Skip unit test with optuna version

python_tests/preferential/test_samplers.py

@@ -11,6 +11,7 @@ from optuna.distributions import IntDistribution
 from optuna.samplers import BaseSampler
 from optuna.trial import TrialState
 from optuna_dashboard.preferential import create_study
+from packaging import version
 import pytest
 
 
@@ -27,7 +28,9 @@ parametrize_sampler = pytest.mark.parametrize(
         pytest.param(
             PreferentialGPSampler,
             marks=pytest.mark.skipif(
-                sys.version_info < (3, 8), reason="BoTorch dropped Python3.7 support"
+                sys.version_info < (3, 8)
+                or version.parse(optuna.__version__) < version.parse("3.2.0"),
+                reason="BoTorch dropped Python3.7 support",
             ),
         ),
     ],

python_tests/preferential/test_study.py

@@ -8,6 +8,7 @@ from typing import Callable
 from unittest.mock import patch
 import uuid
 
+import optuna
 from optuna import copy_study
 from optuna import create_trial
 from optuna import delete_study
@@ -17,12 +18,16 @@ from optuna.exceptions import DuplicatedStudyError
 from optuna.trial import TrialState
 from optuna_dashboard.preferential import create_study
 from optuna_dashboard.preferential import load_study
+from packaging import version
 import pytest
 
 from ..storage_supplier import parametrize_storages
 from ..storage_supplier import StorageSupplier
 
 
+if version.parse(optuna.__version__) < version.parse("3.4.0"):
+    pytest.skip("Preferential optimization is introduced at v3.4.0", allow_module_level=True)
+
 if sys.version_info < (3, 8):
     pytest.skip("BoTorch dropped Python3.7 support", allow_module_level=True)