Update tests to avoid empty ExperimentData warning (#1349)

Update fake backend to generate fake results for each circuit and update
tests to run at least one circuit so that some results are generated.
These changes avoid generating many instances of the recently added
warning about running analysis on an empty experiment data object and
also make the tests a little more realistic.

qiskit_experiments/test/fake_backend.py

@@ -55,12 +55,25 @@ def target(self) -> Target:
         return self._target
 
     def run(self, run_input, **options):
+        if not isinstance(run_input, list):
+            run_input = [run_input]
+        results = [
+            {
+                "data": {"0": 100},
+                "shots": 100,
+                "success": True,
+                "header": {"metadata": circ.metadata},
+                "meas_level": 2,
+            }
+            for circ in run_input
+        ]
+
         result = {
             "backend_name": "fake_backend",
             "backend_version": "0",
             "qobj_id": uuid.uuid4().hex,
             "job_id": uuid.uuid4().hex,
             "success": True,
-            "results": [],
+            "results": results,
         }
         return FakeJob(backend=self, result=Result.from_dict(result))

test/calibration/test_base_calibration_experiment.py

@@ -87,6 +87,7 @@ def test_update_calibration(self):
             new_value=ref_new_value,
             param_name="to_calibrate",
             sched_name="test",
+            circuits=[QuantumCircuit(1)],
         )
         self.assertExperimentDone(exp.run(backend))
 
@@ -131,6 +132,7 @@ def test_update_calibration_update_analysis(self):
             new_value=999999,
             param_name="to_calibrate",
             sched_name="test",
+            circuits=[QuantumCircuit(1)],
         )
         exp.analysis.set_options(return_value=ref_new_value)  # Update analysis option here
         self.assertExperimentDone(exp.run(backend))
@@ -176,6 +178,7 @@ def test_update_calibration_custom_analysis(self):
             new_value=99999,
             param_name="to_calibrate",
             sched_name="test",
+            circuits=[QuantumCircuit(1)],
         )
 
         user_analysis = DoNothingAnalysis()
@@ -231,13 +234,15 @@ def test_update_calibration_batch(self):
             new_value=ref_new_value1,
             param_name="to_calibrate1",
             sched_name="test",
+            circuits=[QuantumCircuit(1)],
         )
         exp2 = MockCalExperiment(
             physical_qubits=(0,),
             calibrations=cals,
             new_value=ref_new_value2,
             param_name="to_calibrate2",
             sched_name="test",
+            circuits=[QuantumCircuit(1)],
         )
         batch_exp = BatchExperiment([exp1, exp2], flatten_results=False, backend=backend)
         self.assertExperimentDone(batch_exp.run(backend))
@@ -301,13 +306,15 @@ def test_update_calibration_parallel(self):
             new_value=ref_new_value1,
             param_name="to_calibrate1",
             sched_name="test1",
+            circuits=[QuantumCircuit(1)],
         )
         exp2 = MockCalExperiment(
             physical_qubits=(1,),
             calibrations=cals,
             new_value=ref_new_value2,
             param_name="to_calibrate2",
             sched_name="test2",
+            circuits=[QuantumCircuit(1)],
         )
         batch_exp = ParallelExperiment([exp1, exp2], flatten_results=False, backend=backend)
         self.assertExperimentDone(batch_exp.run(backend))

test/fake_experiment.py

@@ -14,6 +14,7 @@
 
 import numpy as np
 from matplotlib.figure import Figure as MatplotlibFigure
+from qiskit import QuantumCircuit
 from qiskit_experiments.framework import BaseExperiment, BaseAnalysis, Options, AnalysisResultData
 
