Extend the incremental marker for parametrize

The incremental marker is adapted to handle properly test classes with parametrize defined at class level.

Fix #3125

Author: sdementen

doc/en/example/simple.rst

@@ -461,21 +461,49 @@ an ``incremental`` marker which is to be used on classes:
 
     # content of conftest.py
 
-    import pytest
+    # store history of failures per test class name and per index in parametrize (if parametrize used)
+    _test_failed_incremental: Dict[str, Dict[Tuple[int, ...], str]] = {}
 
 
     def pytest_runtest_makereport(item, call):
         if "incremental" in item.keywords:
+            # incremental marker is used
             if call.excinfo is not None:
-                parent = item.parent
-                parent._previousfailed = item
+                # the test has failed
+                # retrieve the class name of the test
+                cls_name = str(item.cls)
+                # retrieve the index of the test (if parametrize is used in combination with incremental)
+                parametrize_index = (
+                    tuple(item.callspec.indices.values())
+                    if hasattr(item, "callspec")
+                    else ()
+                )
+                # retrieve the name of the test function
+                test_name = item.originalname or item.name
+                # store in _test_failed_incremental the original name of the failed test
+                _test_failed_incremental.setdefault(cls_name, {}).setdefault(
+                    parametrize_index, test_name
+                )
 
 
     def pytest_runtest_setup(item):
         if "incremental" in item.keywords:
-            previousfailed = getattr(item.parent, "_previousfailed", None)
-            if previousfailed is not None:
-                pytest.xfail("previous test failed ({})".format(previousfailed.name))
+            # retrieve the class name of the test
+            cls_name = str(item.cls)
+            # check if a previous test has failed for this class
+            if cls_name in _test_failed_incremental:
+                # retrieve the index of the test (if parametrize is used in combination with incremental)
+                parametrize_index = (
+                    tuple(item.callspec.indices.values())
+                    if hasattr(item, "callspec")
+                    else ()
+                )
+                # retrieve the name of the first test function to fail for this class name and index
+                test_name = _test_failed_incremental[cls_name].get(parametrize_index, None)
+                # if name found, test has failed for the combination of class name & test name
+                if test_name is not None:
+                    pytest.xfail("previous test failed ({})".format(test_name))
+
 
 These two hook implementations work together to abort incremental-marked
 tests in a class.  Here is a test module example: