In a subsequent commit, we're going to start using `annotate-snippets`'s
functionality for diagnostic IDs in the rendering. As part of doing
that, I wanted to remove this special casing of an empty message. I did
that independently to see what, if anything, would change. (The changes
look fine to me. They'll be tweaked again in the next commit along with
a bunch of others.)
## Summary
Use a self-reference "marker" ~~and fixpoint iteration~~ to solve the
stack overflow problems with recursive protocols. This is not pretty and
somewhat tedious, but seems to work fine. Much better than all my
fixpoint-iteration attempts anyway.
closes https://github.com/astral-sh/ty/issues/93
## Test Plan
New Markdown tests.
## Summary
Add cycle handling for `try_metaclass` and `pep695_generic_context`
queries, as well as adjusting the cycle handling for `try_mro` to ensure
that it short-circuits on cycles and won't grow MROs indefinitely.
This reduces the number of failing fuzzer seeds from 68 to 17. The
latter count includes fuzzer seeds 120, 160, and 335, all of which
previously panicked but now either hang or are very slow; I've
temporarily skipped those seeds in the fuzzer until I can dig into that
slowness further.
This also allows us to move some more ecosystem projects from `bad.txt`
to `good.txt`, which I've done in
https://github.com/astral-sh/ruff/pull/17903
## Test Plan
Added mdtests.
@AlexWaygood pointed out that the `SliceLiteral` type variant was
originally created to handle slices before we had generics.
https://github.com/astral-sh/ruff/pull/17927#discussion_r2078115787
Now that we _do_ have generics, we can use a specialization of the
`slice` builtin type for slice literals.
This depends on https://github.com/astral-sh/ruff/pull/17956, since we
need to make sure that all typevar defaults are fully substituted when
specializing `slice`.
It's possible for a typevar to list another typevar as its default
value:
```py
class C[T, U = T]: ...
```
When specializing this class, if a type isn't provided for `U`, we would
previously use the default as-is, leaving an unspecialized `T` typevar
in the specialization. Instead, we want to use what `T` is mapped to as
the type of `U`.
```py
reveal_type(C()) # revealed: C[Unknown, Unknown]
reveal_type(C[int]()) # revealed: C[int, int]
reveal_type(C[int, str]()) # revealed: C[int, str]
```
This is especially important for the `slice` built-in type.
## Summary
This PR is a first step toward integration of the new `Diagnostic` type
into ruff. There are two main changes:
- A new `UnifiedFile` enum wrapping `File` for red-knot and a
`SourceFile` for ruff
- ruff's `Message::SyntaxError` variant is now a `Diagnostic` instead of
a `SyntaxErrorMessage`
The second of these changes was mostly just a proof of concept for the
first, and it went pretty smoothly. Converting `DiagnosticMessage`s will
be most of the work in replacing `Message` entirely.
## Test Plan
Existing tests, which show no changes.
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
Co-authored-by: Micha Reiser <micha@reiser.io>
Summary
--
This PR resolves both the typing-related and syntax error TODOs added in
#17563 by tracking a set of `global` bindings for each scope. As
discussed below, we avoid the additional AST traversal from ruff by
collecting `Name`s from `global` statements while building the semantic
index and emit a syntax error if the `Name` is already bound in the
current scope at the point of the `global` statement. This has the
downside of separating the error from the `SemanticSyntaxChecker`, but I
plan to explore using this approach in the `SemanticSyntaxChecker`
itself as a follow-up. It seems like this may be a better approach for
ruff as well.
Test Plan
--
Updated all of the related mdtests to remove the TODOs (and add quotes I
forgot on the messages).
There is one remaining TODO, but it requires `nonlocal` support, which
isn't even incorporated into the `SemanticSyntaxChecker` yet.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
Fixes: astral-sh/ty#159
This PR adds support for using `Self` in methods.
When the type of an annotation is `TypingSelf` it is converted to a type
var based on:
https://typing.python.org/en/latest/spec/generics.html#self
I just skipped Protocols because it had more problems and the tests was
not useful.
Also I need to create a follow up PR that implicitly assumes `self`
argument has type `Self`.
In order to infer the type in the `in_type_expression` method I needed
to have scope id and semantic index available. I used the idea from
[this PR](https://github.com/astral-sh/ruff/pull/17589/files) to pass
additional context to this method.
Also I think in all places that `in_type_expression` is called we need
to have this context because `Self` can be there so I didn't split the
method into one version with context and one without.
