From 152ba65365ff2b45f77cf30ea298d2e54cb1fc39 Mon Sep 17 00:00:00 2001
From: Matthew Vine <32849887+MattTheCuber@users.noreply.github.com>
Date: Mon, 12 Jan 2026 15:58:48 +0000
Subject: [PATCH] feat(state): add `__contains__` dunder for `in` checks

---
 trame_server/state.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/trame_server/state.py b/trame_server/state.py
index eb82ac0..7ddf7ef 100644
--- a/trame_server/state.py
+++ b/trame_server/state.py
@@ -128,6 +128,10 @@ def __setattr__(self, key, value):
         else:
             self.__setitem__(key, value)
 
+    def __contains__(self, key):
+        key = self._translator.translate_key(key)
+        return key in self._pending_update or key in self._pushed_state
+
     def client_only(self, *_args):
         """
         Tag a given set of variable name(s) to be client only.