def mock_qnode(mock_device):
"""Provides a circuit for the subsequent tests of the operation queue"""
def circuit(x):
qml.RX(x, wires=[0])
qml.CNOT(wires=[0, 1])
qml.RY(0.4, wires=[0])
qml.RZ(-0.2, wires=[1])
return qml.expval(qml.PauliX(0)), qml.expval(qml.PauliZ(1))
node = QNode(circuit, mock_device)
node._construct([1.0], {})
return node
def test_print_applied(self, mock_device):
"""Test that printing applied gates works correctly"""
H = np.array([[0, 1], [1, 0]])
def circuit(x):
qml.RX(x, wires=[0])
qml.CNOT(wires=[0, 1])
qml.RY(0.4, wires=[0])
qml.RZ(-0.2, wires=[1])
return qml.expval(qml.PauliX(0)), qml.var(qml.Hermitian(H, wires=1))
expected_qnode_print = textwrap.dedent(
"""\
Operations
==========
RX({x}, wires=[0])
CNOT(wires=[0, 1])
RY(0.4, wires=[0])
RZ(-0.2, wires=[1])
Observables
===========
expval(PauliX(wires=[0]))
var(Hermitian([[0 1]
[1 0]], wires=[1]))"""
)
node = QNode(circuit, mock_device)
# test before construction
f = io.StringIO()
with contextlib.redirect_stdout(f):
node.print_applied()
out = f.getvalue().strip()
assert out == "QNode has not yet been executed."
# construct QNode
f = io.StringIO()
node._set_variables([0.1], {})
node._construct([0.1], {})
with contextlib.redirect_stdout(f):
node.print_applied()
out = f.getvalue().strip()
assert out == expected_qnode_print.format(x=0.1)