## Test Plan
Added new tests from spec.
---------
Co-authored-by: Micha Reiser <micha@reiser.io>
Co-authored-by: Carl Meyer <carl@astral.sh>
#17897 added variance handling for legacy typevars — but they were only
being considered when checking generic aliases of the same class:
```py
class A: ...
class B(A): ...
class C[T]: ...
static_assert(is_subtype_of(C[B], C[A]))
```
and not for generic subclasses:
```py
class D[U](C[U]): ...
static_assert(is_subtype_of(D[B], C[A]))
```
Now we check those too!
Closes https://github.com/astral-sh/ty/issues/101
Fixes#17867
## Summary
The CPython parser does not allow generator expressions which are the
sole arguments in an argument list to have a trailing comma.
With this change, we start flagging such instances.
## Test Plan
Added new inline tests.
## Summary
We now expect the client to send initialization options to opt-in to
experimental (but LSP-standardized) features, like completion support.
Specifically, the client should set `"experimental.completions.enable":
true`.
Closes https://github.com/astral-sh/ty/issues/74.
## Summary
This PR adds support for the `__all__` module variable.
Reference spec:
https://typing.python.org/en/latest/spec/distributing.html#library-interface-public-and-private-symbols
This PR adds a new `dunder_all_names` query that returns a set of
`Name`s defined in the `__all__` variable of the given `File`. The query
works by implementing the `StatementVisitor` and collects all the names
by recognizing the supported idioms as mentioned in the spec. Any idiom
that's not recognized are ignored.
The current implementation is minimum to what's required for us to
remove all the false positives that this is causing. Refer to the
"Follow-ups" section below to see what we can do next. I'll a open
separate issue to keep track of them.
Closes: astral-sh/ty#106Closes: astral-sh/ty#199
### Follow-ups
* Diagnostics:
* Add warning diagnostics for unrecognized `__all__` idioms, `__all__`
containing non-string element
* Add an error diagnostic for elements that are present in `__all__` but
not defined in the module. This could lead to runtime error
* Maybe we should return `<type>` instead of `Unknown | <type>` for
`module.__all__`. For example:
https://playknot.ruff.rs/2a6fe5d7-4e16-45b1-8ec3-d79f2d4ca894
* Mark a symbol that's mentioned in `__all__` as used otherwise it could
raise (possibly in the future) "unused-name" diagnostic
Supporting diagnostics will require that we update the return type of
the query to be something other than `Option<FxHashSet<Name>>`,
something that behaves like a result and provides a way to check whether
a name exists in `__all__`, loop over elements in `__all__`, loop over
the invalid elements, etc.
## Ecosystem analysis
The following are the maximum amount of diagnostics **removed** in the
ecosystem:
* "Type <module '...'> has no attribute ..."
* `collections.abc` - 14
* `numpy` - 35534
* `numpy.ma` - 296
* `numpy.char` - 37
* `numpy.testing` - 175
* `hashlib` - 311
* `scipy.fft` - 2
* `scipy.stats` - 38
* "Module '...' has no member ..."
* `collections.abc` - 85
* `numpy` - 508
* `numpy.testing` - 741
* `hashlib` - 36
* `scipy.stats` - 68
* `scipy.interpolate` - 7
* `scipy.signal` - 5
The following modules have dynamic `__all__` definition, so `ty` assumes
that `__all__` doesn't exists in that module:
* `scipy.stats`
(95a5d6ea8b/scipy/stats/__init__.py (L665))
* `scipy.interpolate`
(95a5d6ea8b/scipy/interpolate/__init__.py (L221))
* `scipy.signal` (indirectly via
95a5d6ea8b/scipy/signal/_signal_api.py (L30))
* `numpy.testing`
(de784cd6ee/numpy/testing/__init__.py (L16-L18))
~There's this one category of **false positives** that have been added:~
Fixed the false positives by also ignoring `__all__` from a module that
uses unrecognized idioms.
<details><summary>Details about the false postivie:</summary>
<p>
The `scipy.stats` module has dynamic `__all__` and it imports a bunch of
symbols via star imports. Some of those modules have a mix of valid and
invalid `__all__` idioms. For example, in
95a5d6ea8b/scipy/stats/distributions.py (L18-L24),
2 out of 4 `__all__` idioms are invalid but currently `ty` recognizes
two of them and says that the module has a `__all__` with 5 values. This
leads to around **2055** newly added false positives of the form:
```
Type <module 'scipy.stats'> has no attribute ...
```
I think the fix here is to completely ignore `__all__`, not only if
there are invalid elements in it, but also if there are unrecognized
idioms used in the module.
</p>
</details>
## Test Plan
Add a bunch of test cases using the new `ty_extensions.dunder_all_names`
function to extract a module's `__all__` names.
Update various test cases to remove false positives around `*` imports
and re-export convention.
Add new test cases for named import behavior as `*` imports covers all
of it already (thanks Alex!).
## Summary
Fixes#17541
Before this change, in the case of overloaded functions,
`@dataclass_transform` was detected only when applied to the
implementation, not the overloads.
However, the spec also allows this decorator to be applied to any of the
overloads as well.
With this PR, we start handling `@dataclass_transform`s applied to
overloads.
## Test Plan
Fixed existing TODOs in the test suite.
## Summary
This is sort of an anticlimactic resolution to #17863, but now that we
understand what the root cause for the stack overflows was, I think it's
fine to enable running on this project. See the linked ticket for the
full analysis.
closes#17863
## Test Plan
Ran lots of times locally and never observed a crash at worker thread
stack sizes > 8 MiB.
We now track the variance of each typevar, and obey the `covariant` and
`contravariant` parameters to the legacy `TypeVar` constructor. We still
don't yet infer variance for PEP-695 typevars or for the
`infer_variance` legacy constructor parameter.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
A recursive protocol like the following would previously lead to stack
overflows when attempting to create the union type for the `P | None`
member, because `UnionBuilder` checks if element types are fully static,
and the fully-static check on `P` would in turn list all members and
check whether all of them were fully static, leading to a cycle.
```py
from __future__ import annotations
from typing import Protocol
class P(Protocol):
parent: P | None
```
Here, we make the fully-static check on protocols a salsa query and add
fixpoint iteration, starting with `true` as the initial value (assume
that the recursive protocol is fully-static). If the recursive protocol
has any non-fully-static members, we still return `false` when
re-executing the query (see newly added tests).
closes#17861
## Test Plan
Added regression test
## Summary
Resolves#15502.
`ty generate-shell-completion` now works in a similar manner to `ruff
generate-shell-completion`.
## Test Plan
Manually:
<details>
```shell
$ cargo run --package ty generate-shell-completion nushell
module completions {
# An extremely fast Python type checker.
export extern ty [
--help(-h) # Print help
--version(-V) # Print version
]
# ...
}
export use completions *
```
</details>
@AlexWaygood discovered that even though we've been propagating
specializations to _parent_ base classes correctly, we haven't been
passing them on to _grandparent_ base classes:
https://github.com/astral-sh/ruff/pull/17832#issuecomment-2854360969
```py
class Bar[T]:
x: T
class Baz[T](Bar[T]): ...
class Spam[T](Baz[T]): ...
reveal_type(Spam[int]().x) # revealed: `T`, but should be `int`
```
This PR updates the MRO machinery to apply the current specialization
when starting to iterate the MRO of each base class.
## Summary
This PR partially addresses #16418 via the following:
- `LinterSettings::unresolved_python_version` is now a `TargetVersion`,
which is a thin wrapper around an `Option<PythonVersion>`
- `Checker::target_version` now calls `TargetVersion::linter_version`
internally, which in turn uses `unwrap_or_default` to preserve the
current default behavior
- Calls to the parser now call `TargetVersion::parser_version`, which
calls `unwrap_or_else(PythonVersion::latest)`
- The `Checker`'s implementation of
`SemanticSyntaxContext::python_version` also uses
`TargetVersion::parser_version` to use `PythonVersion::latest` for
semantic errors
In short, all lint rule behavior should be unchanged, but we default to
the latest Python version for the new syntax errors, which should
minimize confusing version-related syntax errors for users without a
version configured.
## Test Plan
Existing tests, which showed no changes (except for printing default
settings).
## Summary
Introducing a new rule based on discussions in #15732 and #15729 that
checks for unnecessary in with empty collections.
I called it in_empty_collection and gave the rule number RUF060.
Rule is in preview group.
e.g.,
```
❯ uv run -q -- ty -V
ty 0.0.0-alpha.4 (08881edba 2025-05-05)
❯ uv run -q -- ty --version
ty 0.0.0-alpha.4 (08881edba 2025-05-05)
```
Previously, this just displayed `ty 0.0.0` because it didn't use our
custom version implementation. We no longer have a short version —
matching the interface in uv. We could add a variant for it, if it seems
important to people. However, I think we found it more confusing than
not over there and didn't get any complaints about the change.
Closes https://github.com/astral-sh/ty/issues/54
Extends https://github.com/astral-sh/ruff/pull/17866, using
`dist-workspace.toml` as a source of truth for versions to enable
version retrieval in distributions that are not Git repositories (i.e.,
Python source distributions and source tarballs consumed by Linux
distros).
I retain the Git tag lookup from
https://github.com/astral-sh/ruff/pull/17866 as a fallback — it seems
harmless, but we could drop it to simplify things here.
I confirmed this works from the repository as well as Python source and
binary distributions:
```
❯ uv run --refresh-package ty --reinstall-package ty -q -- ty version
ty 0.0.1-alpha.1+5 (2eadc9e61 2025-05-05)
❯ uv build
...
❯ uvx --from ty@dist/ty-0.0.0a1.tar.gz --no-cache -q -- ty version
ty 0.0.1-alpha.1
❯ uvx --from ty@dist/ty-0.0.0a1-py3-none-macosx_11_0_arm64.whl -q -- ty version
ty 0.0.1-alpha.1
```
Requires https://github.com/astral-sh/ty/pull/36
cc @Gankra and @MichaReiser for review.
Currently, `ty version` pulls its information from the Ruff repository —
but we want this to pull from the repository in the directory _above_
when Ruff is a submodule.
I tested this in the `ty` repository after tagging an arbitrary commit:
```
❯ uv run --refresh-package ty --reinstall-package ty ty version
Built ty @ file:///Users/zb/workspace/ty
Uninstalled 1 package in 2ms
Installed 1 package in 1ms
ty 0.0.0+3 (34253b1d4 2025-05-05)
```
We also use the last Git tag as the source of truth for the version,
instead of the crate version. However, we'll need a way to set the
version for releases still, as the tag is published _after_ the build.
We can either tag early (without pushing the tag to the remote), or add
another environment variable. (**Note, this approach is changed in a
follow-up. See https://github.com/astral-sh/ruff/pull/17868**)
From this repository, the version will be `unknown`:
```
❯ cargo run -q --bin ty -- version
ty unknown
```
We could add special handling like... `ty unknown (ruff@...)` but I see
that as a secondary goal.
Closes https://github.com/astral-sh/ty/issues/5
The reviewer situation in this repository is unhinged, cc @Gankra and
@MichaReiser for review.
## Summary
This fixes some false positives that showed up in the primer diff for
https://github.com/astral-sh/ruff/pull/17832
## Test Plan
new mdtests added that fail with false-positive diagnostics on `main`
## Summary
This PR fixes#17595.
## Test Plan
New test cases are added to `mdtest/narrow/conditionals/nested.md`.
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
If a typevar is declared as having a default, we shouldn't require a
type to be specified for that typevar when explicitly specializing a
generic class:
```py
class WithDefault[T, U = int]: ...
reveal_type(WithDefault[str]()) # revealed: WithDefault[str, int]
```
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Fixes
https://github.com/astral-sh/ruff/pull/17832#issuecomment-2851224968. We
had a comment that we did not need to apply specializations to generic
aliases, or to the bound `self` of a bound method, because they were
already specialized. But they might be specialized with a type variable,
which _does_ need to be specialized, in the case of a "multi-step"
specialization, such as:
```py
class LinkedList[T]: ...
class C[U]:
def method(self) -> LinkedList[U]:
return LinkedList[U]()
```
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
closes#17472
This is obviously just a band-aid solution to this problem (in that you
can always make your [pathological
inputs](28994edd82/sympy/polys/numberfields/resolvent_lookup.py)
bigger and it will still crash), but I think this is not an unreasonable
change — even if we add more sophisticated solutions later. I tried
using `stacker` as suggested by @MichaReiser, and it works. But it's
unclear where exactly would be the right place to put it, and even for
the `sympy` problem, we would need to add it both in the semantic index
builder AST traversal and in type inference. Increasing the default
stack size for worker threads, as proposed here, doesn't solve the
underlying problem (that there is a hard limit), but it is more
universal in the sense that it is not specific to large binary-operator
expression chains.