 
@@ -61,4 +62,4 @@ def __init__(self, physical_qubits=None, backend=None, experiment_type=None):
 
     def circuits(self):
         """Fake circuits."""
-        return []
+        return [QuantumCircuit(len(self.physical_qubits))]

test/framework/test_composite.py

@@ -70,7 +70,7 @@ def test_parallel_options(self):
         self.assertEqual(par_exp.analysis.options, par_exp.analysis._default_options())
 
         with self.assertWarns(UserWarning):
-            expdata = par_exp.run(FakeBackend())
+            expdata = par_exp.run(FakeBackend(num_qubits=3))
         self.assertExperimentDone(expdata)
 
     def test_flatten_results_nested(self):
@@ -92,7 +92,7 @@ def test_flatten_results_nested(self):
             ],
             flatten_results=True,
         )
-        expdata = comp_exp.run(FakeBackend())
+        expdata = comp_exp.run(FakeBackend(num_qubits=4))
         self.assertExperimentDone(expdata)
         # Check no child data was saved
         self.assertEqual(len(expdata.child_data()), 0)
@@ -112,7 +112,7 @@ def test_flatten_results_partial(self):
             ],
             flatten_results=False,
         )
-        expdata = comp_exp.run(FakeBackend())
+        expdata = comp_exp.run(FakeBackend(num_qubits=4))
         self.assertExperimentDone(expdata)
         # Check out experiment wasn't flattened
         self.assertEqual(len(expdata.child_data()), 2)
@@ -176,7 +176,7 @@ class TestCompositeExperimentData(QiskitExperimentsTestCase):
     def setUp(self):
         super().setUp()
 
-        self.backend = FakeBackend()
+        self.backend = FakeBackend(num_qubits=4)
         self.share_level = "public"
 
         exp1 = FakeExperiment([0, 2])
@@ -302,7 +302,7 @@ def test_nested_composite(self):
         exp4 = BatchExperiment([exp3, exp1], flatten_results=False)
         exp5 = ParallelExperiment([exp4, FakeExperiment([4])], flatten_results=False)
         nested_exp = BatchExperiment([exp5, exp3], flatten_results=False)
-        expdata = nested_exp.run(FakeBackend())
+        expdata = nested_exp.run(FakeBackend(num_qubits=4))
         self.assertExperimentDone(expdata)
 
     def test_analysis_replace_results_true(self):
@@ -312,12 +312,12 @@ def test_analysis_replace_results_true(self):
         exp1 = FakeExperiment([0, 2])
         exp2 = FakeExperiment([1, 3])
         par_exp = ParallelExperiment([exp1, exp2], flatten_results=False)
-        data1 = par_exp.run(FakeBackend())
+        data1 = par_exp.run(FakeBackend(num_qubits=4))
         self.assertExperimentDone(data1)
 
         # Additional data not part of composite experiment
         exp3 = FakeExperiment([0, 1])
-        extra_data = exp3.run(FakeBackend())
+        extra_data = exp3.run(FakeBackend(num_qubits=2))
         self.assertExperimentDone(extra_data)
         data1.add_child_data(extra_data)
 
@@ -336,12 +336,12 @@ def test_analysis_replace_results_false(self):
         exp1 = FakeExperiment([0, 2])
         exp2 = FakeExperiment([1, 3])
         par_exp = BatchExperiment([exp1, exp2], flatten_results=False)
-        data1 = par_exp.run(FakeBackend())
+        data1 = par_exp.run(FakeBackend(num_qubits=4))
         self.assertExperimentDone(data1)
 
         # Additional data not part of composite experiment
         exp3 = FakeExperiment([0, 1])
-        extra_data = exp3.run(FakeBackend())
+        extra_data = exp3.run(FakeBackend(num_qubits=2))
         self.assertExperimentDone(extra_data)
         data1.add_child_data(extra_data)
 
@@ -360,7 +360,7 @@ def test_composite_tags(self):
         exp1 = FakeExperiment([0, 2])
         exp2 = FakeExperiment([1, 3])
         par_exp = BatchExperiment([exp1, exp2], flatten_results=False)
-        expdata = par_exp.run(FakeBackend())
+        expdata = par_exp.run(FakeBackend(num_qubits=4))
         self.assertExperimentDone(expdata)
         data1 = expdata.child_data(0)
         data2 = expdata.child_data(1)
@@ -390,7 +390,7 @@ def test_composite_figures(self):
         exp1.analysis.set_options(add_figures=True)
         exp2.analysis.set_options(add_figures=True)
         par_exp = BatchExperiment([exp1, exp2], flatten_results=False)
-        expdata = par_exp.run(FakeBackend())
+        expdata = par_exp.run(FakeBackend(num_qubits=4))
         self.assertExperimentDone(expdata)
         expdata.service = IBMExperimentService(local=True, local_save=False)
         expdata.auto_save = True
@@ -405,7 +405,7 @@ def test_composite_auto_save(self):
         exp1 = FakeExperiment([0, 2])
         exp2 = FakeExperiment([1, 3])
         par_exp = BatchExperiment([exp1, exp2], flatten_results=False)
-        expdata = par_exp.run(FakeBackend())
+        expdata = par_exp.run(FakeBackend(num_qubits=4))
         expdata.service = service
         self.assertExperimentDone(expdata)
         expdata.auto_save = True

