Qiskit / qiskit-ibm-runtime / 29774670093

88%

main: 88%

push

github

Clear `QuantumCircuit.metadata` in wrapper sampler (#3064)

### Summary

Currently, the wrapper sampler converts circuit metadata into
passthrough data when calling `prepare`. However, said metadata is not
cleared on the`QuantumCircuit` instances that are submitted to the
`Executor`. Because of this, an example such as:
```
circuit = QuantumCircuit(backend.num_qubits)
circuit.metadata['np_type'] = np.int64(4)

for q in range(circuit.num_qubits):
    circuit.x(qubit=q)
circuit.measure_all()

pm = generate_preset_pass_manager(backend=backend, optimization_level=0)
isa_circuit = pm.run(circuit)

sampler = SamplerV2(backend)
job = sampler.run([circuit])
job.job_id()
```
will error with `TypeError: Object of type int64 is not JSON
serializable` when encoding a circuit into QPY. The proposed solution in
this PR is to make a copy of each circuit (to avoid mutating the user's
original circuits) and clear the metadata when submitting.

### Details and comments

Fixes #3063

### AI/LLM disclosure

- [x] I didn't use LLM tooling, or only used it privately.
- [ ] I used the following tool to help write this PR description:
- [ ] I used the following tool to generate or modify code:

4 of 4 new or added lines in 1 file covered. (100.0%)

8891 of 10152 relevant lines covered (87.58%)

6.95 hits per line