-
Notifications
You must be signed in to change notification settings - Fork 15
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
[ENH] refactor
_clone to a plugin structure (#381)
This PR refactors the current `_clone` logic, which had a lot of if/else case distinctions (as in the `sklearn` native code) to a list of plugins that can be extended. Above the refactor, it also adds a `sklearn` specific plugin that dispatches to `sklearn` clone, ensuring that configs get cloned as well. An approach to sktime/sktime#7333, which would be solved directly after update. An alternative to #380, with advantages: * `sklearn` compatibility is automatic, for any dependency of `skbase` * the plugins can later be extended easily, for instance in a case like the missing `dict` support A test for sktime/sktime#7333, namely that output configs are retained in `sklearn` objects, has been added.
- Loading branch information
Showing
6 changed files
with
410 additions
and
111 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,129 @@ | ||
| # -*- coding: utf-8 -*- | ||
| # copyright: skbase developers, BSD-3-Clause License (see LICENSE file) | ||
| # Elements of BaseObject reuse code developed in scikit-learn. These elements | ||
| # are copyrighted by the scikit-learn developers, BSD-3-Clause License. For | ||
| # conditions see https://github.com/scikit-learn/scikit-learn/blob/main/COPYING | ||
| """Logic and plugins for cloning objects. | ||
| This module contains logic for cloning objects: | ||
| _clone(estimator, *, safe=True, plugins=None) - central entry point for cloning | ||
| _check_clone(original, clone) - validation utility to check clones | ||
| Default plugins for _clone are stored in _clone_plugins: | ||
| DEFAULT_CLONE_PLUGINS - list with default plugins for cloning | ||
| Each element of DEFAULT_CLONE_PLUGINS inherits from BaseCloner, with methods: | ||
| * check(obj) -> boolean - fast checker whether plugin applies | ||
| * clone(obj) -> type(obj) - method to clone obj | ||
| """ | ||
| __all__ = ["_clone", "_check_clone"] | ||
|
|
||
| from skbase.base._clone_plugins import DEFAULT_CLONE_PLUGINS | ||
|
|
||
|
|
||
| # Adapted from sklearn's `_clone_parametrized()` | ||
| def _clone(estimator, *, safe=True, clone_plugins=None, base_cls=None): | ||
| """Construct a new unfitted estimator with the same parameters. | ||
| Clone does a deep copy of the model in an estimator | ||
| without actually copying attached data. It returns a new estimator | ||
| with the same parameters that has not been fitted on any data. | ||
| Parameters | ||
| ---------- | ||
| estimator : {list, tuple, set} of estimator instance or a single estimator instance | ||
| The estimator or group of estimators to be cloned. | ||
| safe : bool, default=True | ||
| If ``safe`` is False, clone will fall back to a deep copy on objects | ||
| that are not estimators. | ||
| clone_plugins : list of BaseCloner clone plugins, concrete descendant classes. | ||
| Must implement ``_check`` and ``_clone`` method, see ``BaseCloner`` interface. | ||
| If passed, will work through clone plugins in ``clone_plugins`` | ||
| before working through ``DEFAULT_CLONE_PLUGINS``. To override | ||
| a cloner in ``DEAULT_CLONE_PLUGINS``, simply ensure a cloner with | ||
| the same ``_check`` logis is present in ``clone_plugins``. | ||
| base_cls : reference to BaseObject | ||
| Reference to the BaseObject class from skbase.base._base. | ||
| Present for easy reference, fast imports, and potential extensions. | ||
| Returns | ||
| ------- | ||
| estimator : object | ||
| The deep copy of the input, an estimator if input is an estimator. | ||
| Notes | ||
| ----- | ||
| If the estimator's `random_state` parameter is an integer (or if the | ||
| estimator doesn't have a `random_state` parameter), an *exact clone* is | ||
| returned: the clone and the original estimator will give the exact same | ||
| results. Otherwise, *statistical clone* is returned: the clone might | ||
| return different results from the original estimator. More details can be | ||
| found in :ref:`randomness`. | ||
| """ | ||
| # handle cloning plugins: | ||
| # if no plugins provided by user, work through the DEFAULT_CLONE_PLUGINS | ||
| # if provided by user, work through user provided plugins first, then defaults | ||
| if clone_plugins is not None: | ||
| all_plugins = clone_plugins.copy() | ||
| all_plugins.append(DEFAULT_CLONE_PLUGINS.copy()) | ||
| else: | ||
| all_plugins = DEFAULT_CLONE_PLUGINS | ||
|
|
||
| for cloner_plugin in all_plugins: | ||
| cloner = cloner_plugin(safe=safe, clone_plugins=all_plugins, base_cls=base_cls) | ||
| # we clone with the first plugin in the list that: | ||
| # 1. claims it is applicable, via check | ||
| # 2. does not produce an Exception when cloning | ||
| if cloner.check(obj=estimator): | ||
| return cloner.clone(obj=estimator) | ||
|
|
||
| raise RuntimeError( | ||
| "Error in skbase _clone, catch-all plugin did not catch all " | ||
| "remaining cases. This is likely due to custom modification of the module." | ||
| ) | ||
|
|
||
|
|
||
| def _check_clone(original, clone): | ||
| """Check that clone is a valid clone of original. | ||
| Called from BaseObject.clone to validate the clone, if | ||
| the config flag check_clone is set to True. | ||
| Parameters | ||
| ---------- | ||
| original : object | ||
| The original object. | ||
| clone : object | ||
| The cloned object. | ||
| Raises | ||
| ------ | ||
| RuntimeError | ||
| If the clone is not a valid clone of the original. | ||
| """ | ||
| from skbase.utils.deep_equals import deep_equals | ||
|
|
||
| self_params = original.get_params(deep=False) | ||
|
|
||
| # check that all attributes are written to the clone | ||
| for attrname in self_params.keys(): | ||
| if not hasattr(clone, attrname): | ||
| raise RuntimeError( | ||
| f"error in {original}.clone, __init__ must write all arguments " | ||
| f"to self and not mutate them, but {attrname} was not found. " | ||
| f"Please check __init__ of {original}." | ||
| ) | ||
|
|
||
| clone_attrs = {attr: getattr(clone, attr) for attr in self_params.keys()} | ||
|
|
||
| # check equality of parameters post-clone and pre-clone | ||
| clone_attrs_valid, msg = deep_equals(self_params, clone_attrs, return_msg=True) | ||
| if not clone_attrs_valid: | ||
| raise RuntimeError( | ||
| f"error in {original}.clone, __init__ must write all arguments " | ||
| f"to self and not mutate them, but this is not the case. " | ||
| f"Error on equality check of arguments (x) vs parameters (y): {msg}" | ||
| ) |
Oops, something went wrong.