To determine a reasonable stack size, I created files that look like
*right associative*:
```py
from typing import reveal_type
total = (1 + (1 + (1 + (1 + (… + 1)))))
reveal_type(total)
```
*left associative*
```py
from typing import reveal_type
total = 1 + 1 + 1 + 1 + … + 1
reveal_type(total)
```
with a variable amount of operands (`N`). I then chose the stack size
large enough to still be able to handle cases that existing type
checkers can not:
```
right
N = 20: mypy takes ~ 1min
N = 350: pyright crashes with a stack overflow (mypy fails with "too many nested parentheses")
N = 800: ty(main) infers Literal[800] instantly
N = 1000: ty(main) crashes with "thread '<unknown>' has overflowed its stack"
N = 7000: ty(this branch) infers Literal[7000] instantly
N = 8000+: ty(this branch) crashes
left
N = 300: pyright emits "Maximum parse depth exceeded; break expression into smaller sub-expressions"
total is inferred as Unknown
N = 5500: mypy crashes with "INTERNAL ERROR"
N = 2500: ty(main) infers Literal[2500] instantly
N = 3000: ty(main) crashes with "thread '<unknown>' has overflowed its stack"
N = 22000: ty(this branch) infers Literal[22000] instantly
N = 23000+: ty(this branch) crashes
```
## Test Plan
New regression test.
This fixes cycle panics in several ecosystem projects (moved to
`good.txt` in a following PR
https://github.com/astral-sh/ruff/pull/17834 because our mypy-primer job
doesn't handle it well if we move projects to `good.txt` in the same PR
that fixes `ty` to handle them), as well as in the minimal case in the
added mdtest. It also fixes a number of panicking fuzzer seeds. It
doesn't appear to cause any regression in any ecosystem project or any
fuzzer seed.
The PR add the fix safety section for rule `RUF013`
(https://github.com/astral-sh/ruff/issues/15584 )
The fix was introduced here #4831
The rule as a lot of False Negative (as it is explained in the docs of
the rule).
The main reason because the fix is unsafe is that it could change code
generation tools behaviour, as in the example here:
```python
def generate_api_docs(func):
hints = get_type_hints(func)
for param, hint in hints.items():
if is_optional_type(hint):
print(f"Parameter '{param}' is optional")
else:
print(f"Parameter '{param}' is required")
# Before fix
def create_user(name: str, roles: list[str] = None):
pass
# After fix
def create_user(name: str, roles: Optional[list[str]] = None):
pass
# Generated docs would change from "roles is required" to "roles is optional"
```
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Re: #17526
## Summary
Add test fixtures for `AwaitOutsideAsync` and
`AsyncComprehensionOutsideAsyncFunction` errors.
<!-- What's the purpose of the change? What does it do, and why? -->
## Test Plan
This is a test.
<!-- How was it tested? -->
Re: #17526
## Summary
Add integration tests for Python Semantic Syntax for
`InvalidStarExpression`, `DuplicateMatchKey`, and
`DuplicateMatchClassAttribute`.
## Note
- Red knot integration tests for `DuplicateMatchKey` exist already in
line 89-101.
<!-- What's the purpose of the change? What does it do, and why? -->
## Test Plan
This is a test.
<!-- How was it tested? -->
When attempting to determine whether `import foo.bar.baz` is a known
first-party import relative to [user-provided source
paths](https://docs.astral.sh/ruff/settings/#src), when `preview` is
enabled we now check that `SRC/foo/bar/baz` is a directory or
`SRC/foo/bar/baz.py` or `SRC/foo/bar/baz.pyi` exist.
Previously, we just checked the analogous thing for `SRC/foo`, but this
can be misleading in situations with disjoint namespace packages that
share a common base name (e.g. we may be working inside the namespace
package `foo.buzz` and importing `foo.bar` from elsewhere).
Supersedes #12987Closes#12984
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## Summary
Fixes#17798
<!-- What's the purpose of the change? What does it do, and why? -->
## Test Plan
Snapshot tests
<!-- How was it tested? -->
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Skip attribute check in try catch block (`AIR301`)
## Test Plan
<!-- How was it tested? -->
update
`crates/ruff_linter/resources/test/fixtures/airflow/AIR301_names_try.py`
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Remove `airflow.utils.dag_parsing_context.get_parsing_context` from
AIR301 as it has been moved to AIR311
## Test Plan
<!-- How was it tested? -->
the test fixture was updated in the previous PR
## Summary
When entering an `infer_expression_types` cycle from
`TypeInferenceBuilder::infer_standalone_expression`, we might get back a
`TypeInference::cycle_fallback(…)` that doesn't actually contain any new
types, but instead it contains a `cycle_fallback_type` which is set to
`Some(Type::Never)`. When calling `self.extend(…)`, we therefore don't
really pull in a type for the expression we're interested in. This
caused us to panic if we tried to call `self.expression_type(…)` after
`self.extend(…)`.
