[joaoaracheski]

Description

Fixes #6377.

@control and @value use @dataclass_transform() without field_specifiers. Per the typing spec, type checkers then don't treat dataclasses.field() as a field specifier, so its arguments are ignored: a field declared with field(init=False) is still accepted as an __init__ argument. At runtime both decorators wrap dataclasses.dataclass, so field() already works there; this only aligns the static view with the runtime.

This PR adds field_specifiers=(dataclasses.field,) to both decorators.

skip_field() is intentionally not listed. It calls field(default=None, ...) internally, but checkers only see a default when the call passes default= explicitly, so listing it would turn fields declared with skip_field() into required parameters.

Test code

from dataclasses import field

import flet as ft
from flet.controls.base_control import control
from flet.controls.value_types import value


@control("MyControl")
class MyControl(ft.Control):
    internal: int = field(init=False, default=0)


@value
class MyValue:
    internal: int = field(init=False, default=0)


MyControl(internal=1)  # should be reported: `internal` is init=False
MyValue(internal=1)  # should be reported: `internal` is init=False

mypy before: no error on the last two lines.
mypy after:

error: Unexpected keyword argument "internal" for "MyControl"  [call-arg]
error: Unexpected keyword argument "internal" for "MyValue"  [call-arg]

Also added test_dataclass_transforms_declare_field_specifiers to test_base_control.py; it fails without the fix and passes with it.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist

• I signed the CLA.
• I have performed a self-review of my own code.
• My code follows the style guidelines of this project.
• I have commented my code, particularly in hard-to-understand areas.
• My changes generate no new warnings.
• New and existing tests pass locally with my changes.
• I have made corresponding documentation changes, if applicable.
• I have added changelog entries for user-facing changes, if applicable.
• I have updated release guide pages and website/sidebars.yml for breaking changes, removals, and deprecations, if applicable.

Additional details

uv run --group test pytest packages/flet/tests: 507 passed, 8 skipped. ruff check and ruff format --check are clean on the changed files.

I didn't add a changelog entry because there's no section for the next release yet. Happy to add it where you prefer, e.g. under Bug fixes:

• Fix type checkers ignoring dataclasses.field() arguments such as init=False in classes decorated with @control and @value (#6377) by @joaoaracheski.

Side note, unrelated to this PR: with @control("MyControl") mypy also reports Argument 1 has incompatible type "type[MyControl]"; expected "type[Never]" on the class line. I can open a separate issue for it if useful.

Summary by Sourcery

Align the static dataclass behavior of @control and @value with their runtime behavior by declaring dataclasses.field as a supported field specifier.

Bug Fixes:

• Ensure type checkers honor dataclasses.field() options such as init=False for classes decorated with @control and @value.],
• enhancements=[],
• build=[],
• ci=[],
• deployment=[],
• docs=[],
• tests=[

Tests:

• Add coverage verifying both decorators declare dataclasses.field as a dataclass field specifier.

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All committers have signed the CLA.

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[sourcery-ai]

Hey - I've reviewed your changes and they look great!

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[ndonkoHenri]

Thanks for your contribution! Looks good to me.

Please add a changelog entry as you suggested.