test/framework/test_framework.py

@@ -38,9 +38,20 @@
 class TestFramework(QiskitExperimentsTestCase):
     """Test Base Experiment"""
 
+    def fake_job_data(self):
+        """Generate fake job data for tests"""
+        return {
+            "job_id": "123",
+            "metadata": {},
+            "shots": 100,
+            "meas_level": 2,
+            "success": True,
+            "data": {"0": 100},
+        }
+
     def test_metadata(self):
         """Test the metadata of a basic experiment."""
-        backend = FakeBackend()
+        backend = FakeBackend(num_qubits=2)
         exp = FakeExperiment((0, 2))
         expdata = exp.run(backend)
         self.assertExperimentDone(expdata)
@@ -119,7 +130,9 @@ def circuits(self):
     def test_analysis_replace_results_true(self):
         """Test running analysis with replace_results=True"""
         analysis = FakeAnalysis()
-        expdata1 = analysis.run(ExperimentData(), seed=54321)
+        expdata1 = ExperimentData()
+        expdata1.add_data(self.fake_job_data())
+        expdata1 = analysis.run(expdata1, seed=54321)
         self.assertExperimentDone(expdata1)
         result_ids = [res.result_id for res in expdata1.analysis_results()]
         expdata2 = analysis.run(expdata1, replace_results=True, seed=12345)
@@ -132,7 +145,9 @@ def test_analysis_replace_results_true(self):
     def test_analysis_replace_results_false(self):
         """Test running analysis with replace_results=False"""
         analysis = FakeAnalysis()
-        expdata1 = analysis.run(ExperimentData(), seed=54321)
+        expdata1 = ExperimentData()
+        expdata1.add_data(self.fake_job_data())
+        expdata1 = analysis.run(expdata1, seed=54321)
         self.assertExperimentDone(expdata1)
         expdata2 = analysis.run(expdata1, replace_results=False, seed=12345)
         self.assertExperimentDone(expdata2)
@@ -172,7 +187,9 @@ def test_analysis_runtime_opts(self):
         run_opts = {"opt1": True, "opt2": True, "opt3": True}
         analysis = FakeAnalysis()
         analysis.set_options(**opts)
-        analysis.run(ExperimentData(), **run_opts)
+        expdata = ExperimentData()
+        expdata.add_data(self.fake_job_data())
+        analysis.run(expdata, **run_opts)
         # add also the default 'figure_names' option
         target_opts = opts.copy()
         target_opts["figure_names"] = None
@@ -190,7 +207,9 @@ def _run_analysis(self, experiment_data, **options):
 
         analysis = FakeAnalysis()
         failed_analysis = FakeFailedAnalysis()
-        expdata1 = analysis.run(ExperimentData(), seed=54321)
+        expdata1 = ExperimentData()
+        expdata1.add_data(self.fake_job_data())
+        expdata1 = analysis.run(expdata1, seed=54321)
         self.assertExperimentDone(expdata1)
         expdata2 = failed_analysis.run(
             expdata1, replace_results=True, seed=12345
@@ -211,7 +230,9 @@ def _run_analysis(self, experiment_data, **options):
 
         analysis = FakeAnalysis()
         failed_analysis = FakeFailedAnalysis()
-        expdata1 = analysis.run(ExperimentData(), seed=54321)
+        expdata1 = ExperimentData()
+        expdata1.add_data(self.fake_job_data())
+        expdata1 = analysis.run(expdata1, seed=54321)
         self.assertExperimentDone(expdata1)
         expdata2 = failed_analysis.run(expdata1, replace_results=False, seed=12345)