Class DeduperReloader

IPython/extensions/deduperreload/deduperreload.py:174–640

This version of autoreload detects when we can leverage targeted recompilation of a subset of a module and patching existing function/method objects to reflect these changes. Detects what functions/methods can be reloaded by recursively comparing the old/new AST of module-level classes

class DeduperReloader(DeduperReloaderPatchingMixin):
    """
    This version of autoreload detects when we can leverage targeted recompilation of a subset of a module and patching
    existing function/method objects to reflect these changes.

    Detects what functions/methods can be reloaded by recursively comparing the old/new AST of module-level classes,
    module-level classes' methods, recursing through nested classes' methods. If other changes are made, original
    autoreload algorithm is called directly.
    """

    def __init__(self) -> None:
        self._to_autoreload: AutoreloadTree = AutoreloadTree()
        self.source_by_modname: dict[str, str] = {}
        self.dependency_graph: dict[tuple[str, ...], list[DependencyNode]] = {}
        self._enabled = True

    @property
    def enabled(self) -> bool:
        return self._enabled and platform.python_implementation() == "CPython"

    @enabled.setter
    def enabled(self, value: bool) -> None:
        self._enabled = value

    def update_sources(self) -> None:
        """
        Update dictionary source_by_modname with current modules' source codes.
        """
        if not self.enabled:
            return
        for new_modname in sys.modules.keys() - self.source_by_modname.keys():
            new_module = sys.modules[new_modname]
            if (
                (fname := get_module_file_name(new_module)) is None
                or "site-packages" in fname
                or "dist-packages" in fname
                or not os.access(fname, os.R_OK)
            ):
                self.source_by_modname[new_modname] = ""
                continue
            # Skip binary files (e.g., .so, .pyd, .pyo)
            if not fname.endswith(".py"):
                self.source_by_modname[new_modname] = ""
                continue
            try:
                # tokenize.open honors PEP 263 coding cookies and defaults
                # to utf-8, like the import system does.
                with tokenize.open(fname) as f:
                    self.source_by_modname[new_modname] = f.read()
            except Exception as e:
                logger = logging.getLogger("autoreload")
                logger.exception(
                    f"Failed to read module file '{fname}' for module '{new_modname}': {type(e).__name__}"
                )
                self.source_by_modname[new_modname] = ""

    constexpr_detector = ConstexprDetector()