Commit Graph

1062 Commits

Author SHA1 Message Date
Douglas Creager
d88120b187 mark these as TODO 2025-12-02 14:46:29 -05:00
Douglas Creager
2b949b3e67 Merge remote-tracking branch 'origin/main' into dcreager/callable-return
* origin/main: (67 commits)
  Move `Token`, `TokenKind` and `Tokens` to `ruff-python-ast` (#21760)
  [ty] Don't confuse multiple occurrences of `typing.Self` when binding bound methods (#21754)
  Use our org-wide Renovate preset (#21759)
  Delete `my-script.py` (#21751)
  [ty] Move `all_members`, and related types/routines, out of `ide_support.rs` (#21695)
  [ty] Fix find-references for import aliases (#21736)
  [ty] add tests for workspaces (#21741)
  [ty] Stop testing the (brittle) constraint set display implementation (#21743)
  [ty] Use generator over list comprehension to avoid cast (#21748)
  [ty] Add a diagnostic for prohibited `NamedTuple` attribute overrides (#21717)
  [ty] Fix subtyping with `type[T]` and unions (#21740)
  Use `npm ci --ignore-scripts` everywhere (#21742)
  [`flake8-simplify`] Fix truthiness assumption for non-iterable arguments in tuple/list/set calls (`SIM222`, `SIM223`) (#21479)
  [`flake8-use-pathlib`] Mark fixes unsafe for return type changes (`PTH104`, `PTH105`, `PTH109`, `PTH115`) (#21440)
  [ty] Fix auto-import code action to handle pre-existing import
  Enable PEP 740 attestations when publishing to PyPI (#21735)
  [ty] Fix find references for type defined in stub (#21732)
  Use OIDC instead of codspeed token (#21719)
  [ty] Exclude `typing_extensions` from completions unless it's really available
  [ty] Fix false positives for `class F(Generic[*Ts]): ...` (#21723)
  ...
2025-12-02 14:23:15 -05:00
Micha Reiser
515de2d062 Move Token, TokenKind and Tokens to ruff-python-ast (#21760) 2025-12-02 20:10:46 +01:00
Douglas Creager
508c0a0861 [ty] Don't confuse multiple occurrences of typing.Self when binding bound methods (#21754)
In the following example, there are two occurrences of `typing.Self`,
one for `Foo.foo` and one for `Bar.bar`:

```py
from typing import Self, reveal_type

class Foo[T]:
    def foo(self: Self) -> T:
        raise NotImplementedError

class Bar:
    def bar(self: Self, x: Foo[Self]):
        # SHOULD BE: bound method Foo[Self@bar].foo() -> Self@bar
        # revealed: bound method Foo[Self@bar].foo() -> Foo[Self@bar]
        reveal_type(x.foo)

def f[U: Bar](x: Foo[U]):
    # revealed: bound method Foo[U@f].foo() -> U@f
    reveal_type(x.foo)
```

When accessing a bound method, we replace any occurrences of `Self` with
the bound `self` type.

We were doing this correctly for the second reveal. We would first apply
the specialization, getting `(self: Self@foo) -> U@F` as the signature
of `x.foo`. We would then bind the `self` parameter, substituting
`Self@foo` with `Foo[U@F]` as part of that. The return type was already
specialized to `U@F`, so that substitution had no further affect on the
type that we revealed.

In the first reveal, we would follow the same process, but we confused
the two occurrences of `Self`. We would first apply the specialization,
getting `(self: Self@foo) -> Self@bar` as the method signature. We would
then try to bind the `self` parameter, substituting `Self@foo` with
`Foo[Self@bar]`. However, because we didn't distinguish the two separate
`Self`s, and applied the substitution to the return type as well as to
the `self` parameter.

The fix is to track which particular `Self` we're trying to substitute
when applying the type mapping.

