wrap_sub

src/hooked_containers/events.py

@@ -1,15 +1,18 @@
+from __future__ import annotations
+
 from collections.abc import MutableSequence
 from dataclasses import dataclass, field
-from typing import Generic, Protocol, TypeVar
+from typing import TYPE_CHECKING, Generic, Protocol, TypeVar
 
-from .types import MutableNesting
+if TYPE_CHECKING:
+    from .mapping import HookedMapping
 
 T = TypeVar("T")
 
 
 @dataclass(frozen=True)
 class ChangeEvent(Generic[T]):
-    root: MutableNesting[T] = field(repr=False)
+    root: HookedMapping[T] = field(repr=False)
     path: MutableSequence[int]
     item: T
 

src/hooked_containers/mapping.py

@@ -15,6 +15,7 @@ class HookedMapping(HookedContainer[T], MutableMapping[T, MutableNesting[T]]):
         self,
         existing: MutableMapping[T, MutableNesting[T]],
         hook: HookFunction | None = None,
+        root: MutableMapping[T] | None = None,
         path: MutableSequence[int] | None = None,
     ):
         match existing:
@@ -27,15 +28,19 @@ class HookedMapping(HookedContainer[T], MutableMapping[T, MutableNesting[T]]):
                 # self._data = dict(it)
         self._data = existing
         self.hook = hook
+        self._root = root if root is not None else self
         self._path = list(path) if path is not None else []
 
+    def __wrap_sub__(self, other, **kwargs):
+        return HookedMapping(other, hook=self.hook, root=self._root, **kwargs)
+
     def __getitem__(self, key: T) -> MutableNesting[T]:
         if key not in self._data:
-            return HookedMapping(self.__setitem__(key, {}), hook=self.hook, path=self.new_path(key))
+            return self.__wrap_sub__(self.__setitem__(key, {}), path=self.new_path(key))
         value = self._data[key]
         match value:
             case MutableMapping() as mapping:
-                return HookedMapping(mapping, hook=self.hook, path=self.new_path(key))
+                return self.__wrap_sub__(mapping, path=self.new_path(key))
             case _ as item:
                 return item
 
@@ -47,7 +52,11 @@ class HookedMapping(HookedContainer[T], MutableMapping[T, MutableNesting[T]]):
         suppress_hook: bool = False,
     ) -> MutableNesting[T] | None:
         new_path = self.new_path(key)
-        event = e.SetItemEvent(self, new_path, value) if key in self._data else e.AddItemEvent(self, new_path, value)
+        event = (
+            e.SetItemEvent(self._root, new_path, value)
+            if key in self._data
+            else e.AddItemEvent(self._root, new_path, value)
+        )
         match value:
             case HookedMapping(_data=value):
                 self._data[key] = value
@@ -60,4 +69,4 @@ class HookedMapping(HookedContainer[T], MutableMapping[T, MutableNesting[T]]):
     def __delitem__(self, key: T) -> None:
         item = self._data.pop(key)
         if self.hook:
-            self.hook(e.RemoveItemEvent(self, self.new_path(key), item))
+            self.hook(e.RemoveItemEvent(self._root, self.new_path(key), item))