Fix target_history date bug

qiskit_ibm_runtime/ibm_backend.py

@@ -228,7 +228,7 @@ def _get_properties(self, datetime: Optional[python_datetime] = None) -> None:
         """Gets backend properties and decodes it"""
         if datetime:
             datetime = local_to_utc(datetime)
-        if not self._properties:
+        if datetime or not self._properties:
             api_properties = self._api_client.backend_properties(self.name, datetime=datetime)
             if api_properties:
                 backend_properties = properties_from_server_data(api_properties)
@@ -241,9 +241,9 @@ def _get_defaults(self) -> None:
             if api_defaults:
                 self._defaults = defaults_from_server_data(api_defaults)
 
-    def _convert_to_target(self) -> None:
+    def _convert_to_target(self, refresh: bool = False) -> None:
         """Converts backend configuration, properties and defaults to Target object"""
-        if not self._target:
+        if refresh or not self._target:
             self._target = convert_to_target(
                 configuration=self._configuration,
                 properties=self._properties,
@@ -327,7 +327,7 @@ def target_history(self, datetime: Optional[python_datetime] = None) -> Target:
         """
         self._get_properties(datetime=datetime)
         self._get_defaults()
-        self._convert_to_target()
+        self._convert_to_target(refresh=True)
         return self._target
 
     def properties(

releasenotes/notes/target-history-date-bug-7d6dad84fc5b3d2e.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    Fixed a bug in :meth:`~qiskit_ibm_runtime.IBMBackend.target_history` where
+    the datetime parameter was not being used to retrieve backend properties from the 
+    specified date.

test/integration/test_backend.py

@@ -13,7 +13,7 @@
 """Tests for backend functions using real runtime service."""
 
 from unittest import SkipTest
-from datetime import datetime
+from datetime import datetime, timedelta
 import copy
 
 from qiskit.transpiler.target import Target
@@ -95,6 +95,14 @@ def test_backend_target(self):
             self.assertIsNotNone(backend.target)
             self.assertIsInstance(backend.target, Target)
 
+    @production_only
+    def test_backend_target_history(self):
+        """Check retrieving backend target_history."""
+        backend = self.backend
+        with self.subTest(backend=backend.name):
+            self.assertIsNotNone(backend.target_history())
+            self.assertIsNotNone(backend.target_history(datetime=datetime.now() - timedelta(30)))
+
     def test_backend_max_circuits(self):
         """Check if the max_circuits property is set."""
         backend = self.backend