## 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>
---
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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
<!-- What's the purpose of the change? What does it do, and why? -->
Fixes#18908
## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
As discussed on Slack, there was an issue with the walltime metrics with
`divan`. The issue was fixed with the latest version of `cargo-codspeed`
and `codpseed-divan-compat`:
https://github.com/CodSpeedHQ/codspeed-rust/releases/tag/v3.0.0.
This PR updates all crates related to CodSpeed. A performance increase
of the following benchmarks is expected, as now the correct metric will
be used.
```
crates/ruff_benchmark/benches/ty_walltime.rs::multithreaded[pydantic]
crates/ruff_benchmark/benches/ty_walltime.rs::small[altair]
crates/ruff_benchmark/benches/ty_walltime.rs::small[freqtrade]
crates/ruff_benchmark/benches/ty_walltime.rs::small[pydantic]
crates/ruff_benchmark/benches/ty_walltime.rs::small[tanjun]
```
Once this is merged, we will update the historic data of the affected
benchmark on the CodSpeed UI, so that no false positives will appear.
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Part of #18972
This PR makes [airflow3-moved-to-provider
(AIR302)](https://docs.astral.sh/ruff/rules/airflow3-moved-to-provider/#airflow3-moved-to-provider-air302)'s
example error out-of-the-box
[Old example](https://play.ruff.rs/1026c008-57bc-4330-93b9-141444f2a611)
```py
from airflow.auth.managers.fab.fab_auth_manage import FabAuthManager
```
[New example](https://play.ruff.rs/b690e809-a81d-4265-9fde-1494caa0b7fd)
```py
from airflow.auth.managers.fab.fab_auth_manager import FabAuthManager
fab_auth_manager_app = FabAuthManager().get_fastapi_app()
```
## Test Plan
<!-- How was it tested? -->
N/A, no functionality/tests affected
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## Summary
Mark `UP008`'s fix safe if it won't delete comments.
## Relevant Issues
Fixes: https://github.com/astral-sh/ruff/issues/18533
---------
Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
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## Summary
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Part of #18972
This PR makes [flask-debug-true
(S201)](https://docs.astral.sh/ruff/rules/flask-debug-true/#flask-debug-true-s201)'s
example error out-of-the-box
[Old example](https://play.ruff.rs/d5e1a013-1107-4223-9094-0e8393ad3c64)
```py
import flask
app = Flask()
app.run(debug=True)
```
[New example](https://play.ruff.rs/c4aebd2c-0448-4471-8bad-3e38ace68367)
```py
from flask import Flask
app = Flask()
app.run(debug=True)
```
Imports were also added to the `Use instead:` section to make it valid
code out-of-the-box.
## Test Plan
<!-- How was it tested? -->
N/A, no functionality/tests affected
## Summary
Simplifies literal `True` and `False` conditions to `ALWAYS_TRUE` /
`ALWAYS_FALSE` during semantic index building. This allows us to eagerly
evaluate more constraints, which should help with performance (looks
like there is a tiny 1% improvement in instrumented benchmarks), but
also allows us to eliminate definitely-unreachable branches in
control-flow merging. This can lead to better type inference in some
cases because it allows us to retain narrowing constraints without
solving https://github.com/astral-sh/ty/issues/690 first:
```py
def _(c: int | None):
if c is None:
assert False
reveal_type(c) # int, previously: int | None
```
closes https://github.com/astral-sh/ty/issues/713
## Test Plan
* Regression test for https://github.com/astral-sh/ty/issues/713
* Made sure that all ecosystem diffs trace back to removed false
positives
## Summary
This PR adds diagnostic for invalid binary operators in type
expressions. It should close https://github.com/astral-sh/ty/issues/706
if merged.
Please feel free to suggest better wordings for the diagnostic message.
## Test Plan
I modified `mdtest/annotations/invalid.md` and added a test for each
binary operator, and fixed tests that was broken by the new diagnostic.
This PR contains the following updates:
| Package | Type | Update | Change |
|---|---|---|---|
| [astral-sh/setup-uv](https://redirect.github.com/astral-sh/setup-uv) |
action | patch | `v6.3.0` -> `v6.3.1` |
---
> [!WARNING]
> Some dependencies could not be looked up. Check the Dependency
Dashboard for more information.
---
### Release Notes
<details>
<summary>astral-sh/setup-uv (astral-sh/setup-uv)</summary>
###
[`v6.3.1`](https://redirect.github.com/astral-sh/setup-uv/releases/tag/v6.3.1):
🌈 Do not warn when version not in manifest-file
[Compare
Source](https://redirect.github.com/astral-sh/setup-uv/compare/v6.3.0...v6.3.1)
##### Changes
This is a hotfix to change the warning messages that a version could not
be found in the local manifest-file to info level.
A `setup-uv` release contains a version-manifest.json file with infos in
all available `uv` releases. When a new `uv` version is released this is
not contained in this file until the file gets updated and a new
`setup-uv` release is made.
