From 4632df37a6e00b7b1b059e8f3f5cc9b4147b20ac Mon Sep 17 00:00:00 2001
From: Alex Adamson <alex.b.adamson@gmail.com>
Date: Wed, 21 Nov 2018 14:29:08 -0500
Subject: [PATCH] Check that we can serialize the warning detail attr

---
 xdist/remote.py | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/xdist/remote.py b/xdist/remote.py
index b0092e0..1faf3b2 100644
--- a/xdist/remote.py
+++ b/xdist/remote.py
@@ -218,7 +218,15 @@ def serialize_warning_message(warning_message):
     for attr_name in warning_message._WARNING_DETAILS:
         if attr_name in ("message", "category"):
             continue
-        result[attr_name] = getattr(warning_message, attr_name)
+        attr = getattr(warning_message, attr_name)
+        # Check if we can serialize the warning detail, marking `None` otherwise
+        # Note that we need to define the attr (even as `None`) to allow deserializing
+        try:
+            dumps(attr)
+        except DumpError:
+            result[attr_name] = None
+        else:
+            result[attr_name] = attr
     return result