Add user warning

qiskit/pulse/calibration_entries.py

@@ -13,6 +13,7 @@
 """Internal format of calibration data in target."""
 from __future__ import annotations
 import inspect
+import warnings
 from abc import ABCMeta, abstractmethod
 from collections.abc import Sequence, Callable
 from enum import IntEnum
@@ -327,9 +328,13 @@ def _build_schedule(self):
                     schedule.insert(qobj_inst.t0, qiskit_inst, inplace=True)
             self._definition = schedule
             self._parse_argument()
-        except QiskitError:
+        except QiskitError as ex:
             # When the play waveform data is missing in pulse_lib we cannot build schedule.
             # Instead of raising an error, get_schedule should return None.
+            warnings.warn(
+                f"Pulse calibration cannot be built and the entry is ignored: {ex.message}.",
+                UserWarning,
+            )
             self._definition = IncompletePulseQobj
 
     def define(

test/python/pulse/test_calibration_entries.py

@@ -326,6 +326,30 @@ def test_add_qobj(self):
         )
         self.assertEqual(schedule_to_test, schedule_ref)
 
+    def test_missing_waveform(self):
+        """Test incomplete Qobj should raise warning and calibration returns None."""
+        serialized_program = [
+            PulseQobjInstruction(
+                name="waveform_123456",
+                t0=20,
+                ch="d0",
+            ),
+        ]
+        entry = PulseQobjDef(converter=self.converter, name="my_gate")
+        entry.define(serialized_program)
+
+        with self.assertWarns(
+            UserWarning,
+            msg=(
+                "Pulse calibration cannot be built and the entry is ignored: "
+                "Instruction waveform_123456 on channel d0 is not found in Qiskit namespace. "
+                "This instruction cannot be deserialized."
+            ),
+        ):
+            out = entry.get_schedule()
+
+        self.assertIsNone(out)
+
     def test_parameterized_qobj(self):
         """Test adding and managing parameterized qobj.