chore(typing): type _dict (#28205)

frappe/types/frappedict.py

@@ -1,20 +1,62 @@
-class _dict(dict):
+from collections.abc import Iterable, Mapping
+from typing import (
+	TYPE_CHECKING,
+	TypeVar,
+	overload,
+)
+
+from typing_extensions import Self, override
+
+_KT = TypeVar("_KT")
+_VT = TypeVar("_VT")
+
+
+class _dict(dict[_KT, _VT]):
 	"""dict like object that exposes keys as attributes"""
 
 	__slots__ = ()
-	__getattr__ = dict.get
-	__setattr__ = dict.__setitem__
-	__delattr__ = dict.__delitem__
-	__setstate__ = dict.update
 
-	def __getstate__(self):
+	def __getattr__(self, k: str) -> _VT | None:
+		return super().get(k)  # type: ignore[arg-type]
+
+	@override
+	def __setattr__(self, k: str, v: _VT) -> None:
+		return super().__setitem__(k, v)  # type: ignore[index]
+
+	@override
+	def __delattr__(self, k: str):
+		return super().__delitem__(k)  # type: ignore[arg-type]
+
+	def __setstate__(self, m: Mapping[_KT, _VT]) -> None:
+		return super().update(m)
+
+	@override
+	def __getstate__(self) -> Self:
 		return self
 
-	def update(self, *args, **kwargs):
+	@overload  # type: ignore[override]
+	def update(self, m: Mapping[_KT, _VT], /, **kwargs: _VT) -> Self:
+		...
+
+	@overload
+	def update(self, m: Iterable[tuple[_KT, _VT]], /, **kwargs: _VT) -> Self:
+		...
+
+	@overload
+	def update(self, /, **kwargs: _VT) -> Self:
+		...
+
+	@override
+	def update(
+		self, m: Mapping[_KT, _VT] | Iterable[tuple[_KT, _VT]] | None = None, /, **kwargs: _VT
+	) -> Self:
 		"""update and return self -- the missing dict feature in python"""
-
-		super().update(*args, **kwargs)
+		if m:
+			super().update(m, **kwargs)
+		else:
+			super().update(**kwargs)
 		return self
 
-	def copy(self):
+	@override
+	def copy(self) -> "_dict[_KT, _VT]":
 		return _dict(self)