Added two new attributes to ``_GenericAlias``:
* ``_typevar_types``, a single type or tuple of types indicating what types are treated as a ``TypeVar``. Used for ``isinstance`` checks.
* ``_paramspec_tvars ``, a boolean flag which guards special behavior for dealing with ``ParamSpec``. Setting it to ``True`` means this class deals with ``ParamSpec``.
Automerge-Triggered-By: GH:gvanrossum
This reverts commits 044a1048ca93d466965afc027b91a5a9eb9ce23c and 1be456ae9d53bb1cba2b24fc86175c282d1c2169, adapting the code to changes that happened after it.
Literal equality no longer depends on the order of arguments.
Fix issue related to `typing.Literal` caching by adding `typed` parameter to `typing._tp_cache` function.
Add deduplication of `typing.Literal` arguments.
This special marker annotation is intended to help in distinguishing
proper PEP 484-compliant type aliases from regular top-level variable
assignments.
The hard part was making all the tests pass; there are some subtle issues here, because apparently the future import wasn't tested very thoroughly in previous Python versions.
For example, `inspect.signature()` returned type objects normally (except for forward references), but strings with the future import. We changed it to try and return type objects by calling `typing.get_type_hints()`, but fall back on returning strings if that function fails (which it may do if there are future references in the annotations that require passing in a specific namespace to resolve).
This implements things like `list[int]`,
which returns an object of type `types.GenericAlias`.
This object mostly acts as a proxy for `list`,
but has attributes `__origin__` and `__args__`
that allow recovering the parts (with values `list` and `(int,)`.
There is also an approximate notion of type variables;
e.g. `list[T]` has a `__parameters__` attribute equal to `(T,)`.
Type variables are objects of type `typing.TypeVar`.
* bpo-39491: Merge PEP 593 (typing.Annotated) support
PEP 593 has been accepted some time ago. I got a green light for merging
this from Till, so I went ahead and combined the code contributed to
typing_extensions[1] and the documentation from the PEP 593 text[2].
My changes were limited to:
* removing code designed for typing_extensions to run on older Python
versions
* removing some irrelevant parts of the PEP text when copying it over as
documentation and otherwise changing few small bits to better serve
the purpose
* changing the get_type_hints signature to match reality (parameter
names)
I wasn't entirely sure how to go about crediting the authors but I used
my best judgment, let me know if something needs changing in this
regard.
[1] 8280de241f/typing_extensions/src_py3/typing_extensions.py
[2] 17710b8798/pep-0593.rst
This patch enables downstream projects inspecting a TypedDict subclass at runtime to tell which keys are optional.
This is essential for generating test data with Hypothesis or validating inputs with typeguard or pydantic.
This is an old feature request that appears from time to time. After a year of experimenting with various introspection capabilities in `typing_inspect` on PyPI, I propose to add these two most commonly used functions: `get_origin()` and `get_args()`. These are essentially thin public wrappers around private APIs: `__origin__` and `__args__`.
As discussed in the issue and on the typing tracker, exposing some public helpers instead of `__origin__` and `__args__` directly will give us more flexibility if we will decide to update the internal representation, while still maintaining backwards compatibility.
The implementation is very simple an is essentially a copy from `typing_inspect` with one exception: `ClassVar` was special-cased in `typing_inspect`, but I think this special-casing doesn't really help and only makes things more complicated.