Fixes https://github.com/astral-sh/ty/issues/1713
2025-12-02 13:15:09 -05:00
Alex Waygood
ac2552b11b [ty] Move all_members, and related types/routines, out of ide_support.rs (#21695) 2025-12-02 14:45:24 +00:00
Micha Reiser
644096ea8a [ty] Fix find-references for import aliases (#21736) 2025-12-02 14:37:50 +01:00
Aria Desires
015ab9e576 [ty] add tests for workspaces (#21741)
Here are a bunch of (variously failing and passing) mdtests that reflect
the kinds of issues people encounter when running ty over an entire
workspace without sufficient hand-holding (especially because in the IDE
it is unclear *how* to provide that hand-holding).
2025-12-02 06:43:41 -05:00
Douglas Creager
cf4196466c [ty] Stop testing the (brittle) constraint set display implementation (#21743)
The `Display` implementation for constraint sets is brittle, and
deserves a rethink. But later! It's perfectly fine for printf debugging;
we just shouldn't be writing mdtests that depend on any particular
rendering details. Most of these tests can be replaced with an
equivalence check that actually validates that the _behavior_ of two
constraint sets are identical.
2025-12-02 09:17:29 +01:00
Charlie Marsh
72304b01eb [ty] Add a diagnostic for prohibited NamedTuple attribute overrides (#21717)
## Summary

Closes https://github.com/astral-sh/ty/issues/1684.
2025-12-01 21:46:58 -05:00
Ibraheem Ahmed
ec854c7199 [ty] Fix subtyping with type[T] and unions (#21740)
## Summary

Resolves
https://github.com/astral-sh/ruff/pull/21685#issuecomment-3591695954.
2025-12-01 18:20:13 -05:00
Andrew Gallant
a561e6659d [ty] Exclude typing_extensions from completions unless it's really available
This works by adding a third module resolution mode that lets the caller
opt into _some_ shadowing of modules that is otherwise not allowed (for
`typing` and `typing_extensions`).

Fixes astral-sh/ty#1658
2025-12-01 11:24:16 -05:00
Alex Waygood
0e651b50b7 [ty] Fix false positives for class F(Generic[*Ts]): ... (#21723) 2025-12-01 13:24:07 +00:00
David Peter
116fd7c7af [ty] Remove GenericAlias-related todo type (#21728)
## Summary

If you manage to create an `typing.GenericAlias` instance without us
knowing how that was created, then we don't know what to do with this in
a type annotation. So it's better to be explicit and show an error
instead of failing silently with a `@Todo` type.

## Test Plan

* New Markdown tests
* Zero ecosystem impact
2025-12-01 13:02:38 +00:00
David Peter
5358ddae88 [ty] Exhaustiveness checking for generic classes (#21726)
## Summary

We had tests for this already, but they used generic classes that were
bivariant in their type parameter, and so this case wasn't captured.

closes https://github.com/astral-sh/ty/issues/1702

## Test Plan

Updated Markdown tests
2025-12-01 13:52:36 +01:00
Alex Waygood
3a11e714c6 [ty] Show the user where the type variable was defined in invalid-type-arguments diagnostics (#21727) 2025-12-01 12:25:49 +00:00
Alex Waygood
a2096ee2cb [ty] Emit invalid-named-tuple on namedtuple classes that have field names starting with underscores (#21697) 2025-12-01 11:36:02 +00:00
Carl Meyer
c2773b4c6f [ty] support type[tuple[...]] (#21652)
Fixes https://github.com/astral-sh/ty/issues/1649

## Summary

We missed this when adding support for `type[]` of a specialized
generic.

## Test Plan

Added mdtests.
2025-12-01 11:49:26 +01:00
David Peter
bc6517a807 [ty] Add missing projects to good.txt (#21721)
## Summary

These projects from `mypy_primer` were missing from both `good.txt` and
`bad.txt` for some reason. I thought about writing a script that would
verify that `good.txt` + `bad.txt` = `mypy_primer.projects`, but that's
not completely trivial since there are projects like `cpython` only
appear once in `good.txt`. Given that we can hopefully soon get rid of
both of these files (and always run on all projects), it's probably not
worth the effort. We are usually notified of all `mypy_primer` changes.

## Test Plan

CI on this PR
2025-12-01 11:18:41 +01:00
Shunsuke Shibayama
a6cbc138d2 [ty] remove the visitor parameter in the recursive_type_normalized_impl method (#21701) 2025-12-01 08:48:43 +01:00
Charlie Marsh
e7beb7e1f4 [ty] Forbid use of super() in NamedTuple subclasses (#21700)
## Summary

The exact behavior around what's allowed vs. disallowed was partly
detected through trial and error in the runtime.

