fix: handle when a provider is not TestProviderAPI subclass during …

…ape-test fixture setup (#2424)

src/ape/pytest/fixtures.py

@@ -119,6 +119,9 @@ def is_stateful(self, name: str) -> Optional[bool]:
         except (NotImplementedError, ProviderNotConnectedError):
             # Assume it's on since it can't be turned off.
             is_auto_mine = True
+        except AttributeError:
+            # If not a test-provider, we don't know.
+            return None
 
         if not is_auto_mine:
             # When auto-mine is disabled, it's unknown.

tests/functional/test_test.py

@@ -168,6 +168,16 @@ def test_is_stateful(self, fixture_manager, item):
         fixture_manager.add_fixture_info("bar", setup_block=1, teardown_block=2)
         assert fixture_manager.is_stateful("bar") is True
 
+    def test_is_stateful_when_not_using_test_provider(self, networks, fixture_manager, item):
+        fixture_manager._stateful_fixtures_cache = {}
+        live_provider = networks.ethereum.sepolia.get_provider("node")
+        provider = networks.active_provider
+        networks.active_provider = live_provider
+        for fixture in ("foo", "bar"):
+            actual = fixture_manager.is_stateful(fixture)
+            networks.active_provider = provider
+            assert actual is None
+
     def test_rebase(self, mocker, fixture_manager, fixture_map, create_fixture_info):
         # We must have already started our module-scope isolation.
         isolation_manager = IsolationManager(fixture_manager.config_wrapper, mocker.MagicMock())