Commit Graph

25 Commits

Author SHA1 Message Date
David Peter 3c229ae58a
[ty] `dataclass_transform`: Support for fields with an `alias` (#20961)
## Summary

closes https://github.com/astral-sh/ty/issues/1385

## Conformance tests

Two false positives removed, as expected.

## Test Plan

New Markdown tests
2025-10-18 18:20:39 +00:00
David Peter cfbd42c22a
[ty] Support `dataclass_transform` for base class models (#20783)
## 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.
2025-10-17 14:04:31 +02:00
Ibraheem Ahmed 1ade4f2081
[ty] Avoid unnecessarily widening generic specializations (#20875)
## 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.
2025-10-16 19:17:37 +00:00
David Peter 8dad58de37
[ty] Support dataclass-transform `field_specifiers` (#20888)
## 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.
2025-10-16 20:49:11 +02:00
David Peter c8133104e8
[ty] Use field-specifier return type as the default type for the field (#20915)
## 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.
2025-10-16 13:13:45 +02:00
David Peter 0cc663efcd
[ty] Do not assume that `field`s have a default value (#20914)
## Summary

fixes https://github.com/astral-sh/ty/issues/1366

## Test Plan

Added regression test
2025-10-16 12:49:24 +02:00
David Peter 195e8f0684
[ty] Treat functions, methods, and dynamic types as function-like `Callable`s (#20842)
## Summary

Treat functions, methods, and dynamic types as function-like `Callable`s

closes https://github.com/astral-sh/ty/issues/1342
closes https://github.com/astral-sh/ty/issues/1344

## Ecosystem analysis

All removed diagnostics look like cases of
https://github.com/astral-sh/ty/issues/1344

## Test Plan

Added regression test
2025-10-13 15:21:55 +02:00
Alex Waygood 7064c38e53
[ty] Filter out `revealed-type` and `undefined-reveal` diagnostics from mdtest snapshots (#20820) 2025-10-12 18:39:32 +00:00
David Peter ae83a1fd2d
[ty] Additional tests for `dataclass_transform` (class-level overwrites, `field_specifiers`) (#20788)
## Summary

Adds a set of basic new tests corresponding to open points in
https://github.com/astral-sh/ty/issues/1327, to document the state of
support for `dataclass_transform`.
2025-10-10 11:22:06 +00:00
David Peter 75f3c0e8e6
[ty] Respect `dataclass_transform` parameters for metaclass-based models (#20780)
## Summary

Respect parameters such as `frozen_default` for metaclass-based
`@dataclass_transformer` models.

Related to: https://github.com/astral-sh/ty/issues/1260

## Typing conformance changes

Those are all correct (new true positives)

## Test Plan

New Markdown tests
2025-10-09 13:24:20 +00:00
wangxiaolei f0d0b57900
[ty] `dataclass_transform`: Support `frozen_default` and `kw_only_default` (#20761)
## Summary

- Add support for eq, kw_only, and frozen parameter overrides in
@dataclass_transform
- Previously only order parameter override was supported
- Update test documentation to reflect fixed behavior
- Resolves issue where kw_only_default and frozen_default could not be
overridden

closes https://github.com/astral-sh/ty/issues/1260

## Test Plan

New Markdown tests

---------

Co-authored-by: David Peter <mail@david-peter.de>
2025-10-09 09:34:49 +02:00
David Peter 1f1542db51
[ty] Use 3.14 as the default version (#20759)
## Summary

Bump the latest supported Python version of ty to 3.14 and updates some
references from 3.13 to 3.14.

This also fixes a bug with `dataclasses.field` on 3.14 (which adds a new
keyword-only parameter to that function, breaking our previously naive
matching on the parameter structure of that function).

