From 337b41b0b326391515d9a411065e3a34a36f860e Mon Sep 17 00:00:00 2001
From: Eric Wieser <wieser.eric@gmail.com>
Date: Wed, 5 Aug 2020 15:38:31 +0100
Subject: [PATCH] Ensure _group_selection_context is always reset

Context managers will resume with an exception if the with block calling them fails.
This happening is not an excuse to not clean up.
---
 pandas/core/groupby/groupby.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/pandas/core/groupby/groupby.py b/pandas/core/groupby/groupby.py
index ac45222625569..6c8a780859939 100644
--- a/pandas/core/groupby/groupby.py
+++ b/pandas/core/groupby/groupby.py
@@ -463,8 +463,10 @@ def _group_selection_context(groupby):
     Set / reset the _group_selection_context.
     """
     groupby._set_group_selection()
-    yield groupby
-    groupby._reset_group_selection()
+    try:
+        yield groupby
+    finally:
+        groupby._reset_group_selection()
 
 
 _KeysArgType = Union[