From e8feee0612246d4f3414530388c9aee6dd0f563c Mon Sep 17 00:00:00 2001
From: Ronny Pfannschmidt <opensource@ronnypfannschmidt.de>
Date: Fri, 16 Mar 2018 15:56:45 +0100
Subject: [PATCH] fix up the mark evaluator validity check

---
 _pytest/mark/evaluate.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/_pytest/mark/evaluate.py b/_pytest/mark/evaluate.py
index 1aef138b1..19eff8e00 100644
--- a/_pytest/mark/evaluate.py
+++ b/_pytest/mark/evaluate.py
@@ -27,7 +27,8 @@ class MarkEvaluator(object):
         self._mark_name = name
 
     def __bool__(self):
-        return bool(self._marks)
+        # dont cache here to prevent staleness
+        return bool(self._get_marks())
     __nonzero__ = __bool__
 
     def wasvalid(self):