Django × Pysen × Stubs

import dataclasses
import pathlib
from typing import Any, DefaultDict, Dict, Sequence, Tuple

import dacite
from pysen.command import CommandBase
from pysen.component import ComponentBase, RunOptions
from pysen.mypy import _SettingFileName as MypySettingFileName
from pysen.plugin import PluginBase
from pysen.pyproject_model import Config, PluginConfig
from pysen.reporter import Reporter
from pysen.runner_options import PathContext
from pysen.setting import SettingFile

_SettingFileName = MypySettingFileName


class DjangoStubsCommand(CommandBase):
    def __init__(self, name: str) -> None:
        self._name = name

    @property
    def name(self) -> str:
        return self._name

    def __call__(self, reporter: Reporter) -> int:
        return 0  # do nothing, just normal end


class DjangoStubsComponent(ComponentBase):
    def __init__(self, django_settings_module: str) -> None:
        self._name = "configure django-stubs"
        self._django_settings_module = django_settings_module
        self._targets = ["lint"]

    @property
    def name(self) -> str:
        return self._name

    def export(self) -> Tuple[Sequence[str], Dict[str, Any]]:
        section_name = "mypy.plugins.django-stubs"
        entries = {"django_settings_module": self._django_settings_module}
        return [section_name], entries

    def export_settings(
        self,
        paths: PathContext,
        files: DefaultDict[str, SettingFile],
    ) -> None:
        setting_file = files[_SettingFileName]
        section, setting = self.export()
        setting_file.set_section(section, setting)

    @property
    def targets(self) -> Sequence[str]:
        return self._targets

    def create_command(
        self, target: str, paths: PathContext, options: RunOptions
    ) -> CommandBase:
        assert target in self._targets
        return DjangoStubsCommand(self._name)


@dataclasses.dataclass
class DjangoStubsPluginConfig:
    django_settings_module: str


class DjangoStubsPlugin(PluginBase):
    def load(
        self, file_path: pathlib.Path, config_data: PluginConfig, root: Config
    ) -> Sequence[ComponentBase]:
        assert (
            config_data.config is not None
        ), f"{config_data.location}.config must be not None"
        config = dacite.from_dict(
            DjangoStubsPluginConfig, config_data.config, dacite.Config(strict=True)
        )
        return [DjangoStubsComponent(config.django_settings_module)]


# NOTE: This is the entry point of a plugin method
def plugin() -> PluginBase:
    return DjangoStubsPlugin()

[mypy]
plugins =
    mypy_django_plugin.main