I was a little confused by [this
comment](https://github.com/python/cpython/pull/129352) that says
"`NamedTuple` subclasses cannot be inherited from" because in practice
that doesn't appear to error at runtime.

Closes [#1683](https://github.com/astral-sh/ty/issues/1683).
2025-11-30 15:49:06 +00:00
Alex Waygood
b02e8212c9 [ty] Don't introduce invalid syntax when autofixing override-of-final-method (#21699) 2025-11-30 13:40:33 +00:00
Alex Waygood
69ace00210 [ty] Rename types::liskov to types::overrides (#21694) 2025-11-29 14:54:00 +00:00
Micha Reiser
d40590c8f9 [ty] Add code action to ignore diagnostic on the current line (#21595) 2025-11-29 15:41:54 +01:00
RasmusNygren
b2387f4eab [ty] fix typo in HasDefinition trait docstring (#21689)
## Summary
Fixes a typo in the docstring for the definition method in the
HasDefinition trait
2025-11-29 11:13:54 +00:00
Dhruv Manilawala
8795d9f0cb [ty] Split ParamSpec mdtests to separate legacy and PEP 695 tests (#21687)
## Summary

This is another small refactor for
https://github.com/astral-sh/ruff/pull/21445 that splits the single
`paramspec.md` into `generics/legacy/paramspec.md` and
`generics/pep695/paramspec.md`.

## Test Plan

Make sure that all mdtests pass.
2025-11-29 06:49:39 +00:00
David Peter
42f152108a [ty] Generic types aliases (implicit and PEP 613) (#21553)
## Summary

Add support for generic PEP 613 type aliases and generic implicit type
aliases:
```py
from typing import TypeVar

T = TypeVar("T")
ListOrSet = list[T] | set[T]

def _(xs: ListOrSet[int]):
    reveal_type(xs)  # list[int] | set[int]
```

closes https://github.com/astral-sh/ty/issues/1643
closes https://github.com/astral-sh/ty/issues/1629
closes https://github.com/astral-sh/ty/issues/1596
closes https://github.com/astral-sh/ty/issues/573
closes https://github.com/astral-sh/ty/issues/221

## Typing conformance

```diff
-aliases_explicit.py:52:5: error[type-assertion-failure] Type `list[int]` does not match asserted type `@Todo(specialized generic alias in type expression)`
-aliases_explicit.py:53:5: error[type-assertion-failure] Type `tuple[str, ...] | list[str]` does not match asserted type `@Todo(Generic specialization of types.UnionType)`
-aliases_explicit.py:54:5: error[type-assertion-failure] Type `tuple[int, int, int, str]` does not match asserted type `@Todo(specialized generic alias in type expression)`
-aliases_explicit.py:56:5: error[type-assertion-failure] Type `(int, str, /) -> str` does not match asserted type `@Todo(Generic specialization of typing.Callable)`
-aliases_explicit.py:59:5: error[type-assertion-failure] Type `int | str | None | list[list[int]]` does not match asserted type `int | str | None | list[@Todo(specialized generic alias in type expression)]`
```

New true negatives ✔️ 

```diff
+aliases_explicit.py:41:36: error[invalid-type-arguments] Too many type arguments: expected 1, got 2
-aliases_explicit.py:57:5: error[type-assertion-failure] Type `(int, str, str, /) -> None` does not match asserted type `@Todo(Generic specialization of typing.Callable)`
+aliases_explicit.py:57:5: error[type-assertion-failure] Type `(int, str, str, /) -> None` does not match asserted type `(...) -> Unknown`
```

These require `ParamSpec`

```diff
+aliases_explicit.py:67:24: error[invalid-type-arguments] Too many type arguments: expected 0, got 1
+aliases_explicit.py:68:24: error[invalid-type-arguments] Too many type arguments: expected 0, got 1
+aliases_explicit.py:69:29: error[invalid-type-arguments] Too many type arguments: expected 1, got 2
+aliases_explicit.py:70:29: error[invalid-type-arguments] Too many type arguments: expected 1, got 2
+aliases_explicit.py:71:29: error[invalid-type-arguments] Too many type arguments: expected 1, got 2
+aliases_explicit.py:102:20: error[invalid-type-arguments] Too many type arguments: expected 0, got 1
```