The proposed fix here is to retrieve that type from the nested
`TypeInferenceBuilder` directly, which will correctly fall back to
`cycle_fallback_type`.
## Details
I minimized the second example from #17792 a bit further and used this
example for debugging:
```py
from __future__ import annotations
class C: ...
def f(arg: C):
pass
x, _ = f(1)
assert x
```
This is self-referential because when we check the assignment statement
`x, _ = f(1)`, we need to look up the signature of `f`. Since evaluation
of annotations is deferred, we look up the public type of `C` for the
`arg` parameter. The public use of `C` is visibility-constraint by "`x`"
via the `assert` statement. While evaluating this constraint, we need to
look up the type of `x`, which in turn leads us back to the `x, _ =
f(1)` definition.
The reason why this only showed up in the relatively peculiar case with
unpack assignments is the code here:
78b4c3ccf1/crates/ty_python_semantic/src/types/infer.rs (L2709-L2718)
For a non-unpack assignment like `x = f(1)`, we would not try to infer
the right-hand side eagerly. Instead, we would enter a
`infer_definition_types` cycle that handles the situation correctly. For
unpack assignments, however, we try to infer the type of `value`
(`f(1)`) and therefore enter the cycle via `standalone_expression_type
=> infer_expression_type`.
closes#17792
## Test Plan
* New regression test
* Made sure that we can now run successfully on scipy => see #17850
This PR updates the semantic model for Python 3.14 by essentially
equating "run using Python 3.14" with "uses `from __future__ import
annotations`".
While this is not technically correct under the hood, it appears to be
correct for the purposes of our semantic model. That is: from the point
of view of deciding when to parse, bind, etc. annotations, these two
contexts behave the same. More generally these contexts behave the same
unless you are performing some kind of introspection like the following:
Without future import:
```pycon
>>> from annotationlib import get_annotations,Format
>>> def foo()->Bar:...
...
>>> get_annotations(foo,format=Format.FORWARDREF)
{'return': ForwardRef('Bar')}
>>> get_annotations(foo,format=Format.STRING)
{'return': 'Bar'}
>>> get_annotations(foo,format=Format.VALUE)
Traceback (most recent call last):
[...]
NameError: name 'Bar' is not defined
>>> get_annotations(foo)
Traceback (most recent call last):
[...]
NameError: name 'Bar' is not defined
```
With future import:
```
>>> from __future__ import annotations
>>> from annotationlib import get_annotations,Format
>>> def foo()->Bar:...
...
>>> get_annotations(foo,format=Format.FORWARDREF)
{'return': 'Bar'}
>>> get_annotations(foo,format=Format.STRING)
{'return': 'Bar'}
>>> get_annotations(foo,format=Format.VALUE)
{'return': 'Bar'}
>>> get_annotations(foo)
{'return': 'Bar'}
```
(Note: the result of the last call to `get_annotations` in these
examples relies on the fact that, as of this writing, the default value
for `format` is `Format.VALUE`).
If one day we support lint rules targeting code that introspects using
the new `annotationlib`, then it is possible we will need to revisit our
approximation.
Closes#15100
## Summary
Currently red-knot does not understand `Foo` and `Bar` here as being
equivalent:
```py
from typing import Protocol
class A: ...
class B: ...
class C: ...
class Foo(Protocol):
x: A | B | C
class Bar(Protocol):
x: B | A | C
```
Nor does it understand `A | B | Foo` as being equivalent to `Bar | B |
A`. This PR fixes that.
## Test Plan
new mdtest assertions added that fail on `main`
## Summary
Currently this assertion fails on `main`, because we do not synthesize a
`__call__` attribute for Callable types:
```py
from typing import Protocol, Callable
from knot_extensions import static_assert, is_assignable_to
class Foo(Protocol):
def __call__(self, x: int, /) -> str: ...
static_assert(is_assignable_to(Callable[[int], str], Foo))
```
This PR fixes that.
See previous discussion about this in
https://github.com/astral-sh/ruff/pull/16493#discussion_r1985098508 and
https://github.com/astral-sh/ruff/pull/17682#issuecomment-2839527750
## Test Plan
Existing mdtests updated; a couple of new ones added.