[fix] Fixed a bug that causes markers to be duplicated for async test functions.

Signed-off-by: Michael Seifert <[email protected]>

Author: seifertm

pytest_asyncio/plugin.py

@@ -405,7 +405,8 @@ def _from_function(cls, function: Function, /) -> Function:
             keywords=function.keywords,
             originalname=function.originalname,
         )
-        subclass_instance.own_markers.extend(function.own_markers)
+        subclass_instance.own_markers = function.own_markers
+        assert subclass_instance.own_markers == function.own_markers
         subclassed_function_signature = inspect.signature(subclass_instance.obj)
         if "event_loop" in subclassed_function_signature.parameters:
             subclass_instance.warn(
@@ -553,6 +554,7 @@ def pytest_pycollect_makeitem_convert_async_functions_to_subclass(
                 if _get_asyncio_mode(
                     node.config
                 ) == Mode.AUTO and not node.get_closest_marker("asyncio"):
+                    print("Adding asyncio marker to " + node.nodeid)
                     node.add_marker("asyncio")
                 if node.get_closest_marker("asyncio"):
                     updated_item = specialized_item_class._from_function(node)

tests/markers/test_function_scope.py

@@ -197,3 +197,34 @@ async def test_anything():
     )
     result = pytester.runpytest_subprocess("--asyncio-mode=strict")
     result.assert_outcomes(warnings=0, passed=1)
+
+
+def test_asyncio_mark_does_not_duplicate_other_marks_in_auto_mode(
+    pytester: Pytester,
+):
+    pytester.makeconftest(
+        dedent(
+            """\
+            def pytest_configure(config):
+                config.addinivalue_line(
+                    "markers", "dummy_marker: mark used for testing purposes"
+                )
+            """
+        )
+    )
+    pytester.makepyfile(
+        dedent(
+            """\
+            import pytest
+
+            @pytest.mark.dummy_marker
+            async def test_markers_not_duplicated(request):
+                markers = []
+                for node, marker in request.node.iter_markers_with_node():
+                    markers.append(marker)
+                assert len(markers) == 2
+            """
+        )
+    )
+    result = pytester.runpytest_subprocess("--asyncio-mode=auto")
+    result.assert_outcomes(warnings=0, passed=1)