From c8ccb0519ad4e7d25381703e959aafda5fb6e4c6 Mon Sep 17 00:00:00 2001
From: dangotbanned <125183946+dangotbanned@users.noreply.github.com>
Date: Fri, 13 Sep 2024 16:37:09 +0100
Subject: [PATCH] fix(typing): Satisfy `mypy` on `utils.core.update_nested`

This is due to a `TypedDict` being typed as `Mapping` instead of `MutableMapping` (like `dict`).
At runtime it is a `dict`, so I'm not making any runtime changes - this will have to do
---
 altair/utils/core.py | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/altair/utils/core.py b/altair/utils/core.py
index 7e8340324..0af95c49f 100644
--- a/altair/utils/core.py
+++ b/altair/utils/core.py
@@ -771,9 +771,21 @@ def decorate(cb: WrapsFunc[R], /) -> WrappedMethod[T, P, R] | WrappedFunc[P, R]:
     return decorate
 
 
+@overload
 def update_nested(
     original: t.MutableMapping[Any, Any],
     update: t.Mapping[Any, Any],
+    copy: Literal[False] = ...,
+) -> t.MutableMapping[Any, Any]: ...
+@overload
+def update_nested(
+    original: t.Mapping[Any, Any],
+    update: t.Mapping[Any, Any],
+    copy: Literal[True],
+) -> t.MutableMapping[Any, Any]: ...
+def update_nested(
+    original: Any,
+    update: t.Mapping[Any, Any],
     copy: bool = False,
 ) -> t.MutableMapping[Any, Any]:
     """