diff --git a/testing/test_recwarn.py b/testing/test_recwarn.py
index d3455946f..65989cb3c 100644
--- a/testing/test_recwarn.py
+++ b/testing/test_recwarn.py
@@ -64,12 +64,16 @@ def test_deprecated_call_ret():
     assert ret == 42
 
 def test_deprecated_call_preserves():
+    onceregistry = py.std.warnings.onceregistry.copy()
+    filters = py.std.warnings.filters[:]
     warn = py.std.warnings.warn
     warn_explicit = py.std.warnings.warn_explicit
     test_deprecated_call_raises()
     test_deprecated_call()
-    assert warn == py.std.warnings.warn
-    assert warn_explicit == py.std.warnings.warn_explicit
+    assert onceregistry == py.std.warnings.onceregistry
+    assert filters == py.std.warnings.filters
+    assert warn is py.std.warnings.warn
+    assert warn_explicit is py.std.warnings.warn_explicit
 
 def test_deprecated_explicit_call_raises():
     pytest.raises(AssertionError,