New true positives ✔️ 

```diff
-aliases_implicit.py:63:5: error[type-assertion-failure] Type `list[int]` does not match asserted type `@Todo(specialized generic alias in type expression)`
-aliases_implicit.py:64:5: error[type-assertion-failure] Type `tuple[str, ...] | list[str]` does not match asserted type `@Todo(Generic specialization of types.UnionType)`
-aliases_implicit.py:65:5: error[type-assertion-failure] Type `tuple[int, int, int, str]` does not match asserted type `@Todo(specialized generic alias in type expression)`
-aliases_implicit.py:67:5: error[type-assertion-failure] Type `(int, str, /) -> str` does not match asserted type `@Todo(Generic specialization of typing.Callable)`
-aliases_implicit.py:70:5: error[type-assertion-failure] Type `int | str | None | list[list[int]]` does not match asserted type `int | str | None | list[@Todo(specialized generic alias in type expression)]`
-aliases_implicit.py:71:5: error[type-assertion-failure] Type `list[bool]` does not match asserted type `@Todo(specialized generic alias in type expression)`
```

New true negatives ✔️ 

```diff
+aliases_implicit.py:54:36: error[invalid-type-arguments] Too many type arguments: expected 1, got 2
-aliases_implicit.py:68:5: error[type-assertion-failure] Type `(int, str, str, /) -> None` does not match asserted type `@Todo(Generic specialization of typing.Callable)`
+aliases_implicit.py:68:5: error[type-assertion-failure] Type `(int, str, str, /) -> None` does not match asserted type `(...) -> Unknown`
```

These require `ParamSpec`

```diff
+aliases_implicit.py:76:24: error[invalid-type-arguments] Too many type arguments: expected 0, got 1
+aliases_implicit.py:77:24: error[invalid-type-arguments] Too many type arguments: expected 0, got 1
+aliases_implicit.py:78:29: error[invalid-type-arguments] Too many type arguments: expected 1, got 2
+aliases_implicit.py:79:29: error[invalid-type-arguments] Too many type arguments: expected 1, got 2
+aliases_implicit.py:80:29: error[invalid-type-arguments] Too many type arguments: expected 1, got 2
+aliases_implicit.py:81:25: error[invalid-type-arguments] Type `str` is not assignable to upper bound `int | float` of type variable `TFloat@GoodTypeAlias12`
+aliases_implicit.py:135:20: error[invalid-type-arguments] Too many type arguments: expected 0, got 1
```

New true positives ✔️ 

```diff
+callables_annotation.py:172:19: error[invalid-type-arguments] Too many type arguments: expected 0, got 1
+callables_annotation.py:175:19: error[invalid-type-arguments] Too many type arguments: expected 0, got 1
+callables_annotation.py:188:25: error[invalid-type-arguments] Too many type arguments: expected 0, got 1
+callables_annotation.py:189:25: error[invalid-type-arguments] Too many type arguments: expected 0, got 1
```

These require `ParamSpec` and `Concatenate`.

```diff
-generics_defaults_specialization.py:26:5: error[type-assertion-failure] Type `SomethingWithNoDefaults[int, str]` does not match asserted type `SomethingWithNoDefaults[int, typing.TypeVar]`
+generics_defaults_specialization.py:26:5: error[type-assertion-failure] Type `SomethingWithNoDefaults[int, str]` does not match asserted type `SomethingWithNoDefaults[int, DefaultStrT]`
```

Favorable diagnostic change ✔️ 

```diff
-generics_defaults_specialization.py:27:5: error[type-assertion-failure] Type `SomethingWithNoDefaults[int, bool]` does not match asserted type `@Todo(specialized generic alias in type expression)`
```

New true negative ✔️ 

```diff
-generics_defaults_specialization.py:30:1: error[non-subscriptable] Cannot subscript object of type `<class 'SomethingWithNoDefaults[int, typing.TypeVar]'>` with no `__class_getitem__` method
+generics_defaults_specialization.py:30:15: error[invalid-type-arguments] Too many type arguments: expected between 0 and 1, got 2
```

Correct new diagnostic ✔️ 


```diff
-generics_variance.py:175:25: error[non-subscriptable] Cannot subscript object of type `<class 'Contra[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:175:35: error[non-subscriptable] Cannot subscript object of type `<class 'Co[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:179:29: error[non-subscriptable] Cannot subscript object of type `<class 'Contra[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:179:39: error[non-subscriptable] Cannot subscript object of type `<class 'Contra[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:183:21: error[non-subscriptable] Cannot subscript object of type `<class 'Co[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:183:27: error[non-subscriptable] Cannot subscript object of type `<class 'Co[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:187:25: error[non-subscriptable] Cannot subscript object of type `<class 'Co[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:187:31: error[non-subscriptable] Cannot subscript object of type `<class 'Contra[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:191:33: error[non-subscriptable] Cannot subscript object of type `<class 'Contra[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:191:43: error[non-subscriptable] Cannot subscript object of type `<class 'Co[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:191:49: error[non-subscriptable] Cannot subscript object of type `<class 'Contra[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:196:5: error[non-subscriptable] Cannot subscript object of type `<class 'Contra[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:196:15: error[non-subscriptable] Cannot subscript object of type `<class 'Contra[typing.TypeVar]'>` with no `__class_getitem__` method
-generics_variance.py:196:25: error[non-subscriptable] Cannot subscript object of type `<class 'Contra[typing.TypeVar]'>` with no `__class_getitem__` method
```

One of these should apparently be an error, but not of this kind, so
this is good ✔️

```diff
-specialtypes_type.py:152:16: error[invalid-type-form] `typing.TypeVar` is not a generic class
-specialtypes_type.py:156:16: error[invalid-type-form] `typing.TypeVar` is not a generic class
```

Good, those were false positives. ✔️ 

I skipped the analysis for everything involving `TypeVarTuple`.

## Ecosystem impact

**[Full report with detailed
diff](https://david-generic-implicit-alias.ecosystem-663.pages.dev/diff)**

Previous iterations of this PR showed all kinds of problems. In it's
current state, I do not see any large systematic problems, but it is
hard to tell with 5k diagnostic changes.

## Performance

* There is a huge 4x regression in `colour-science/colour`, related to
[this large
file](https://github.com/colour-science/colour/blob/develop/colour/io/luts/tests/test_lut.py)
with [many assignments of hard-coded arrays (lists of lists) to
`np.NDArray`
types](83e754c8b6/colour/io/luts/tests/test_lut.py (L701-L781))
that we now understand. We now take ~2 seconds to check this file, so
definitely not great, but maybe acceptable for now.

## Test Plan

Updated and new Markdown tests
2025-11-28 20:38:24 +01:00
Alex Waygood
594b7b04d3 [ty] Preserve quoting style when autofixing TypedDict keys (#21682) 2025-11-28 18:40:34 +00:00
Matthew Mckee
b5b4917d7f [ty] Fix override of final method summary (#21681) 2025-11-28 16:18:22 +00:00
David Peter
0084e94f78 [ty] Fix subtyping of type[Any] / type[T] and protocols (#21678)
## Summary

This is a bugfix for subtyping of `type[Any]` / `type[T]` and protocols.

## Test Plan

Regression test that will only be really meaningful once
https://github.com/astral-sh/ruff/pull/21553 lands.
2025-11-28 16:56:22 +01:00
Alex Waygood
8bcfc198b8 [ty] Implement typing.final for methods (#21646)
Co-authored-by: Micha Reiser <micha@reiser.io>
2025-11-28 15:18:02 +00:00
Aria Desires
c534bfaf01 [ty] Implement patterns and typevars in the LSP (#21671)
## Summary

**This is the final goto-targets with missing
goto-definition/declaration implementations!
You can now theoretically click on all the user-defined names in all the
syntax. 🎉**

This adds:

* goto definition/declaration on patterns/typevars
* find-references/rename on patterns/typevars
* fixes syntax highlighting of `*rest` patterns

This notably *does not* add:

* goto-type for patterns/typevars 
* hover for patterns/typevars (because that's just goto-type for names)

Also I realized we were at the precipice of one of the great GotoTarget
sins being resolved, and so I made import aliases also resolve to a
ResolvedDefinition. This removes a ton of cruft and prevents further
backsliding.

