abstractmethods

src/hooked_containers/common.py

@@ -1,27 +1,39 @@
-from collections.abc import Callable, MutableSequence
-from typing import Generic, TypeVar
+from abc import ABC, abstractmethod
+from collections.abc import MutableMapping, MutableSequence
+from typing import Generic, Protocol, TypeVar
 
 from . import events as e
 
 T = TypeVar("T")
 
+type MutableNesting[T] = T | MutableSequence[T] | MutableMapping[T, MutableNesting[T]]
 
-class HookedContainer(Generic[T]):
+
+class HookFunction(Protocol):
+    def __call__(self, event: e.ChangeEvent[T]) -> None: ...
+
+
+class HookedContainer(Generic[T], ABC):
     _path: MutableSequence[int]
-    hook: Callable[[e.ChangeEvent[T]], None] | None
+    hook: HookFunction
 
     def __repr__(self):
         return f"{self.__class__.__name__}({self._data!r})"
 
-    def __len__(self):
-        return len(self._data)
-
     def __iter__(self):
         return iter(self._data)
 
     def __contains__(self, value):
         return value in self._data
 
+    # MutableSequence Methods
+
+    def __len__(self):
+        return len(self._data)
+
+    @abstractmethod
+    def __getitem__(self, key): ...
+
     def __setitem__(self, s, value):
         self._data[s] = value
         if self.hook:
@@ -31,3 +43,6 @@ class HookedContainer(Generic[T]):
         del self._data[s]
         if self.hook:
             self.hook(e.RemoveItemEvent(index=s, item=self._data[s]))
+
+    @abstractmethod
+    def insert(self, index, value): ...

src/hooked_containers/events.py

@@ -7,6 +7,7 @@ T = TypeVar("T")
 @dataclass(frozen=True)
 class ChangeEvent(Generic[T]):
     index: int
+    item: T
 
 
 @dataclass(frozen=True)

src/hooked_containers/mapping.py

@@ -1,20 +1,51 @@
-from collections.abc import Callable, MutableMapping, MutableSequence, Sequence
-from typing import Generic, TypeVar
+from collections.abc import MutableMapping, MutableSequence, Sequence
+from copy import copy
+from typing import TypeVar
 
-from . import events as e
+from .common import HookedContainer, MutableNesting
+from .sequence import HookedList
 
 T = TypeVar("T")
 
 
-class HookedMapping(Generic[T], MutableMapping[T, T | MutableSequence[T], MutableMapping[T]]):
-    _data: MutableSequence[T]
-    _path: MutableSequence[int]
-    hook: Callable[[e.ChangeEvent[T]], None] | None
+class HookedMapping(HookedContainer[T], MutableMapping[T, MutableNesting[T]]):
+    _data: MutableMapping[T, MutableNesting[T]]
 
-    def __init__(self, hook, existing: MutableMapping[T], path: Sequence[int] | None = None):
+    def __init__(
+        self,
+        hook,
+        existing: MutableMapping[T, MutableNesting[T]],
+        path: Sequence[int] | None = None,
+    ):
         self.hook = hook
         self._data = existing
         self._path = list(path) if path is not None else []
 
-    def __setitem__(self, key):
-        return
+    def __getitem__(self, key: T) -> MutableNesting[T]:
+        value = self._data[key]
+        match value:
+            case MutableMapping() as mapping:
+                new_path = copy(self._path)
+                new_path.append(key)
+                return type(self)(self.hook, existing=mapping, path=new_path)
+            case MutableSequence() as seq:
+                new_path = copy(self._path)
+                new_path.append(key)
+                return HookedList(self.hook, existing=seq, path=new_path)
+            case _ as item:
+                return item
+
+    def __setitem__(self, key: T, value: MutableNesting[T]) -> None:
+        self._data[key] = value
+        if self.hook:
+            from . import events as e
+
+            self.hook(e.SetItemEvent(index=key, item=value))
+
+    def __delitem__(self, key: T) -> None:
+        item = self._data[key]
+        del self._data[key]
+        if self.hook:
+            from . import events as e
+
+            self.hook(e.RemoveItemEvent(index=key, item=item))

src/hooked_containers/sequence.py

@@ -1,19 +1,22 @@
-from collections.abc import Iterable, MutableSequence, Sequence
+from collections.abc import MutableSequence
 from copy import copy
 from typing import TypeVar
 
 from . import events as e
-from .common import HookedContainer
+from .common import HookedContainer, HookFunction
 
 T = TypeVar("T")
 
 
 class HookedList(HookedContainer[T], MutableSequence[T]):
     _data: MutableSequence[T]
+    path: MutableSequence[int]
 
-    def __init__(self, hook, existing: Iterable[T], path: Sequence[int] | None = None):
+    def __init__(self, hook: HookFunction, existing: MutableSequence[T], path: MutableSequence[int] | None = None):
         self.hook = hook
         match existing:
+            case HookedContainer(_data=seq):
+                self._data = seq
             case MutableSequence() as seq:
                 self._data = seq
             case _ as it:
@@ -27,7 +30,7 @@ class HookedList(HookedContainer[T], MutableSequence[T]):
                 new_path = copy(self._path)
                 new_path.append(s)
                 # print(new_path)
-                return HookedList(self.hook, existing=seq, path=new_path)
+                return type(self)(self.hook, existing=seq, path=new_path)
             case _ as item:
                 return item