Class Plugin

mypy/plugin.py:521–809

Base class of all type checker plugins. This defines a no-op plugin. Subclasses can override some methods to provide some actual functionality. All get_ methods are treated as pure functions (you should assume that results might be cached). A plugin should return None from a get_

@mypyc_attr(allow_interpreted_subclasses=True)
class Plugin(CommonPluginApi):
    """Base class of all type checker plugins.

    This defines a no-op plugin.  Subclasses can override some methods to
    provide some actual functionality.

    All get_ methods are treated as pure functions (you should assume that
    results might be cached). A plugin should return None from a get_ method
    to give way to other plugins.

    Look at the comments of various *Context objects for additional information on
    various hooks.
    """

    def __init__(self, options: Options) -> None:
        self.options = options
        self.python_version = options.python_version
        # This can't be set in __init__ because it is executed too soon in build.py.
        # Therefore, build.py *must* set it later before graph processing starts
        # by calling set_modules().
        self._modules: dict[str, MypyFile] | None = None

    def set_modules(self, modules: dict[str, MypyFile]) -> None:
        self._modules = modules

    def lookup_fully_qualified(self, fullname: str) -> SymbolTableNode | None:
        assert self._modules is not None
        return lookup_fully_qualified(fullname, self._modules)

    def report_config_data(self, ctx: ReportConfigContext) -> Any:
        """Get representation of configuration data for a module.

        The data must be encodable as JSON and will be stored in the
        cache metadata for the module. A mismatch between the cached
        values and the returned will result in that module's cache
        being invalidated and the module being rechecked.

        This can be called twice for each module, once after loading
        the cache to check if it is valid and once while writing new
        cache information.

        If is_check in the context is true, then the return of this
        call will be checked against the cached version. Otherwise the
        call is being made to determine what to put in the cache. This
        can be used to allow consulting extra cache files in certain
        complex situations.

        This can be used to incorporate external configuration information
        that might require changes to typechecking.
        """
        return None

    def get_additional_deps(self, file: MypyFile) -> list[tuple[int, str, int]]:
        """Customize dependencies for a module.

        This hook allows adding in new dependencies for a module. It
        is called after parsing a file but before analysis. This can
        be useful if a library has dependencies that are dynamic based