infra: Scope incremental cascade per parameter set

When an incremental class is parametrized at class level, a failure in
one parameter set (e.g. ipv4) should not cascade into another (e.g. ipv6)
since they are independent test cycles.

Assisted-by: Claude <noreply@anthropic.com>
Signed-off-by: Anat Wax <awax@redhat.com>

Author: Anatw

conftest.py

@@ -669,14 +669,22 @@ def pytest_report_teststatus(report, config):
     return None
 
 
+def _get_incremental_param_key(item: pytest.Item) -> str:
+    if match := re.search(r"\[(.+)\]$", item.name):
+        return match.group(1)
+    return ""
+
+
 @pytest.hookimpl(hookwrapper=True)
 def pytest_runtest_makereport(item, call):
     """
     incremental tests implementation
     """
     if call.excinfo is not None and "incremental" in item.keywords:
         parent = item.parent
-        parent._previousfailed = item
+        if not hasattr(parent, "_previousfailed"):
+            parent._previousfailed = {}
+        parent._previousfailed[_get_incremental_param_key(item)] = item
 
     outcome = yield
     report = outcome.get_result()
@@ -732,7 +740,7 @@ def pytest_runtest_setup(item):
     BASIC_LOGGER.info(f"\n{separator(symbol_='-', val=item.name)}")
     BASIC_LOGGER.info(f"{separator(symbol_='-', val='SETUP')}")
     if "incremental" in item.keywords:
-        previousfailed = getattr(item.parent, "_previousfailed", None)
+        previousfailed = getattr(item.parent, "_previousfailed", {}).get(_get_incremental_param_key(item))
         if previousfailed is not None:
             pytest.xfail("previous test failed (%s)" % previousfailed.name)