From 5d9f74b89fd037fc1c14b909a98371b0b4eafd02 Mon Sep 17 00:00:00 2001
From: Anthony Sottile <asottile@umich.edu>
Date: Wed, 19 Oct 2022 22:07:53 -0400
Subject: [PATCH] fix test pollution of sys.modules

---
 testing/_py/test_local.py | 6 ++++++
 testing/test_pathlib.py   | 5 +++++
 2 files changed, 11 insertions(+)

diff --git a/testing/_py/test_local.py b/testing/_py/test_local.py
index 6e2c44bc2e0..995d739cec6 100644
--- a/testing/_py/test_local.py
+++ b/testing/_py/test_local.py
@@ -2,6 +2,7 @@
 import os
 import sys
 import time
+from unittest import mock
 
 import pytest
 from py import error
@@ -978,6 +979,11 @@ def test_error_preservation(self, path1):
 
 
 class TestImport:
+    @pytest.fixture(autouse=True)
+    def preserve_sys_modules(self):
+        with mock.patch.dict(sys.modules):
+            pass
+
     def test_pyimport(self, path1):
         obj = path1.join("execfile.py").pyimport()
         assert obj.x == 42
diff --git a/testing/test_pathlib.py b/testing/test_pathlib.py
index c901dc6f435..9e4e727e4ac 100644
--- a/testing/test_pathlib.py
+++ b/testing/test_pathlib.py
@@ -91,6 +91,11 @@ def path1(self, tmp_path_factory: TempPathFactory) -> Generator[Path, None, None
         yield path
         assert path.joinpath("samplefile").exists()
 
+    @pytest.fixture(autouse=True)
+    def preserve_sys_modules(self):
+        with unittest.mock.patch.dict(sys.modules):
+            yield
+
     def setuptestfs(self, path: Path) -> None:
         # print "setting up test fs for", repr(path)
         samplefile = path / "samplefile"