI admins let mypy publish a 1.5 patch release fixing the stubtest regression. (Or we could just allowlist the stubtest regression for now, and unallowlist it as soon as mypy 1.5.1 comes out.) Once #10559 is merged, we stop running mypy_test.py on Python 3.7, so the problem sort-of becomes moot.

We're only in this situation in the first place because the referencing didn't dot all the I's in its packaging metadata for its early releases, so it feels unlikely it'll come up too much.

[AlexWaygood]

We unfortunately can't pin to any version of referencing earlier than v0.8.9 (even if they're compatible with Python 3.7, which I haven't checked), since v0.8.9 is the first version of referencing that has a py.typed marker.

[srittau]

Thanks for the analysis! Let's wait for mypy 1.5 then and see if that helps.

[github-actions]

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