## Summary
Fixes#20774 by tracking whether an `InterpolatedStringState` element is
nested inside of another interpolated element. This feels like kind of a
naive fix, so I'm welcome to other ideas. But it resolves the problem in
the issue and clears up the syntax error in the black compatibility
test, without affecting many other cases.
The other affected case is actually interesting too because the
[input](96b156303b/crates/ruff_python_formatter/resources/test/fixtures/ruff/expression/fstring.py (L707))
is invalid, but the previous quote selection fixed the invalid syntax:
```pycon
Python 3.11.13 (main, Sep 2 2025, 14:20:25) [Clang 20.1.4 ] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> f'{1: abcd "{'aa'}" }' # input
File "<stdin>", line 1
f'{1: abcd "{'aa'}" }'
^^
SyntaxError: f-string: expecting '}'
>>> f'{1: abcd "{"aa"}" }' # old output
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: Invalid format specifier ' abcd "aa" ' for object of type 'int'
>>> f'{1: abcd "{'aa'}" }' # new output
File "<stdin>", line 1
f'{1: abcd "{'aa'}" }'
^^
SyntaxError: f-string: expecting '}'
```
We now preserve the invalid syntax in the input.
Unfortunately, this also seems to be another edge case I didn't consider
in https://github.com/astral-sh/ruff/pull/20867 because we don't flag
this as a syntax error after 0.14.1:
<details><summary>Shell output</summary>
<p>
```
> uvx ruff@0.14.0 check --ignore ALL --target-version py311 - <<EOF
f'{1: abcd "{'aa'}" }'
EOF
invalid-syntax: Cannot reuse outer quote character in f-strings on Python 3.11 (syntax was added in Python 3.12)
--> -:1:14
|
1 | f'{1: abcd "{'aa'}" }'
| ^
|
Found 1 error.
> uvx ruff@0.14.1 check --ignore ALL --target-version py311 - <<EOF
f'{1: abcd "{'aa'}" }'
EOF
All checks passed!
> uvx python@3.11 -m ast <<EOF
f'{1: abcd "{'aa'}" }'
EOF
Traceback (most recent call last):
File "<frozen runpy>", line 198, in _run_module_as_main
File "<frozen runpy>", line 88, in _run_code
File "/home/brent/.local/share/uv/python/cpython-3.11.13-linux-x86_64-gnu/lib/python3.11/ast.py", line 1752, in <module>
main()
File "/home/brent/.local/share/uv/python/cpython-3.11.13-linux-x86_64-gnu/lib/python3.11/ast.py", line 1748, in main
tree = parse(source, args.infile.name, args.mode, type_comments=args.no_type_comments)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/brent/.local/share/uv/python/cpython-3.11.13-linux-x86_64-gnu/lib/python3.11/ast.py", line 50, in parse
return compile(source, filename, mode, flags,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "<stdin>", line 1
f'{1: abcd "{'aa'}" }'
^^
SyntaxError: f-string: expecting '}'
```
</p>
</details>
I assumed that was the same `ParseError` as the one caused by
`f"{1:""}"`, but this is a nested interpolation inside of the format
spec.
## Test Plan
New test copied from the black compatibility test. I guess this is a
duplicate now, I started working on this branch before the new black
tests were imported, so I could delete the separate test in our fixtures
if that's preferable.
## Summary
Support `dataclass_transform` when used on a (base) class.
## Typing conformance
* The changes in `dataclasses_transform_class.py` look good, just a few
mistakes due to missing `alias` support.
* I didn't look closely at the changes in
`dataclasses_transform_converter.py` since we don't support `converter`
yet.
## Ecosystem impact
The impact looks huge, but it's concentrated on a single project (ibis).
Their setup looks more or less like this:
* the real `Annotatable`:
d7083c2c96/ibis/common/grounds.py (L100-L101)
* the real `DataType`:
d7083c2c96/ibis/expr/datatypes/core.py (L161-L179)
* the real `Array`:
d7083c2c96/ibis/expr/datatypes/core.py (L1003-L1006)
```py
from typing import dataclass_transform
@dataclass_transform()
class Annotatable:
pass
class DataType(Annotatable):
nullable: bool = True
class Array[T](DataType):
value_type: T
```
They expect something like `Array([1, 2])` to work, but ty, pyright,
mypy, and pyrefly would all expect there to be a first argument for the
`nullable` field on `DataType`. I don't really understand on what
grounds they expect the `nullable` field to be excluded from the
signature, but this seems to be the main reason for the new diagnostics
here. Not sure if related, but it looks like their typing setup is not
really complete
(https://github.com/ibis-project/ibis/issues/6844#issuecomment-1868274770,
this thread also mentions `dataclass_transform`).
