group error cases

src/braket/circuits/circuit_helpers.py

@@ -12,7 +12,6 @@
 # language governing permissions and limitations under the License.
 
 from braket.circuits import Circuit, ResultType
-from braket.circuits.gates import GPhase
 
 
 def validate_circuit_and_shots(circuit: Circuit, shots: int) -> None:
@@ -29,10 +28,10 @@ def validate_circuit_and_shots(circuit: Circuit, shots: int) -> None:
             if circuit has observables that cannot be simultaneously measured and `shots>0`;
             or, if `StateVector` or `Amplitude` are specified as result types when `shots>0`.
     """
-    if not circuit.instructions:
-        raise ValueError("Circuit must have instructions to run on a device")
-    if all(isinstance(inst.operator, GPhase) and not inst.control for inst in circuit.instructions):
-        raise ValueError("Circuit must have at least one non-GPhase gate to run on a device")
+    if not circuit.instructions or all(
+        not (inst.target or inst.control) for inst in circuit.instructions
+    ):
+        raise ValueError("Circuit must have at least one non-zero-qubit gate to run on a device")
     if not shots and not circuit.result_types:
         raise ValueError(
             "No result types specified for circuit and shots=0. See `braket.circuits.result_types`"

test/unit_tests/braket/circuits/test_circuit_helpers.py

@@ -18,13 +18,15 @@
 
 
 def test_validate_circuit_and_shots_no_instructions():
-    with pytest.raises(ValueError, match="Circuit must have instructions to run on a device"):
+    with pytest.raises(
+        ValueError, match="Circuit must have at least one non-zero-qubit gate to run on a device"
+    ):
         validate_circuit_and_shots(Circuit(), 100)
 
 
 def test_validate_circuit_and_shots_only_gphase():
     with pytest.raises(
-        ValueError, match="Circuit must have at least one non-GPhase gate to run on a device"
+        ValueError, match="Circuit must have at least one non-zero-qubit gate to run on a device"
     ):
         validate_circuit_and_shots(Circuit().gphase(0.15), 100)
 
@@ -34,7 +36,9 @@ def test_validate_circuit_and_shots_ctrl_gphase():
 
 
 def test_validate_circuit_and_shots_0_no_instructions():
-    with pytest.raises(ValueError, match="Circuit must have instructions to run on a device"):
+    with pytest.raises(
+        ValueError, match="Circuit must have at least one non-zero-qubit gate to run on a device"
+    ):
         validate_circuit_and_shots(Circuit(), 0)