## Test Plan

A `ty check` on a file with template strings (without any further
configuration) doesn't raise errors anymore.
2025-10-08 11:38:47 +02:00
justin 08fcf7e106
[ty] initial support for `slots=True` in dataclasses (#20278) 2025-09-07 18:25:35 +01:00
Leandro Braga 39ee71c2a5
[ty] correctly ignore field specifiers when not specified (#20002)
This commit corrects the type checker's behavior when handling
`dataclass_transform` decorators that don't explicitly specify
`field_specifiers`. According to [PEP 681 (Data Class
Transforms)](https://peps.python.org/pep-0681/#dataclass-transform-parameters),
when `field_specifiers` is not provided, it defaults to an empty tuple,
meaning no field specifiers are supported and
`dataclasses.field`/`dataclasses.Field` calls should be ignored.

Fixes https://github.com/astral-sh/ty/issues/980
2025-08-20 11:33:23 -07:00
Eric Jolibois 58efd19f11
[ty] apply `KW_ONLY` sentinel only to local fields (#19986)
fix https://github.com/astral-sh/ty/issues/1047

## Summary

This PR fixes how `KW_ONLY` is applied in dataclasses. Previously, the
sentinel leaked into subclasses and incorrectly marked their fields as
keyword-only; now it only affects fields declared in the same class.

```py
from dataclasses import dataclass, KW_ONLY

@dataclass
class D:
    x: int
    _: KW_ONLY
    y: str

@dataclass
class E(D):
    z: bytes

# This should work: x=1 (positional), z=b"foo" (positional), y="foo" (keyword-only)
E(1, b"foo", y="foo")

reveal_type(E.__init__)  # revealed: (self: E, x: int, z: bytes, *, y: str) -> None
```

<!-- What's the purpose of the change? What does it do, and why? -->

## Test Plan

<!-- How was it tested? -->
mdtests
2025-08-19 11:01:35 -07:00
justin dc2e8ab377
[ty] support `kw_only=True` for `dataclass()` and `field()` (#19677)
## Summary
https://github.com/astral-sh/ty/issues/111

adds support for `@dataclass(kw_only=True)`
(https://docs.python.org/3/library/dataclasses.html)

## Test Plan
- new mdtests
- triaged conformance diffs (notes here:
https://diffswarm.dev/d-01k2gknwyq82f6x17zqf3apjxc)
- `mypy_primer` no-op
2025-08-14 08:02:55 -07:00
David Peter d4eb4277ad
[ty] Add basic support for `dataclasses.field` (#19553)
## Summary

Add basic support for `dataclasses.field`:
* remove fields with `init=False` from the signature of the synthesized
`__init__` method
* infer correct default value types from `default` or `default_factory`
arguments

```py
from dataclasses import dataclass, field

def default_roles() -> list[str]:
    return ["user"]

@dataclass
class Member:
    name: str
    roles: list[str] = field(default_factory=default_roles)
    tag: str | None = field(default=None, init=False)

# revealed: (self: Member, name: str, roles: list[str] = list[str]) -> None
reveal_type(Member.__init__)
```

Support for `kw_only` has **not** been added.

part of https://github.com/astral-sh/ty/issues/111

## Test Plan

New Markdown tests
2025-07-25 14:56:04 +02:00
David Peter fcdffe4ac9
[ty] Pass down specialization to generic dataclass bases (#19472)
## Summary

closes https://github.com/astral-sh/ty/issues/853

## Test Plan

Regression test
2025-07-21 20:51:58 +02:00
David Peter b6579eaf04
[ty] Disallow assignment to `Final` class attributes (#19457)
## Summary

Emit errors for the following assignments:
```py
class C:
    CLASS_LEVEL_CONSTANT: Final[int] = 1

C.CLASS_LEVEL_CONSTANT = 2
C().CLASS_LEVEL_CONSTANT = 2
```

## Test Plan

Updated and new MD tests
2025-07-21 14:27:56 +02:00
justin 39b41838f3
[ty] synthesize __setattr__ for frozen dataclasses (#19307)
## Summary

Synthesize a `__setattr__` method with a return type of `Never` for
frozen dataclasses.

