[ty] dataclass_transform: Support frozen_default and kw_only_default (#20761)
Some checks are pending
CI / Determine changes (push) Waiting to run
CI / cargo fmt (push) Waiting to run
CI / cargo clippy (push) Blocked by required conditions
CI / cargo test (linux) (push) Blocked by required conditions
CI / cargo test (linux, release) (push) Blocked by required conditions
CI / cargo test (windows) (push) Blocked by required conditions
CI / cargo test (wasm) (push) Blocked by required conditions
CI / cargo build (release) (push) Waiting to run
CI / cargo build (msrv) (push) Blocked by required conditions
CI / cargo fuzz build (push) Blocked by required conditions
CI / fuzz parser (push) Blocked by required conditions
CI / test scripts (push) Blocked by required conditions
CI / ecosystem (push) Blocked by required conditions
CI / Fuzz for new ty panics (push) Blocked by required conditions
CI / cargo shear (push) Blocked by required conditions
CI / ty completion evaluation (push) Blocked by required conditions
CI / python package (push) Waiting to run
CI / pre-commit (push) Waiting to run
CI / mkdocs (push) Waiting to run
CI / formatter instabilities and black similarity (push) Blocked by required conditions
CI / test ruff-lsp (push) Blocked by required conditions
CI / check playground (push) Blocked by required conditions
CI / benchmarks instrumented (ruff) (push) Blocked by required conditions
CI / benchmarks instrumented (ty) (push) Blocked by required conditions
CI / benchmarks-walltime (push) Blocked by required conditions
[ty Playground] Release / publish (push) Waiting to run

## 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>
This commit is contained in:
wangxiaolei 2025-10-09 15:34:49 +08:00 committed by GitHub
parent b0c6217e0b
commit f0d0b57900
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
2 changed files with 79 additions and 23 deletions

View file

@ -202,7 +202,7 @@ from typing import dataclass_transform
from dataclasses import field
@dataclass_transform(kw_only_default=True)
def create_model(*, init=True): ...
def create_model(*, kw_only: bool = True): ...
@create_model()
class A:
name: str
@ -213,24 +213,69 @@ a = A(name="Harry")
a = A("Harry")
```
TODO: This can be overridden by the call to the decorator function.
This can be overridden by setting `kw_only=False` when applying the decorator:
```py
from typing import dataclass_transform
@dataclass_transform(kw_only_default=True)
def create_model(*, kw_only: bool = True): ...
@create_model(kw_only=False)
class CustomerModel:
id: int
name: str
# TODO: Should not emit errors
# error: [missing-argument]
# error: [too-many-positional-arguments]
c = CustomerModel(1, "Harry")
```
### `frozen_default`
When provided, sets the default value for the `frozen` parameter of `field()`.
```py
from typing import dataclass_transform
@dataclass_transform(frozen_default=True)
def create_model(*, frozen: bool = True): ...
@create_model()
class ImmutableModel:
name: str
i = ImmutableModel(name="test")
i.name = "new" # error: [invalid-assignment]
```
Again, this can be overridden by setting `frozen=False` when applying the decorator:
```py
@create_model(frozen=False)
class MutableModel:
name: str
m = MutableModel(name="test")
m.name = "new" # No error
```
### Combining parameters
Combining several of these parameters also works as expected:
```py
from typing import dataclass_transform
@dataclass_transform(eq_default=True, order_default=False, kw_only_default=True, frozen_default=True)
def create_model(*, eq: bool = True, order: bool = False, kw_only: bool = True, frozen: bool = True): ...
@create_model(eq=False, order=True, kw_only=False, frozen=False)
class OverridesAllParametersModel:
name: str
age: int
# Positional arguments are allowed:
model = OverridesAllParametersModel("test", 25)
# Mutation is allowed:
model.name = "new" # No error
# Comparison methods are generated:
model < model # No error
```
### `field_specifiers`
To do

View file

@ -1023,18 +1023,30 @@ impl<'db> Bindings<'db> {
let mut dataclass_params =
DataclassParams::from(params);
if let Some(Some(Type::BooleanLiteral(order))) =
overload
.signature
.parameters()
.keyword_by_name("order")
.map(|(idx, _)| idx)
.and_then(|idx| {
overload.parameter_types().get(idx)
})
if let Ok(Some(Type::BooleanLiteral(order))) =
overload.parameter_type_by_name("order")
{
dataclass_params.set(DataclassParams::ORDER, order);
}
if let Ok(Some(Type::BooleanLiteral(eq))) =
overload.parameter_type_by_name("eq")
{
dataclass_params.set(DataclassParams::EQ, eq);
}
if let Ok(Some(Type::BooleanLiteral(kw_only))) =
overload.parameter_type_by_name("kw_only")
{
dataclass_params
.set(DataclassParams::ORDER, *order);
.set(DataclassParams::KW_ONLY, kw_only);
}
if let Ok(Some(Type::BooleanLiteral(frozen))) =
overload.parameter_type_by_name("frozen")
{
dataclass_params
.set(DataclassParams::FROZEN, frozen);
}
Type::DataclassDecorator(dataclass_params)
@ -2933,12 +2945,11 @@ impl<'db> Binding<'db> {
&self,
parameter_name: &str,
) -> Result<Option<Type<'db>>, UnknownParameterNameError> {
let (index, _) = self
let index = self
.signature
.parameters()
.iter()
.enumerate()
.find(|(_, param)| param.name().is_some_and(|name| name == parameter_name))
.keyword_by_name(parameter_name)
.map(|(i, _)| i)
.ok_or(UnknownParameterNameError)?;
Ok(self.parameter_tys[index])