## Test Plan
Update pre-existing tests.
Detect legacy namespace packages and treat them like namespace packages
when looking them up as the *parent* of the module we're interested in.
In all other cases treat them like a regular package.
(This PR is coauthored by @MichaReiser in a shared coding session)
Fixes https://github.com/astral-sh/ty/issues/838
---------
Co-authored-by: Micha Reiser <micha@reiser.io>
## Summary
Prefer the declared type for collection literals, e.g.,
```py
x: list[Any] = [1, "2", (3,)]
reveal_type(x) # list[Any]
```
This solves a large part of https://github.com/astral-sh/ty/issues/136
for invariant generics, where respecting the declared type is a lot more
important. It also means that annotated dict literals with `dict[_,
Any]` is a way out of https://github.com/astral-sh/ty/issues/1248.
We have to track whether a typevar appears in a position where it's
inferable or not. In a non-inferable position (in the body of the
generic class or function that binds it), assignability must hold for
every possible specialization of the typevar. In an inferable position,
it only needs to hold for _some_ specialization.
https://github.com/astral-sh/ruff/pull/20093 is working on using
constraint sets to model assignability of typevars, and the constraint
sets that we produce will be the same for inferable vs non-inferable
typevars; what changes is what we _compare_ that constraint set to. (For
a non-inferable typevar, the constraint set must equal the set of valid
specializations; for an inferable typevar, it must not be `never`.)
When I first added support for tracking inferable vs non-inferable
typevars, it seemed like it would be easiest to have separate `Type`
variants for each. The alternative (which lines up with the Δ set in
[POPL15](https://doi.org/10.1145/2676726.2676991)) would be to
explicitly plumb through a list of inferable typevars through our type
property methods. That seemed cumbersome.
In retrospect, that was the wrong decision. We've had to jump through
hoops to translate types between the inferable and non-inferable
variants, which has been quite brittle. Combined with the original point
above, that much of the assignability logic will become more identical
between inferable and non-inferable, there is less justification for the
two `Type` variants. And plumbing an extra `inferable` parameter through
all of these methods turns out to not be as bad as I anticipated.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
Use the declared type of variables as type context for the RHS of assignment expressions, e.g.,
```py
x: list[int | str]
x = [1]
reveal_type(x) # revealed: list[int | str]
```
## Summary
Ignore the type context when specializing a generic call if it leads to
an unnecessarily wide return type. For example, [the example mentioned
here](https://github.com/astral-sh/ruff/pull/20796#issuecomment-3403319536)
works as expected after this change:
```py
def id[T](x: T) -> T:
return x
def _(i: int):
x: int | None = id(i)
y: int | None = i
reveal_type(x) # revealed: int
reveal_type(y) # revealed: int
```
I also added extended our usage of `filter_disjoint_elements` to tuple
and typed-dict inference, which resolves
https://github.com/astral-sh/ty/issues/1266.
## Summary
Add support for the `field_specifiers` parameter on
`dataclass_transform` decorator calls.
closes https://github.com/astral-sh/ty/issues/1068
## Conformance test results
All true positives ✔️
## Ecosystem analysis
* `trio`: this is the kind of change that I would expect from this PR.
The code makes use of a dataclass `Outcome` with a `_unwrapped: bool =
attr.ib(default=False, eq=False, init=False)` field that is excluded
from the `__init__` signature, so we now see a bunch of
constructor-call-related errors going away.
* `home-assistant/core`: They have a `domain: str = attr.ib(init=False,
repr=False)` field and then use
```py
@domain.default
def _domain_default(self) -> str:
# …
```
This accesses the `default` attribute on `dataclasses.Field[…]` with a
type of `default: _T | Literal[_MISSING_TYPE.MISSING]`, so we get those
"Object of type `_MISSING_TYPE` is not callable" errors. I don't really
understand how that is supposed to work. Even if `_MISSING_TYPE` would
be absent from that union, what does this try to call? pyright also
issues an error and it doesn't seem to work at runtime? So this looks
like a true positive?
* `attrs`: Similar here. There are some new diagnostics on code that
tries to access `.validator` on a field. This *does* work at runtime,
but I'm not sure how that is supposed to type-check (without a [custom
plugin](2c6c395935/mypy/plugins/attrs.py (L575-L602))).
pyright errors on this as well.
* A handful of new false positives because we don't support `alias` yet
## Test Plan
Updated tests.