https://docs.python.org/3/library/dataclasses.html#frozen-instances

https://docs.python.org/3/library/dataclasses.html#dataclasses.FrozenInstanceError

### Related
https://github.com/astral-sh/ty/issues/111
https://github.com/astral-sh/ruff/pull/17974#discussion_r2108527106
https://github.com/astral-sh/ruff/pull/18347#discussion_r2128174665

## Test Plan

New Markdown tests

---------

Co-authored-by: David Peter <mail@david-peter.de>
2025-07-18 11:35:05 +02:00
David Peter a1edb69ea5
[ty] Enum literal types (#19328)
## Summary

Add a new `Type::EnumLiteral(…)` variant and infer this type for member
accesses on enums.

**Example**: No more `@Todo` types here:
```py
from enum import Enum

class Answer(Enum):
    YES = 1
    NO = 2

    def is_yes(self) -> bool:
        return self == Answer.YES

reveal_type(Answer.YES)  # revealed: Literal[Answer.YES]
reveal_type(Answer.YES == Answer.NO)  # revealed: Literal[False]
reveal_type(Answer.YES.is_yes())  # revealed: bool
```

## Test Plan

* Many new Markdown tests for the new type variant
* Added enum literal types to property tests, ran property tests

## Ecosystem analysis

Summary:

Lots of false positives removed. All of the new diagnostics are
either new true positives (the majority) or known problems. Click for
detailed analysis</summary>

Details:

```diff
AutoSplit (https://github.com/Toufool/AutoSplit)
+ error[call-non-callable] src/capture_method/__init__.py:137:9: Method `__getitem__` of type `bound method CaptureMethodDict.__getitem__(key: Never, /) -> type[CaptureMethodBase]` is not callable on object of type `CaptureMethodDict`
+ error[call-non-callable] src/capture_method/__init__.py:147:9: Method `__getitem__` of type `bound method CaptureMethodDict.__getitem__(key: Never, /) -> type[CaptureMethodBase]` is not callable on object of type `CaptureMethodDict`
+ error[call-non-callable] src/capture_method/__init__.py:148:1: Method `__getitem__` of type `bound method CaptureMethodDict.__getitem__(key: Never, /) -> type[CaptureMethodBase]` is not callable on object of type `CaptureMethodDict`
```

New true positives. That `__getitem__` method is apparently annotated
with `Never` to prevent developers from using it.


```diff
dd-trace-py (https://github.com/DataDog/dd-trace-py)
+ error[invalid-assignment] ddtrace/vendor/psutil/_common.py:29:5: Object of type `None` is not assignable to `Literal[AddressFamily.AF_INET6]`
+ error[invalid-assignment] ddtrace/vendor/psutil/_common.py:33:5: Object of type `None` is not assignable to `Literal[AddressFamily.AF_UNIX]`
```

Arguably true positives:
e0a772c28b/ddtrace/vendor/psutil/_common.py (L29)

```diff
ignite (https://github.com/pytorch/ignite)
+ error[invalid-argument-type] tests/ignite/engine/test_custom_events.py:190:34: Argument to bound method `__call__` is incorrect: Expected `((...) -> Unknown) | None`, found `Literal["123"]`
+ error[invalid-argument-type] tests/ignite/engine/test_custom_events.py:220:37: Argument to function `default_event_filter` is incorrect: Expected `Engine`, found `None`
+ error[invalid-argument-type] tests/ignite/engine/test_custom_events.py:220:43: Argument to function `default_event_filter` is incorrect: Expected `int`, found `None`
+ error[call-non-callable] tests/ignite/engine/test_custom_events.py:561:9: Object of type `CustomEvents` is not callable
+ error[invalid-argument-type] tests/ignite/metrics/test_frequency.py:50:38: Argument to bound method `attach` is incorrect: Expected `Events`, found `CallableEventWithFilter`
```

