From 92c8bbea1f276b010ea9e8519a575bb66fde4471 Mon Sep 17 00:00:00 2001
From: Adrian Sampson <adrian@radbox.org>
Date: Mon, 18 Dec 2023 17:19:36 -0500
Subject: [PATCH] DummyIO: Check for double "installs"

---
 beets/test/_common.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/beets/test/_common.py b/beets/test/_common.py
index 13fb26bb2..b0311ec46 100644
--- a/beets/test/_common.py
+++ b/beets/test/_common.py
@@ -215,6 +215,7 @@ class DummyIO:
         return self.stdin.reads
 
     def install(self):
+        assert not self.installed, "DummyIO already installed"
         self.installed = True
 
         self.orig_stdin = sys.stdin