feat: Hoist modules

anywidget/_static_asset.py

@@ -3,8 +3,6 @@
 import pathlib
 import typing
 
-import traitlets as t
-
 from anywidget._file_contents import VirtualFileContents
 
 from ._descriptor import open_comm
@@ -56,8 +54,5 @@ def __del__(self) -> None:
  """Close the comm when the asset is deleted."""
  self._comm.close()
 
- def as_traittype(self) -> t.TraitType:
- """Return a traitlet that represents the asset."""
- return t.Instance(StaticAsset, default_value=self).tag(
- sync=True, to_json=lambda *_: "anywidget-static-asset:" + self._comm.comm_id
- )
+ def serialize(self) -> str:
+ return f"anywidget-static-asset:{self._comm.comm_id}"

anywidget/widget.py

@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import typing
+from contextlib import contextmanager
 
 import ipywidgets
 import traitlets.traitlets as t
@@ -36,30 +37,29 @@ def __init__(self, *args: typing.Any, **kwargs: typing.Any) -> None:
  if in_colab():
  enable_custom_widget_manager_once()
 
- anywidget_traits = {}
+ self._anywidget_internal_state = {}
+ for key in (_ESM_KEY, _CSS_KEY):
+ if hasattr(self, key) and not self.has_trait(key):
+ self._anywidget_internal_state[key] = getattr(self, key)
+
  if not hasattr(self, _ESM_KEY):
- anywidget_traits[_ESM_KEY] = StaticAsset(_DEFAULT_ESM).as_traittype()
+ self._anywidget_internal_state[_ESM_KEY] = _DEFAULT_ESM
+
+ self._anywidget_internal_state[_ANYWIDGET_ID_KEY] = _id_for(self)
 
- # TODO: a better way to uniquely identify this subclasses?
- # We use the fully-qualified name to get an id which we
- # can use to update CSS if necessary.
- anywidget_traits[_ANYWIDGET_ID_KEY] = t.Unicode(
- f"{self.__class__.__module__}.{self.__class__.__name__}"
- ).tag(sync=True)
+ with _patch_get_state(self, self._anywidget_internal_state):
+ super().__init__(*args, **kwargs)
 
- self.add_traits(**anywidget_traits)
- super().__init__(*args, **kwargs)
  _register_anywidget_commands(self)
 
  def __init_subclass__(cls, **kwargs: dict) -> None:
  """Coerces _esm and _css to FileContents if they are files."""
  super().__init_subclass__(**kwargs)
  for key in (_ESM_KEY, _CSS_KEY) & cls.__dict__.keys():
+ # TODO: Upgrate to := when we drop Python 3.7
  value = getattr(cls, key)
- if isinstance(value, t.TraitType):
- # we don't know how to handle this
- continue
- setattr(cls, key, StaticAsset(value).as_traittype())
+ if not isinstance(value, StaticAsset):
+ setattr(cls, key, StaticAsset(value))
  _collect_anywidget_commands(cls)
 
  def _repr_mimebundle_(self, **kwargs: dict) -> tuple[dict, dict] | None:
@@ -69,3 +69,34 @@ def _repr_mimebundle_(self, **kwargs: dict) -> tuple[dict, dict] | None:
  if self._view_name is None:
  return None # type: ignore[unreachable]
  return repr_mimebundle(model_id=self.model_id, repr_text=plaintext)
+
+
+def _id_for(obj: typing.Any) -> str:
+ """Return a unique identifier for an object."""
+ # TODO: a better way to uniquely identify this subclasses?
+ # We use the fully-qualified name to get an id which we
+ # can use to update CSS if necessary.
+ return f"{obj.__class__.__module__}.{obj.__class__.__name__}"
+
+
+@contextmanager
+def _patch_get_state(
+ widget: AnyWidget, extra_state: dict[str, str | StaticAsset]
+) -> typing.Generator[None, None, None]:
+ """Patch get_state to include anywidget-specific data."""
+ original_get_state = widget.get_state
+
+ def temp_get_state():
+ return {
+ **original_get_state(),
+ **{
+ k: v.serialize() if isinstance(v, StaticAsset) else v
+ for k, v in extra_state.items()
+ },
+ }
+
+ widget.get_state = temp_get_state
+ try:
+ yield
+ finally:
+ widget.get_state = original_get_state

packages/anywidget/src/widget.js

@@ -467,6 +467,22 @@ class Runtime {
  }
 }
 
+let anywidget_static_asset = {
+ /** @param {{ model_id: string }} model */
+ serialize(model) {
+ return `anywidget-static-asset:${model.model_id}`;
+ },
+ /**
+ * @param {string} value
+ * @param {import("@jupyter-widgets/base").DOMWidgetModel["widget_manager"]} widget_manager
+ */
+ async deserialize(value, widget_manager) {
+ let model_id = value.slice("anywidget-static-asset:".length);
+ let model = await widget_manager.get_model(model_id);
+ return model;
+ },
+};
+
 // @ts-expect-error - injected by bundler
 let version = globalThis.VERSION;
 
@@ -498,6 +514,12 @@ export default function ({ DOMWidgetModel, DOMWidgetView }) {
  RUNTIMES.set(this, runtime);
  }
 
+ static serializers = {
+ ...DOMWidgetModel.serializers,
+ _esm: anywidget_static_asset,
+ _css: anywidget_static_asset,
+ };
+
  /**
  * @param {Record<string, any>} state
  *