Small bugfix in resilience validation (#1632)

* Fixed a bug in resilience options checking

* Linting

* linting

---------

Co-authored-by: Kevin Tian <kevin.tian@ibm.com>

qiskit_ibm_runtime/options/resilience_options.py

@@ -80,15 +80,17 @@ class ResilienceOptionsV2:
     @model_validator(mode="after")
     def _validate_options(self) -> "ResilienceOptionsV2":
         """Validate the model."""
-        if not self.measure_mitigation and any(asdict(self.measure_noise_learning).values()):
+        if not self.measure_mitigation and any(
+            value != Unset for value in asdict(self.measure_noise_learning).values()
+        ):
             raise ValueError(
                 "'measure_noise_learning' options are set, but 'measure_mitigation' is not set to True."
             )
 
-        if not self.zne_mitigation and any(asdict(self.zne).values()):
+        if not self.zne_mitigation and any(value != Unset for value in asdict(self.zne).values()):
             raise ValueError("'zne' options are set, but 'zne_mitigation' is not set to True.")
 
-        if not self.pec_mitigation and any(asdict(self.pec).values()):
+        if not self.pec_mitigation and any(value != Unset for value in asdict(self.pec).values()):
             raise ValueError("'pec' options are set, but 'pec_mitigation' is not set to True.")
 
         # Validate not ZNE+PEC

test/unit/test_estimator_options.py

@@ -87,6 +87,10 @@ class TestEstimatorOptions(IBMTestCase):
             {"resilience": {"zne": {"noise_factors": [1, 3, 5]}}},
             "'zne' options are set, but 'zne_mitigation' is not set to True",
         ),
+        (
+            {"resilience": {"pec": {"max_overhead": None, "noise_gain": 0}}},
+            "'pec' options are set, but 'pec_mitigation' is not set to True",
+        ),
     )
     def test_bad_inputs(self, val):
         """Test invalid inputs."""