From 0ea18892657ec3adc61f0c3e02f7cc8c13b0f35c Mon Sep 17 00:00:00 2001
From: Daniel Hahler <git@thequod.de>
Date: Sun, 24 Mar 2019 11:17:55 +0100
Subject: [PATCH] test_as_errors: use subprocess with `-W`

Ref: https://github.com/pytest-dev/pytest/pull/4981
---
 testing/test_warnings.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/testing/test_warnings.py b/testing/test_warnings.py
index 1b4231edc..929ae8d60 100644
--- a/testing/test_warnings.py
+++ b/testing/test_warnings.py
@@ -95,10 +95,12 @@ def test_as_errors(testdir, pyfile_with_warnings, method):
         testdir.makeini(
             """
             [pytest]
-            filterwarnings= error
+            filterwarnings=error
             """
         )
-    result = testdir.runpytest(*args)
+    # Use a subprocess, since changing logging level affects other threads
+    # (xdist).
+    result = testdir.runpytest_subprocess(*args)
     result.stdout.fnmatch_lines(
         [
             "E       UserWarning: user warning",