Fixed empty id bug with old versions of pytest.

Author: Sylvain MARIE

pytest_cases/fixture_parametrize_plus.py

@@ -520,39 +520,48 @@ def get_alternative_id(self):
             return mini_idvalset(self.argnames, argval, idx=self.alternative_index)
 
 
-if PYTEST54_OR_GREATER:
-    # an empty string will be taken into account but NOT filtered out in CallSpec2.id.
-    # so instead we create a dedicated unique string and return it.
-    # Ugly but the only viable alternative seems worse: it would be to return an empty string
-    # and in `remove_empty_ids` to always remove all empty strings (not necessary the ones set by us).
-    # That is too much of a change.
+# if PYTEST54_OR_GREATER:
+#     # an empty string will be taken into account but NOT filtered out in CallSpec2.id.
+#     # so instead we create a dedicated unique string and return it.
+#     # Ugly but the only viable alternative seems worse: it would be to return an empty string
+#     # and in `remove_empty_ids` to always remove all empty strings (not necessary the ones set by us).
+#     # That is too much of a change.
 
-    EMPTY_ID = "13h#987__36a721f8Z44526!8*72"
+EMPTY_ID = "<pytest_cases_empty_id>"
 
+
+if has_pytest_param:
     def remove_empty_ids(callspec):
         # used by plugin.py to remove the EMPTY_ID from the callspecs
         callspec._idlist = [c for c in callspec._idlist if not c.startswith(EMPTY_ID)]
-
-elif PYTEST421_OR_GREATER:
-    # an empty string will be taken into account and filtered out in CallSpec2.id.
-    EMPTY_ID = ""
-
 else:
-    # an empty string will only be taken into account if its truth value is True
-    # it will be filtered out in CallSpec2.id
-    class EmptyId(str):
-        def __new__(cls):
-            return str.__new__(cls, "")
-
-        def __nonzero__(self):
-            # python 2
-            return True
+    def remove_empty_ids(callspec):
+        # used by plugin.py to remove the EMPTY_ID from the callspecs
+        callspec._idlist = [c for c in callspec._idlist if not c.endswith(EMPTY_ID)]
 
-        def __bool__(self):
-            # python 3
-            return True
 
-    EMPTY_ID = EmptyId()
+# elif PYTEST421_OR_GREATER:
+#     # an empty string will be taken into account and filtered out in CallSpec2.id.
+#     # but.... if this empty string appears several times in the tests it is appended with a number to become unique :(
+#     EMPTY_ID = ""
+#
+# else:
+#     # an empty string will only be taken into account if its truth value is True
+#     # but.... if this empty string appears several times in the tests it is appended with a number to become unique :(
+#     # it will be filtered out in CallSpec2.id
+#     class EmptyId(str):
+#         def __new__(cls):
+#             return str.__new__(cls, "")
+#
+#         def __nonzero__(self):
+#             # python 2
+#             return True
+#
+#         def __bool__(self):
+#             # python 3
+#             return True
+#
+#     EMPTY_ID = EmptyId()
 
 
 class ParamIdMakers(UnionIdMakers):

pytest_cases/plugin.py

@@ -33,9 +33,10 @@
 
 from .fixture_core1_unions import NOT_USED, is_fixture_union_params, UnionFixtureAlternative
 
-if PYTEST54_OR_GREATER:
-    # we will need to clean the empty ids explicitly in the plugin :'(
-    from .fixture_parametrize_plus import remove_empty_ids
+# if PYTEST54_OR_GREATER:
+#     # we will need to clean the empty ids explicitly in the plugin :'(
+from .fixture_parametrize_plus import remove_empty_ids
+
 
 _DEBUG = False
 
@@ -870,9 +871,9 @@ def create_call_list_from_pending_parametrizations(self):
                              for c in calls]) + "\n")
 
         # clean EMPTY_ID set by @parametrize when there is at least a MultiParamsAlternative
-        if PYTEST54_OR_GREATER:
-            for callspec in calls:
-                remove_empty_ids(callspec)
+        # if PYTEST54_OR_GREATER:
+        for callspec in calls:
+            remove_empty_ids(callspec)
 
         # save the list and put back self as the _calls facade
         self._call_list = calls

pytest_cases/tests/cases/issues/test_issue_171.py

@@ -1,5 +1,7 @@
 import pytest
-from pytest_cases import case, parametrize_with_cases
+
+from pytest_cases.common_pytest_marks import has_pytest_param
+from pytest_cases import case, parametrize_with_cases, fixture
 
 
 class CreateCases(object):
@@ -68,7 +70,7 @@ def case_create_9(self):
         return inputs, request_data
 
 
-@pytest.fixture
+@fixture
 def validationOff():
     # app.config["validation"] = False
     yield
@@ -84,12 +86,12 @@ def test_synthesis(module_results_dct):
     assert list(module_results_dct) == [
          'test_create[current_object]',
          'test_create[lala]',
-         'test_create[without_validation]',
+         'test_create[%swithout_validation]' % ("" if has_pytest_param else "1"),
          'test_create[history_object]',
          'test_create[xml_with_namespaces]',
          'test_create[duplicate_name]',
-         'test_create[duplicate_name_without_valid]',
+         'test_create[%sduplicate_name_without_valid]' % ("" if has_pytest_param else "3"),
          'test_create[not_enough_namespaceses]',
          'test_create[invalid_xml]',
-         'test_create[invalid_xml_without_valid]'
+         'test_create[%sinvalid_xml_without_valid]' % ("" if has_pytest_param else "5"),
     ]