We will overhaul this process in the future but for now the spamming of
warnings is removed.
##### 🐛 Bug fixes
- Do not warn when version not in manifest-file
[@​eifinger](https://redirect.github.com/eifinger)
([#​462](https://redirect.github.com/astral-sh/setup-uv/issues/462))
##### 🧰 Maintenance
- chore: update known versions for 0.7.14
@​[github-actions\[bot\]](https://redirect.github.com/apps/github-actions)
([#​459](https://redirect.github.com/astral-sh/setup-uv/issues/459))
- Revert "Set expected cache dir drive to C: on windows
([#​451](https://redirect.github.com/astral-sh/setup-uv/issues/451))"
[@​eifinger](https://redirect.github.com/eifinger)
([#​460](https://redirect.github.com/astral-sh/setup-uv/issues/460))
</details>
---
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This PR contains the following updates:
| Package | Type | Update | Change |
|---|---|---|---|
| [clearscreen](https://redirect.github.com/watchexec/clearscreen) |
workspace.dependencies | patch | `4.0.1` -> `4.0.2` |
---
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> Some dependencies could not be looked up. Check the Dependency
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---
### Release Notes
<details>
<summary>watchexec/clearscreen (clearscreen)</summary>
###
[`v4.0.2`](https://redirect.github.com/watchexec/clearscreen/blob/HEAD/CHANGELOG.md#v402-2025-06-25)
[Compare
Source](https://redirect.github.com/watchexec/clearscreen/compare/v4.0.1...v4.0.2)
- **Deps:** Upgrade which from 7.0.2 to 8.0.0
([#​34](https://redirect.github.com/watchexec/clearscreen/issues/34))
-
([09bc029](09bc0299f4))
</details>
---
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This PR contains the following updates:
| Package | Type | Update | Change |
|---|---|---|---|
| [ordermap](https://redirect.github.com/indexmap-rs/ordermap) |
workspace.dependencies | patch | `0.5.7` -> `0.5.8` |
---
> [!WARNING]
> Some dependencies could not be looked up. Check the Dependency
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---
### Release Notes
<details>
<summary>indexmap-rs/ordermap (ordermap)</summary>
###
[`v0.5.8`](https://redirect.github.com/indexmap-rs/ordermap/blob/HEAD/RELEASES.md#058-2025-06-26)
[Compare
Source](https://redirect.github.com/indexmap-rs/ordermap/compare/0.5.7...0.5.8)
- Added `extract_if` methods to `OrderMap` and `OrderSet`, similar to
the
methods for `HashMap` and `HashSet` with ranges like `Vec::extract_if`.
- Added more `#[track_caller]` annotations to functions that may panic.
</details>
---
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This PR contains the following updates:
| Package | Type | Update | Change |
|---|---|---|---|
| [indexmap](https://redirect.github.com/indexmap-rs/indexmap) |
workspace.dependencies | minor | `2.9.0` -> `2.10.0` |
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<summary>indexmap-rs/indexmap (indexmap)</summary>
###
[`v2.10.0`](https://redirect.github.com/indexmap-rs/indexmap/blob/HEAD/RELEASES.md#2100-2025-06-26)
[Compare
Source](https://redirect.github.com/indexmap-rs/indexmap/compare/2.9.0...2.10.0)
- Added `extract_if` methods to `IndexMap` and `IndexSet`, similar to
the
methods for `HashMap` and `HashSet` with ranges like `Vec::extract_if`.
- Added more `#[track_caller]` annotations to functions that may panic.
</details>
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## Summary
Print the [new salsa memory usage
dumps](https://github.com/astral-sh/ruff/pull/18928) in mypy primer CI
runs to help us catch memory regressions. The numbers are rounded to the
nearest power of 1.1 (about a 5% threshold between buckets) to avoid overly sensitive diffs.
This PR extracts a lot of the complex logic in the `match_parameters`
and `check_types` methods of our call binding machinery into separate
helper types. This is setup for #18996, which will update this logic to
handle variadic arguments. To do so, it is helpful to have the
per-argument logic extracted into a method that we can call repeatedly
for each _element_ of a variadic argument.
This should be a pure refactoring, with no behavioral changes.
This PR updates our unpacking assignment logic to use the new tuple
machinery. As a result, we can now unpack variable-length tuples
correctly.
As part of this, the `TupleSpec` classes have been renamed to `Tuple`,
and can now contain any element (Rust) type, not just `Type<'db>`. The
unpacker uses a tuple of `UnionBuilder`s to maintain the types that will
be assigned to each target, as we iterate through potentially many union
elements on the rhs. We also add a new consuming iterator for tuples,
and update the `all_elements` methods to wrap the result in an enum
(similar to `itertools::Position`) letting you know which part of the
tuple each element appears in. I also added a new
`UnionBuilder::try_build`, which lets you specify a different fallback
type if the union contains no elements.
