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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Part of #18972
This PR makes [snake-case-type-alias
(PYI042)](https://docs.astral.sh/ruff/rules/snake-case-type-alias/#snake-case-type-alias-pyi042)'s
example error out-of-the-box
[Old example](https://play.ruff.rs/8fafec81-2228-4ffe-81e8-1989b724cb47)
```py
type_alias_name: TypeAlias = int
```
[New example](https://play.ruff.rs/b396746c-e6d2-423c-bc13-01a533bb0747)
```py
from typing import TypeAlias
type_alias_name: TypeAlias = int
```
Imports were also added to the "use instead" section.
## Test Plan
<!-- How was it tested? -->
N/A, no functionality/tests affected
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
This fixes the docs for [expressions-in-star-assignment
(F621)](https://docs.astral.sh/ruff/rules/expressions-in-star-assignment/#expressions-in-star-assignment-f621)
having a backslash `\` before the left shifts `<<`. I'm not sure why
this happened in the first place, as the docstring looks fine, but
putting the `<<` inside a code block fixes it. I was not able to track
down the source of the issue either. The only other rule with a `<<` is
[missing-whitespace-around-bitwise-or-shift-operator
(E227)](https://docs.astral.sh/ruff/rules/missing-whitespace-around-bitwise-or-shift-operator/#missing-whitespace-around-bitwise-or-shift-operator-e227),
which already has it in a code block.
Old docs page:
> In Python 3, no more than 1 \\<< 8 assignments are allowed before a
starred expression, and no more than 1 \\<< 24 expressions are allowed
after a starred expression.
New docs page:
> In Python 3, no more than `1 << 8` assignments are allowed before a
starred expression, and no more than `1 << 24` expressions are allowed
after a starred expression.
## Test Plan
<!-- How was it tested? -->
N/A, no tests/functionality affected.
## Summary
Allow declared-only class-level attributes to be accessed on the class:
```py
class C:
attr: int
C.attr # this is now allowed
```
closes https://github.com/astral-sh/ty/issues/384
closes https://github.com/astral-sh/ty/issues/553
## Ecosystem analysis
* We see many removed `unresolved-attribute` false-positives for code
that makes use of sqlalchemy, as expected (see changes for `prefect`)
* We see many removed `call-non-callable` false-positives for uses of
`pytest.skip` and similar, as expected
* Most new diagnostics seem to be related to cases like the following,
where we previously inferred `int` for `Derived().x`, but now we infer
`int | None`. I think this should be a
conflicting-declarations/bad-override error anyway? The new behavior may
even be preferred here?
```py
class Base:
x: int | None
class Derived(Base):
def __init__(self):
self.x: int = 1
```
## Summary
The motivation of `ScopedExpressionId` was that we have an expression
identifier that's local to a scope and, therefore, unlikely to change if
a user makes changes in another scope. A local identifier like this has
the advantage that query results may remain unchanged even if other
parts of the file change, which in turn allows Salsa to short-circuit
dependent queries.
However, I noticed that we aren't using `ScopedExpressionId` in a place
where it's important that the identifier is local. It's main use is
inside `infer` which we always run for the entire file. The one
exception to this is `Unpack` but unpack runs as part of `infer`.
Edit: The above isn't entirely correct. We used ScopedExpressionId in
TypeInference which is a query result. Now using ExpressionNodeKey does
mean that a change to the AST invalidates most if not all TypeInference
results of a single file. Salsa then has to run all dependent queries to
see if they're affected by this change even if the change was local to
another scope.
If this locality proves to be important I suggest that we create two
queries on top of TypeInference: one that returns the expression map
which is mainly used in the linter and type inference and a second that
returns all remaining fields. This should give us a similar optimization
at a much lower cost
I also considered remove `ScopedUseId` but I believe that one is still
useful because using `ExpressionNodeKey` for it instead would mean that
all `UseDefMap` change when a single AST node changes. Whether this is
important is something difficult to assess. I'm simply not familiar
enough with the `UseDefMap`. If the locality doesn't matter for the
`UseDefMap`, then a similar change could be made and `bindings_by_use`
could be changed to an `FxHashMap<UseId, Bindings>` where `UseId` is a
thin wrapper around `NodeKey`.
Closes https://github.com/astral-sh/ty/issues/721
## Summary
This PR updates Salsa to pull in Ibraheem's multithreading improvements (https://github.com/salsa-rs/salsa/pull/921).
## Performance
A small regression for single-threaded benchmarks is expected because
papaya is slightly slower than a `Mutex<FxHashMap>` in the uncontested
case (~10%). However, this shouldn't matter as much in practice because:
1. Salsa has a fast-path when only using 1 DB instance which is the
common case in production. This fast-path is not impacted by the changes
but we measure the slow paths in our benchmarks (because we use multiple
db instances)
2. Fixing the 10x slowdown for the congested case (multi threading)
outweights the downsides of a 10% perf regression for single threaded
use cases, especially considering that ty is heavily multi threaded.
## Test Plan
`cargo test`
## Summary
Extracts the vendored typeshed stubs lazily and caches them on the local
filesystem to support go-to in the LSP.
Resolves https://github.com/astral-sh/ty/issues/77.
## Summary
This PR makes the necessary changes to the server that it can request
configurations from the client using the `configuration` request.
This PR doesn't make use of the request yet. It only sets up the
foundation (mainly the coordination between client and server)
so that future PRs could pull specific settings.
I plan to use this for pulling the Python environment from the Python
extension.
Deno does something very similar to this.
## Test Plan
Tested that diagnostics are still shown.
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Part of #18972
This PR makes [duplicate-literal-member
(PYI062)](https://docs.astral.sh/ruff/rules/duplicate-literal-member/#duplicate-literal-member-pyi062)'s
example error out-of-the-box
[Old example](https://play.ruff.rs/6b00b41c-c1c5-4421-873d-fc2a143e7337)
```py
foo: Literal["a", "b", "a"]
```
[New example](https://play.ruff.rs/1aea839b-9ae8-4848-bb83-2637e1a68ce4)
```py
from typing import Literal
foo: Literal["a", "b", "a"]
```
Imports were also added to the "use instead" section.
## Test Plan
<!-- How was it tested? -->
N/A, no functionality/tests affected
Follow-up to https://github.com/astral-sh/ruff/pull/19083, also log the
target names like `ty_python_semantic::module_resolver::resolver` in
`2025-07-02 10:12:20.188697000 DEBUG
ty_python_semantic::module_resolver::resolver: Adding first-party search
path '/Users/dhruv/playground/ty_server'` at trace level.
## Summary
I hoped this might fix the latest stack overflows on
https://github.com/astral-sh/ruff/pull/18659... it doesn't look like it
does, but these changes seem like they're probably correct anyway...?
## Test Plan
<!-- How was it tested? -->
https://github.com/ankitects/anki/pull/4119
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## Summary
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Add Anki to Who's Using Ruff (README)
---------
Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
This PR fixes#19047 / the [isinstance-type-none
(FURB168)](https://docs.astral.sh/ruff/rules/isinstance-type-none/#isinstance-type-none-furb168)
tuple false positive by adding a check if the tuple is empty to the
code. I also noticed there was another false positive with the other
tuple check in the same function, so I fixed it the same way.
`Union[()]` is invalid at runtime with `TypeError: Cannot take a Union
of no types.`, but it is accepted by `basedpyright`
[playground](https://basedpyright.com/?pythonVersion=3.8&typeCheckingMode=all&code=GYJw9gtgBALgngBwJYDsDmUkQWEMoCqKSYKAsAFAgCmAbtQIYA2A%2BvAtQBREkoDanAJQBdQUA)
and is equivalent to `Never`, so I fixed it anyways. I'm getting on a
side tangent here, but it looks like MyPy doesn't accept it, and ty
[playground](https://play.ty.dev/c2c468b6-38e4-4dd9-a9fa-0276e843e395)
gives `@Todo`.
## Test Plan
<!-- How was it tested? -->
Added two test cases for the two false positives.
[playground](https://play.ruff.rs/a53afc21-9a1d-4b9b-9346-abfbeabeb449)
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Part of #18972
This PR makes [datetime-min-max
(DTZ901)](https://docs.astral.sh/ruff/rules/datetime-min-max/#datetime-min-max-dtz901)'s
example error out-of-the-box
[Old example](https://play.ruff.rs/c1202727-1a18-4d3f-92a4-334ede07ed3e)
```py
datetime.max
```
[New example](https://play.ruff.rs/af2c76aa-9beb-46bc-8e27-faf53ecdbe8c)
```py
import datetime
datetime.datetime.max
```
I also added imports to the problem demonstration and use instead.