Summary
--
This PR unifies the two different ways Ruff and ty construct syntax
errors. Ruff has been storing the primary message in the diagnostic
itself, while ty attached the message to the primary annotation:
```
> ruff check try.py
invalid-syntax: name capture `x` makes remaining patterns unreachable
--> try.py:2:10
|
1 | match 42:
2 | case x: ...
| ^
3 | case y: ...
|
Found 1 error.
> uvx ty check try.py
WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
Checking ------------------------------------------------------------ 1/1 files
error[invalid-syntax]
--> try.py:2:10
|
1 | match 42:
2 | case x: ...
| ^ name capture `x` makes remaining patterns unreachable
3 | case y: ...
|
Found 1 diagnostic
```
I think there are benefits to both approaches, and I do like ty's
version, but I feel like we should pick one (and it might help with
#20901 eventually). I slightly prefer Ruff's version, so I went with
that. Hopefully this isn't too controversial, but I'm happy to close
this if it is.
Note that this shouldn't change any other diagnostic formats in ty
because
[`Diagnostic::primary_message`](98d27c4128/crates/ruff_db/src/diagnostic/mod.rs (L177))
was already falling back to the primary annotation message if the
diagnostic message was empty. As a result, I think this change will
partially resolve the FIXME therein.
Test Plan
--
Existing tests with updated snapshots
## Summary
Implement `docstring-extraneous-parameter` (`DOC102`). This rule checks
that all parameters present in a functions docstring are also present in
its signature.
Split from #13280, per this
[comment](https://github.com/astral-sh/ruff/pull/13280#issuecomment-3280575506).
Part of #12434.
## Test Plan
Test cases added.
---------
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
This is the ultra-minimal implementation of
* https://github.com/astral-sh/ty/issues/296
that was previously discussed as a good starting point. In particular we
don't actually bother trying to figure out the exact python versions,
but we still mention "hey btw for No Reason At All... you're on python
3.10" when you try to access something that has a definition rooted in
the stdlib that we believe exists sometimes.
This is a drive-by improvement that I stumbled backwards into while
looking into
* https://github.com/astral-sh/ty/issues/296
I was writing some simple tests for "thing not in old version of stdlib"
diagnostics and checked what was added in 3.14, and saw
`compression.zstd` and to my surprise discovered that `import
compression.zstd` and `from compression import zstd` had completely
different quality diagnostics.
This is because `compression` and `compression.zstd` were *both*
introduced in 3.14, and so per VERSIONS policy only an entry for
`compression` was added, and so we don't actually have any definite info
on `compression.zstd` and give up on producing a diagnostic. However the
`from compression import zstd` form fails on looking up `compression`
and we *do* have an exact match for that, so it gets a better
diagnostic!
(aside: I have now learned about the VERSIONS format and I *really* wish
they would just enumerate all the submodules but, oh well!)
The fix is, when handling an import failure, if we fail to find an exact
match *we requery with the parent module*. In cases like
`compression.zstd` this lets us at least identify that, hey, not even
`compression` exists, and luckily that fixes the whole issue. In cases
where the parent module and submodule were introduced at different times
then we may discover that the parent module is in-range and that's fine,
we don't produce the richer stdlib diagnostic.
## Summary
`dataclasses.field` and field-specifier functions of commonly used
libraries like `pydantic`, `attrs`, and `SQLAlchemy` all return the
default type for the field (or `Any`) instead of an actual `Field`
instance, even if this is not what happens at runtime. Let's make use of
this fact and assume that *all* field specifiers return the type of the
default value of the field.
For standard dataclasses, this leads to more or less the same outcome
(see test diff for details), but this change is important for 3rd party
dataclass-transformers.
## Test Plan
Tested the consequences of this change on the field-specifiers branch as
well.
## Summary
Resolves https://github.com/astral-sh/ty/issues/1349.
Fix match statement value patterns to use equality comparison semantics
instead of incorrectly narrowing to literal types directly. Value
patterns use equality for matching, and equality can be overridden, so
we can't always narrow to the matched literal.
## Test Plan
Updated match.md with corrected expected types and an additional example
with explanation
---------
Co-authored-by: David Peter <mail@david-peter.de>
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
This PR implements `F702`
https://docs.astral.sh/ruff/rules/continue-outside-loop/ as semantic
syntax error.
## Test Plan
<!-- How was it tested? -->
Tests are already previously written in F702
---------
Signed-off-by: 11happy <soni5happy@gmail.com>
Douglas Creager
Brent Westbrook
David Peter
Mark Z. Ding
Alex Waygood
Micha Reiser
Aria Desires
Ibraheem Ahmed
Dylan
Auguste Lalande
Carl Meyer
Eric Mark Martin
Justin Su
Emil Sadek
Bhuminjay Soni