Right now the only test we have for dir() on _GenericAlias is

    def test_genericalias_dir(self):
        class Foo(Generic[T]):
            def bar(self):
                pass
            baz = 3
        # The class attributes of the original class should be visible even
        # in dir() of the GenericAlias. See bpo-45755.
        self.assertIn('bar', dir(Foo[int]))
        self.assertIn('baz', dir(Foo[int]))

And here's how it is defined:

We clearly need more tests:

1. That dunder methods are not included
2. What _GenericAlias API we expose (at least parts that we consider user-visible, like __args__ and __parameters__ and __origin__)
3. _GenericAlias has subclasses, they are also not tested

I will send a PR for this :)

Linked PRs

• gh-103395: Improve typing._GenericAlias.__dir__ coverage #103396
• [3.11] gh-103395: Improve typing._GenericAlias.__dir__ coverage (GH-103396) #103410