def test_update_mapping():
gate = SwapPermutationGate()
a, b, c = (cirq.NamedQubit(s) for s in 'abc')
mapping = {s: i for i, s in enumerate((a, b, c))}
ops = [gate(a, b), gate(b, c)]
update_mapping(mapping, ops)
assert mapping == {a: 1, b: 2, c: 0}
def test_swap_network_gate_permutation(part_lens, acquaintance_size):
n_qubits = sum(part_lens)
qubits = cirq.LineQubit.range(n_qubits)
swap_network_gate = SwapNetworkGate(part_lens, acquaintance_size)
operations = cirq.decompose_once_with_qubits(swap_network_gate, qubits)
operations = list(cirq.flatten_op_tree(operations))
mapping = {q: i for i, q in enumerate(qubits)}
update_mapping(mapping, operations)
assert mapping == {q: i for i, q in enumerate(reversed(qubits))}
def assert_permutation_decomposition_equivalence(gate: PermutationGate,
n_qubits: int) -> None:
qubits = line.LineQubit.range(n_qubits)
operations = protocols.decompose_once_with_qubits(gate, qubits)
operations = list(
cast(Sequence[ops.Operation], ops.flatten_op_tree(operations)))
mapping = {cast(ops.Qid, q): i for i, q in enumerate(qubits)}
update_mapping(mapping, operations)
expected_mapping = {qubits[j]: i for i, j in gate.permutation().items()}
assert mapping == expected_mapping, (
"{!r}.permutation({}) doesn't match decomposition.\n"
'\n'
'Actual mapping:\n'
'{}\n'
'\n'
'Expected mapping:\n'
'{}\n'.format(gate, n_qubits, [mapping[q] for q in qubits],
[expected_mapping[q] for q in qubits]))