All true positives. Some of them are inside `pytest.raises(TypeError,
…)` blocks 🙃

```diff
meson (https://github.com/mesonbuild/meson)
+ error[invalid-argument-type] unittests/internaltests.py:243:51: Argument to bound method `__init__` is incorrect: Expected `bool`, found `Literal[MachineChoice.HOST]`
+ error[invalid-argument-type] unittests/internaltests.py:271:51: Argument to bound method `__init__` is incorrect: Expected `bool`, found `Literal[MachineChoice.HOST]`
```

New true positives. Enum literals can not be assigned to `bool`, even if
their value types are `0` and `1`.

```diff
poetry (https://github.com/python-poetry/poetry)
+ error[invalid-assignment] src/poetry/console/exceptions.py:101:5: Object of type `Literal[""]` is not assignable to `InitVar[str]`
```

New false positive, missing support for `InitVar`.

```diff
prefect (https://github.com/PrefectHQ/prefect)
+ error[invalid-argument-type] src/integrations/prefect-dask/tests/test_task_runners.py:193:17: Argument is incorrect: Expected `StateType`, found `Literal[StateType.COMPLETED]`
```

This is confusing. There are two definitions
([one](74d8cd93ee/src/prefect/client/schemas/objects.py (L89-L100)),
[two](https://github.com/PrefectHQ/prefect/blob/main/src/prefect/server/schemas/states.py#L40))
of the `StateType` enum. Here, we're trying to assign one to the other.
I don't think that should be allowed, so this is a true positive (?).

```diff
python-htmlgen (https://github.com/srittau/python-htmlgen)
+ error[invalid-assignment] test_htmlgen/form.py:51:9: Object of type `str` is not assignable to attribute `autocomplete` of type `Autocomplete | None`
+ error[invalid-assignment] test_htmlgen/video.py:38:9: Object of type `str` is not assignable to attribute `preload` of type `Preload | None`
```

True positives. [The stubs are
wrong](01e3b911ac/htmlgen/form.pyi (L8-L10)).
These should not contain type annotations, but rather just `OFF = ...`.

```diff
rotki (https://github.com/rotki/rotki)
+ error[invalid-argument-type] rotkehlchen/tests/unit/test_serialization.py:62:30: Argument to bound method `deserialize` is incorrect: Expected `str`, found `Literal[15]`
```

New true positive.

```diff
vision (https://github.com/pytorch/vision)
+ error[unresolved-attribute] test/test_extended_models.py:302:17: Type `type[WeightsEnum]` has no attribute `DEFAULT`
+ error[unresolved-attribute] test/test_extended_models.py:302:58: Type `type[WeightsEnum]` has no attribute `DEFAULT`
```

Also new true positives. No `DEFAULT` member exists on `WeightsEnum`.
2025-07-15 21:31:53 +02:00
David Peter 68106dd631
[ty] `dataclasses.field` support (#19140)
## Summary

Add an initial set of tests for `dataclasses.field`.
2025-07-09 09:18:08 +02:00
David Peter ce2bdb9357
[ty] Conditionally defined dataclass fields (#19197)
## Summary

Fixes a bug where conditionally defined dataclass fields were previously
ignored.

Thanks to @lipefree for reporting this.

## Test Plan

New Markdown tests
2025-07-08 16:16:50 +02:00
David Peter 9a4b85d845
[ty] Add tests for dataclass fields annotated with `Final` (#19202)
## Summary

Adds some tests for dataclass fields that are annotated with `Final`
(see comment
[here](https://github.com/astral-sh/ruff/pull/15768#issuecomment-3044737645)).
Turns out that nothing is needed here, everything already works as
expected (apart from the fact that we can assign to `Final` fields,
which is tracked in https://github.com/astral-sh/ty/issues/158

## Test Plan

New Markdown tests
2025-07-08 12:33:46 +00:00
David Peter e212dc2e8e
[ty] Restructure/move dataclass tests (#19117)
Before I'm adding even more dataclass-related files, let's organize them
in a separate folder.
2025-07-03 10:36:14 +00:00