Merge pull request #11564 from nicoddemus/empty-string-parametrize-11563

Fix crash using empty string for parametrized value more than once

Author: Zac-HD

changelog/11563.bugfix.rst

@@ -0,0 +1 @@
+Fixed crash when using an empty string for the same parametrized value more than once.

src/_pytest/python.py

@@ -1003,7 +1003,7 @@ def make_unique_parameterset_ids(self) -> List[str]:
  for index, id in enumerate(resolved_ids):
  if id_counts[id] > 1:
  suffix = ""
- if id[-1].isdigit():
+ if id and id[-1].isdigit():
  suffix = "_"
  new_id = f"{id}{suffix}{id_suffixes[id]}"
  while new_id in set(resolved_ids):

testing/python/metafunc.py

@@ -626,6 +626,13 @@ def getini(self, name):
  ).make_unique_parameterset_ids()
  assert result == [expected]
 
+ def test_idmaker_duplicated_empty_str(self) -> None:
+ """Regression test for empty strings parametrized more than once (#11563)."""
+ result = IdMaker(
+ ("a",), [pytest.param(""), pytest.param("")], None, None, None, None, None
+ ).make_unique_parameterset_ids()
+ assert result == ["0", "1"]
+
  def test_parametrize_ids_exception(self, pytester: Pytester) -> None:
  """
  :param pytester: the instance of Pytester class, a temporary