Note however that import aliases are, in general, completely jacked up
when it comes to find-references/renames (both before and after this
PR). Previously you could try to rename an import alias and it just
wouldn't do anything. With this change we instead refuse to even let you
try to rename it.

Sorting out why import aliases are jacked up is an ongoing thing I hope
to handle in a followup.

## Test Plan

You'll surely not regret checking in 86 snapshot tests
2025-11-28 13:41:21 +00:00
Dhruv Manilawala
98681b9356 [ty] Add db parameter to Parameters::new method (#21674)
## Summary

This PR adds a new `db` parameter to `Parameters::new` for
https://github.com/astral-sh/ruff/pull/21445. This change creates a
large diff so thought to split it out as it's just a mechanical change.

The `Parameters::new` method not only creates the `Parameters` but also
analyses the parameters to check what kind it is. For `ParamSpec`
support, it's going to require the `db` to check whether the annotated
type is `ParamSpec` or not. For the current set of parameters that isn't
required because it's only checking whether it's dynamic or not which
doesn't require `db`.
2025-11-28 12:29:58 +00:00
Ibraheem Ahmed
3ed537e9f1 [ty] Support type[T] with type variables (#21650)
## Summary

Adds support for `type[T]`, where `T` is a type variable.

- Resolves https://github.com/astral-sh/ty/issues/501
- Resolves https://github.com/astral-sh/ty/issues/783
- Resolves https://github.com/astral-sh/ty/issues/662
2025-11-28 09:20:24 +01:00
Alex Waygood
53efc82989 [ty] Include all members on type in autocompletion suggestions for type[] types (#21670) 2025-11-27 19:29:25 +00:00
Alex Waygood
aef2fad0c5 [ty] Add IDE autofixes for two "Did you mean...?" suggestions (#21667) 2025-11-27 18:20:02 +00:00
Aria Desires
e5818d89fd [ty] Add "import ..." code-action for unresolved references (#21629)
## Summary

Originally I planned to feed this in as a `fix` but I realized that we
probably don't want to be trying to resolve import suggestions while
we're doing type inference. Thus I implemented this as a fallback when
there's no fixes on a diagnostic, which can use the full lsp machinery.

Fixes https://github.com/astral-sh/ty/issues/1552

## Test Plan

Works in the IDE, added some e2e tests.
2025-11-27 10:06:38 -05:00
Alex Waygood
a7d48ffd40 [ty] Add subdiagnostic hint if a variable with type Never is used in a type expression (#21660) 2025-11-27 12:48:18 +00:00
Carl Meyer
77f8fa6906 [ty] more precise inference for a failed specialization (#21651)
## Summary

Previously if an explicit specialization failed (e.g. wrong number of
type arguments or violates an upper bound) we just inferred `Unknown`
for the entire type. This actually caused us to panic on an a case of a
recursive upper bound with invalid specialization; the upper bound would
oscillate indefinitely in fixpoint iteration between `Unknown` and the
given specialization. This could be fixed with a cycle recovery
function, but in this case there's a simpler fix: if we infer
`C[Unknown]` instead of `Unknown` for an invalid attempt to specialize
`C`, that allows fixpoint iteration to quickly converge, as well as
giving a more precise type inference.

Other type checkers actually just go with the attempted specialization
even if it's invalid. So if `C` has a type parameter with upper bound
`int`, and you say `C[str]`, they'll emit a diagnostic but just go with
`C[str]`. Even weirder, if `C` has a single type parameter and you say
`C[str, bytes]`, they'll just go with `C[str]` as the type. I'm not
convinced by this approach; it seems odd to have specializations
floating around that explicitly violate the declared upper bound, or in
the latter case aren't even the specialization the annotation requested.
I prefer `C[Unknown]` for this case.

Fixing this revealed an issue with `collections.namedtuple`, which
returns `type[tuple[Any, ...]]`. Due to
https://github.com/astral-sh/ty/issues/1649 we consider that to be an
invalid specialization. So previously we returned `Unknown`; after this
PR it would be `type[tuple[Unknown]]`, leading to more false positives
from our lack of functional namedtuple support. To avoid that I added an
explicit Todo type for functional namedtuples for now.

## Test Plan

Added and updated mdtests.