## Test Plan
<!-- How was it tested? -->
N/A, no functionality/tests affected
## Summary
Remove a hack in control flow modeling that was treating `return`
statements at the end of function bodies in a special way (basically
considering the state *just before* the `return` statement as the
end-of-scope state). This is not needed anymore now that #18750 has been
merged.
In order to make this work, we now use *all reachable bindings* for
purposes of finding implicit instance attribute assignments as well as
for deferred lookups of symbols. Both would otherwise be affected by
this change:
```py
def C:
def f(self):
self.x = 1 # a reachable binding that is not visible at the end of the scope
return
```
```py
def f():
class X: ... # a reachable binding that is not visible at the end of the scope
x: "X" = X() # deferred use of `X`
return
```
Implicit instance attributes also required another change. We previously
kept track of possibly-unbound instance attributes in some cases, but we
now give up on that completely and always consider *implicit* instance
attributes to be bound if we see a reachable binding in a reachable
method. The previous behavior was somewhat inconsistent anyway because
we also do not consider attributes possibly-unbound in other scenarios:
we do not (and can not) keep track of whether or not methods are called
that define these attributes.
closes https://github.com/astral-sh/ty/issues/711
## Ecosystem analysis
I think this looks very positive!
* We see an unsurprising drop in `possibly-unbound-attribute`
diagnostics (599), mostly for classes that define attributes in `try …
except` blocks, `for` loops, or `if … else: raise …` constructs. There
might obviously also be true positives that got removed, but the vast
majority should be false positives.
* There is also a drop in `possibly-unresolved-reference` /
`unresolved-reference` diagnostics (279+13) from the change to deferred
lookups.
* Some `invalid-type-form` false positives got resolved (13), because we
can now properly look up the names in the annotations.
* There are some new *true* positives in `attrs`, since we understand
the `Attribute` annotation that was previously inferred as `Unknown`
because of a re-assignment after the class definition.
## Test Plan
The existing attributes.md test suite has sufficient coverage here.
## Summary
Temporarily modify `UseDefMapBuilder::reachability` for star imports in
order for new definitions to pick up the right reachability. This was
already working for `UseDefMapBuilder::place_states`, but not for
`UseDefMapBuilder::reachable_definitions`.
closes https://github.com/astral-sh/ty/issues/728
## Test Plan
Regression test
## Summary
Evaluate `TYPE_CHECKING` to `ALWAYS_TRUE` and `not TYPE_CHECKING` to
`ALWAYS_FALSE` during semantic index building. This is a follow-up to
https://github.com/astral-sh/ruff/pull/18998 and is in principle just a
performance optimization. We see some (favorable) ecosystem changes
because we can eliminate definitely-unreachable branches early now and
retain narrowing constraints without solving
https://github.com/astral-sh/ty/issues/690 first.
This PR contains the following updates:
| Package | Type | Update | Change |
|---|---|---|---|
| [get-size2](https://redirect.github.com/bircni/get-size2) |
workspace.dependencies | patch | `0.5.0` -> `0.5.1` |
---
> [!WARNING]
> Some dependencies could not be looked up. Check the Dependency
Dashboard for more information.
---
### Release Notes
<details>
<summary>bircni/get-size2 (get-size2)</summary>
###
[`v0.5.1`](https://redirect.github.com/bircni/get-size2/blob/HEAD/CHANGELOG.md#051---2025-06-25)
[Compare
Source](https://redirect.github.com/bircni/get-size2/compare/0.5.0...0.5.1)
##### Bug Fixes
- correctly determine size for enums
([#​24](https://redirect.github.com/bircni/get-size2/issues/24)) -
([3c5bd18](3c5bd18cac))
- Nicolas
##### Miscellaneous Chores
- add top-level `heap_size` function
([#​25](https://redirect.github.com/bircni/get-size2/issues/25)) -
([f3b5e6e](f3b5e6e38c))
- Ibraheem Ahmed
##### Build
- update to newer cargo-verset to set dependency version automatically -
([b1154e4](b1154e4572))
- Nicolas
</details>
---
### Configuration
📅 **Schedule**: Branch creation - "before 4am on Monday" (UTC),
Automerge - At any time (no schedule defined).
🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.
♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the
rebase/retry checkbox.
🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.
---
- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box
---
This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
log](https://developer.mend.io/github/astral-sh/ruff).
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Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Gates all uses of `get-size2` behind the feature `get-size` in the crate
`ruff_python_ast`. Also requires that `ruff_text_size` is pulled in with
the feature `get-size` enabled if we enable the same-named feature for
`ruff_python_ast`.
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## Summary
Make `UP045` ignore `Optional[NamedTuple]` as `NamedTuple` is a function
(not a proper type). Rewriting it to `NamedTuple | None` breaks at
runtime. While type checkers currently accept `NamedTuple` as a type,
they arguably shouldn't. Therefore, we outright ignore it and don't
touch or lint on it.
For a more detailed discussion, see the linked issue.
## Test Plan
Added examples to the existing tests.
## Related Issues
Fixes: https://github.com/astral-sh/ruff/issues/18619
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Part of #18972
This PR makes [call-date-today
(DTZ011)](https://docs.astral.sh/ruff/rules/call-date-today/#call-date-today-dtz011)'s
example error out-of-the-box
[Old example](https://play.ruff.rs/b42d6aef-7777-4b3b-9f96-19132000b765)
```py
import datetime
datetime.datetime.today()
```
[New example](https://play.ruff.rs/8577c3c1-cfa8-425b-b1e1-4c53b2a48375)
```py
import datetime
datetime.date.today()
```
## Test Plan
<!-- How was it tested? -->
N/A, no functionality/tests affected
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Part of #18972
This PR makes [no-explicit-stacklevel
(B028)](https://docs.astral.sh/ruff/rules/no-explicit-stacklevel/#no-explicit-stacklevel-b028)'s
example error out-of-the-box
[Old example](https://play.ruff.rs/1ee80aec-2d6e-4a3f-8e98-da82b6a9f544)
```py
warnings.warn("This is a warning")
```
[New example](https://play.ruff.rs/343593aa-38a0-4d76-a32b-5abd0a4306cc)
```py
import warnings
warnings.warn("This is a warning")
```
Imports were also added to the "use instead" section
## Test Plan
<!-- How was it tested? -->
N/A, no functionality/tests affected
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Part of #18972
This PR makes [batched-without-explicit-strict
(B911)](https://docs.astral.sh/ruff/rules/batched-without-explicit-strict/#batched-without-explicit-strict-b911)'s
example error out-of-the-box
[Old example](https://play.ruff.rs/a897d96b-0749-4291-8a62-dfd4caf290a0)
```py
itertools.batched(iterable, n)
```
[New example](https://play.ruff.rs/1c1e0ab7-014c-4dc2-abed-c2cb6cd01f70)
```py
import itertools
itertools.batched(iterable, n)
```
Imports were also added to the "use instead" sections
## Test Plan
<!-- How was it tested? -->
N/A, no functionality/tests affected
## Summary
This just replaces one temporary solution to recursive protocols (the
`SelfReference` mechanism) with another one (track seen types when
recursively descending in `normalize` and replace recursive references
with `Any`). But this temporary solution can handle mutually-recursive
types, not just self-referential ones, and it's sufficient for the
primer ecosystem and some other projects we are testing on to no longer
stack overflow.
The follow-up here will be to properly handle these self-references
instead of replacing them with `Any`.
We will also eventually need cycle detection on more recursive-descent
type transformations and tests.
## Test Plan
Existing tests (including recursive-protocol tests) and primer.
Added mdtest for mutually-recursive protocols that stack-overflowed
before this PR.
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## Summary
This PR fixes rule C420's fix. The fix replaces `{...}` with
`dict....(...)`. Therefore, if there is any identifier or such right
before the fix, the fix will fuse that previous token with `dict...`.
The example in the issue is
```python
0 or{x: None for x in "x"}
# gets "fixed" to
0 ordict.fromkeys(iterable)
```
## Related Issues
Fixes: https://github.com/astral-sh/ruff/issues/18599
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## Summary
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Fixes#18908
