This mirrors logic in typing.get_args. The trickiness comes from how we
flatten args in collections.abc.Callable, see
https://bugs.python.org/issue42195
Copied from typing-extensions (python/typing#1054, python/typing#1120).
Documentation is intentionally omitted, so we can focus on getting the
runtime part in before the feature freeze.
Based on suggestions by Guido van Rossum, Spencer Brown, and Alex Waygood.
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Guido van Rossum <gvanrossum@gmail.com>
Co-authored-by: Ken Jin <kenjin4096@gmail.com>
I talked to @davidfstr and I offered to implement the runtime part of PEP 655
to make sure we can get it in before the feature freeze. We're going to defer
the documentation to a separate PR, because it can wait until after the feature
freeze.
The runtime implementation conveniently already exists in typing-extensions,
so I largely copied that.
Co-authored-by: David Foster <david@dafoster.net>
The goal here is to reduce potential confusion between
`assert_type(val, type)` and `assert isinstance(val, typ)`.
The former is meant to ask a type checker to confirm a fact, the latter
is meant to tell a type checker a fact. The behaviour of the latter more
closely resembles what I'd expect from the prior phrasing of
"assert [something] to the type checker".
Add methods __typing_subst__() in TypeVar and ParamSpec.
Simplify code by using more object-oriented approach, especially
the C code for types.GenericAlias and the Python code for
collections.abc.Callable.
GH-26091 added the _typevar_types and _paramspec_tvars instance
variables to _GenericAlias. However, they were not propagated
consistently. This commit addresses the most prominent deficiency
identified in bpo-46581 (namely their absence from
_GenericAlias.copy_with), but there could be others.
Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Co-authored-by: Alex Waygood <alex.waygood@gmail.com>
Co-authored-by: Nikita Sobolev <mail@sobolevn.me>
Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
This removes discrepancy between list["int"] and List["int"].
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
There are several changes:
1. We now don't explicitly check for any base / sub types, because new name check covers it
2. I've also checked that `no_type_check` do not modify foreign functions. It was the same as with `type`s
3. I've also covered `except TypeError` in `no_type_check` with a simple test case, it was not covered at all
4. I also felt like adding `lambda` test is a good idea: because `lambda` is a bit of both in class bodies: a function and an assignment
<!-- issue-number: [bpo-46571](https://bugs.python.org/issue46571) -->
https://bugs.python.org/issue46571
<!-- /issue-number -->
The `module` parameter carries semantic information about the forward ref.
Forward refs are different if they refer to different module even if they
have the same name. This affects the `__eq__`, `__repr__` and `__hash__` methods.
Co-authored-by: Andreas Hangauer <andreas.hangauer@siemens.com>
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
The module parameter carries semantic information about the forward ref.
Show to the user that forward refs with same argument but different
module are different.
Co-authored-by: Andreas Hangauer <andreas.hangauer@siemens.com>
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
* Substitution with a list of types returns now a tuple of types.
* Substitution with Concatenate returns now a Concatenate with
concatenated lists of arguments.
* Substitution with Ellipsis is not supported.
Previously this didn't matter because there weren't any valid code paths
that could trigger a type check with a special form, but after the bug
fix for `Annotated` wrapping special forms it's now possible to annotate
something like `Annotated['ClassVar[int]', (3, 4)]`. This change would
also be needed for proposed future changes, such as allowing `ClassVar`
and `Final` to nest each other in dataclasses.
We treat Annotated type arg as class-level annotation. This exempts it from checks against Final and ClassVar in order to allow using them in any nesting order.
Automerge-Triggered-By: GH:gvanrossum
For example Callable[P, T][[int], str, float] will now raise an error.
Use also term "arguments" instead of "parameters" in error
message for too few/many arguments.
This fixes TypedDict to work with get_type_hints and postponed evaluation of annotations across modules.
This is done by adding the module name to ForwardRef at the time the object is created and using that to resolve the globals during the evaluation.
Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
help(object) via pydoc.TextDoc.docclass(object) iterates over the
subclasses of object, which includes typing.io and typing.re if typing
is imported. It tries to access cls.__module__ for each of those
sub-classes. This change suppresses warnings when accessing
cls.__module__.
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 adds IO, TextIO, BinaryIO, Match, and Pattern.
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
Change class and module objects to lazy-create empty annotations dicts on demand. The annotations dicts are stored in the object's `__dict__` for backwards compatibility.
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).
Make the design more object-oriented.
Split _GenericAlias on two almost independent classes: for special
generic aliases like List and for parametrized generic aliases like List[int].
Add specialized subclasses for Callable, Callable[...], Tuple and Union[...].
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.
I tried to get rid of the `_ProtocolMeta`, but unfortunately it didn'y work. My idea to return a generic alias from `@runtime_checkable` made runtime protocols unpickleable. I am not sure what is worse (a custom metaclass or having some classes unpickleable), so I decided to stick with the status quo (since there were no complains so far). So essentially this is a copy of the implementation in `typing_extensions` with two modifications:
* Rename `@runtime` to `@runtime_checkable` (plus corresponding updates).
* Allow protocols that extend `collections.abc.Iterable` etc.
Matthew Rahtz
Samodya Abey
Shantanu
Serhiy Storchaka
Jelle Zijlstra
Adrian Garcia Badaracco
Gregory Beauregard
Matt Bogosian
James Hilton-Balfe
Niklas Rosenstein
Matt Bogosian
Nikita Sobolev
aha79
97littleleaf11
Zackery Spytz
Arie Bovenberg
Ken Jin
Alex Waygood
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Yurii Karabas
Bas van Beek
Hasan
Germán Méndez Bravo
Sebastian Rittau
will-ca
larryhastings
Pablo Galindo
Victor Stinner
Karthikeyan Singaravelan
Ross
Alex Grönholm
Mikhail Golubev
Batuhan Taskaya
Patrick Reader
Maggie Moss
Graham Bleaney
wyfo
Vlad Serebrennikov
Nickolena Fisher
HongWeipeng
Guido van Rossum
Raymond Hettinger
ananthan-123
Vlad Emelianov
Jakub Stasiak
Shantanu
Zac Hatfield-Dodds
benedwards14
HongWeipeng
plokmijnuhby
Divij Rajkumar
Ivan Levkivskyi
Anthony Sottile