The conformance suite changes have to do with `ParamSpec`, so no
meaningful signal there.

The ecosystem changes appear to be the expected effects of having more
precise type information (including occurrences of known issues such as
https://github.com/astral-sh/ty/issues/1495 ). Most effects are just
changes to types in diagnostics.
2025-11-27 13:44:28 +01:00
Alex Waygood
792ec3e96e Improve docs on how to stop Ruff and ty disagreeing with each other (#21644)
## Summary

Lots of Ruff rules encourage you to make changes that might then cause
ty to start complaining about Liskov violations. Most of these Ruff
rules already refrain from complaining about a method if they see that
the method is decorated with `@override`, but this usually isn't
documented. This PR updates the docs of many Ruff rules to note that
they refrain from complaining about `@override`-decorated methods, and
also adds a similar note to the ty `invalid-method-override`
documentation.

Helps with
https://github.com/astral-sh/ty/issues/1644#issuecomment-3581663859

## Test Plan

- `uvx prek run -a` locally
- CI on this PR
2025-11-27 08:18:21 +00:00
Dhruv Manilawala
c7107a5a90 [ty] Use zip to perform explicit specialization (#21635)
## Summary

This PR updates the explicit specialization logic to avoid using the
call machinery.

Previously, the logic would use the call machinery by converting the
list of type variables into a `Binding` with a single `Signature` where
all the type variables are positional-only parameters with bounds and
constraints as the annotated type and the default type as the default
parameter value. This has the advantage that it doesn't need to
implement any specific logic but the disadvantages are subpar diagnostic
messages as it would use the ones specific to a function call. But, an
important disadvantage is that the kind of type variable is lost in this
translation which becomes important in #21445 where a `ParamSpec` can
specialize into a list of types which is provided using list literal.
For example,

```py
class Foo[T, **P]: ...

Foo[int, [int, str]]
```

This PR converts the logic to use a simple loop using `zip_longest` as
all type variables and their corresponding type argument maps on a 1-1
basis. They cannot be specified using keyword argument either e.g.,
`dict[_VT=str, _KT=int]` is invalid.

This PR also makes an initial attempt to improve the diagnostic message
to specifically target the specialization part by using words like "type
argument" instead of just "argument" and including information like the
type variable, bounds, and constraints. Further improvements can be made
by highlighting the type variable definition or the bounds / constraints
as a sub-diagnostic but I'm going to leave that as a follow-up.

## Test Plan

Update messages in existing test cases.
2025-11-27 03:52:22 +00:00
Carl Meyer
e0f3a064b9 [ty] don't iterate over a hashset (#21649)
## Summary

This caused "deterministic but chaotic" ordering of some intersection
types in diagnostics. When calling a union, we infer the argument type
once per matching parameter type, intersecting the inferred types for
the argument expression, and we did that in an unpredictable order.

We do need a hashset here for de-duplication. Sometimes we call large
unions where the type for a given parameter is the same across the
union, we should infer the argument once per parameter type, not once
per union element. So use an `FxIndexSet` instead of an `FxHashSet`.

## Test Plan

With this change, switching between `main` and
https://github.com/astral-sh/ruff/pull/21646 no longer changes the
ordering of the intersection type in the test in
cca3a8045d
2025-11-26 16:39:49 -08:00
Douglas Creager
2c6267436f clean up the diff 2025-11-26 18:35:15 -05:00
Douglas Creager
fedc75463b this gets recursively expanded now 2025-11-26 18:35:15 -05:00
Douglas Creager
9950c126fe these need to be positional only to be assignable 2025-11-26 18:35:15 -05:00
Douglas Creager
b7fb6797b4 it works! 2025-11-26 18:35:15 -05:00
Douglas Creager
fc2f17508b use constraint set assignable 2025-11-26 18:35:15 -05:00
Douglas Creager
20ecb561bb add ConstraintSetAssignability relation 2025-11-26 18:35:15 -05:00
Douglas Creager
3b509e9015 it's a start 2025-11-26 18:35:15 -05:00
Douglas Creager
998b20f078 add for_each_path 2025-11-26 18:35:15 -05:00
Douglas Creager
544dafa66e add more sequents 2025-11-26 18:35:15 -05:00